Revert "Init"

This reverts commit aa790a20d6.

anwendung/src/components/CalenderView.jsx

@@ -23,13 +23,9 @@ export default function CalenderView(p) {
     function readEntries() {
         let url = "http://localhost:8080/entries?semesterid=" + localStorage.getItem("currentsid") +
             "&daynumber=" + currentWeekStartDay + "&yearnumber=" + currentYear + "&sessionid=" + localStorage.getItem("sessionid");
-        try {
+        fetch(url).then(r => r.json()).then(en => {
-            fetch(url).then(r => r.json()).then(en => {
+            setEntries(en)
-                setEntries(en)
+        })
-            })
-        }catch (e) {
-
-        }
     }
 
     function pushEntry(currentColumnID, row) {
@@ -123,51 +119,12 @@ export default function CalenderView(p) {
             let row = Math.floor((y_window - y_target_offset) / cellHeight) + 1;
             let currentColumnID = parseInt(e.currentTarget.id)
 
-            if (grabbedDown) {
+            if (grabbedDown)
-                if (row - 1 > selectedElement.timestart) {
-
-                    let free = true;
-                    for(let i = 0; i < entries[currentColumnID].length; i++)
-                    {
-                        if(entries[currentColumnID][i] != null && selectedElement !== entries[currentColumnID][i])
-                        {
-                            if(row <= entries[currentColumnID][i].timeend &&
-                                row >= entries[currentColumnID][i].timestart ||
-                                row > entries[currentColumnID][i].timeend &&
-                                selectedElement.timestart < entries[currentColumnID][i].timestart)
-                            {
-                                free = false;
-                                break;
-                            }
-                        }
-                    }
-
-                    if(free) {
-                        selectedElement.timeend = row + 1;
-                    }
-                }
-            } else if (row + 2 < selectedElement.timeend)
             {
-                let free = true;
+                selectedElement.timeend = row + 1;
-                for(let i = 0; i < entries[currentColumnID].length; i++)
+            }else
-                {
+            {
-                    if(entries[currentColumnID][i] != null && selectedElement !== entries[currentColumnID][i])
+                selectedElement.timestart = row;
-                    {
-                        if(row < entries[currentColumnID][i].timeend &&
-                            row >= entries[currentColumnID][i].timestart ||
-                            row < entries[currentColumnID][i].timestart &&
-                            selectedElement.timeend > entries[currentColumnID][i].timestart)
-                        {
-                            free = false;
-                            break;
-                        }
-                    }
-                }
-
-                if(free)
-                {
-                    selectedElement.timestart = row;
-                }
             }
             setUpdate(!update);
         }
@@ -179,7 +136,6 @@ export default function CalenderView(p) {
         let row = Math.floor((y_window - y_target_offset) / cellHeight) + 1;
         let currentColumnID = parseInt(e.currentTarget.id)
         let currentId = e.target.id;
-        let currentUserID = localStorage.getItem("userid");
 
         if (e.button === 0) {
             if (!currentId.includes("e")) {
@@ -188,16 +144,20 @@ export default function CalenderView(p) {
                         pushEntry(currentColumnID, row)
                     }
                 } else {
+                    grabbedDown = currentId.includes("down")
+                    /*
+                    if(currentId.includes("up"))
+                    {
+                        grabbedDown = false;
+                    }else grabbedDown = true;
+
+                     */
                     let parentID = parseInt(e.target.parentElement.id.replace("e", ""));
-                    if(currentUserID == getElementInColumn(parentID, currentColumnID).usercreatedbyid) {
+                    selectedElement = getElementInColumn(parentID, currentColumnID);
-                        grabbedDown = currentId.includes("down")
-                        selectedElement = getElementInColumn(parentID, currentColumnID);
-                    }
                 }
             }
         } else if (e.button === 2) {
-            let parentID = parseInt(e.target.id.replace("e", ""));
+            if (currentId.includes("e")) {
-            if (currentUserID == getElementInColumn(parentID, currentColumnID).usercreatedbyid && currentId.includes("e")) {
                 let id = parseInt(currentId.replace("e", ""))
                 deleteEntry(id)
             }
@@ -214,31 +174,6 @@ export default function CalenderView(p) {
         readEntries()
     }
 
-    function getEntryColor(userCreatedByID)
-    {
-        let id = localStorage.getItem("userid");
-        if(id == userCreatedByID)
-        {
-            return "#77932b";
-        }
-        else
-        {
-            return "#a2a2a2";
-        }
-    }
-
-    function getResizeBarColor(userCreatedByID)
-    {
-        let id = localStorage.getItem("userid");
-        if(id == userCreatedByID)
-        {
-            return "#5a6c20";
-        }
-        else{
-            return "#a2a2a2";
-        }
-    }
-
     useEffect(() => {
         semesterStart = 0;
         currentWeekStartDay = 0;
@@ -259,25 +194,27 @@ export default function CalenderView(p) {
         window.addEventListener("contextmenu", (e) => (e.preventDefault()))
 
         window.addEventListener("keypress", (e) => {
-            try {
+            if(e.key === "+")
-                if (e.key === "+") {
+            {
-                    cellHeight += 2
+                scrollRef.current.scrollTop = scrollRef.current.scrollTop + 100;
-                } else if (e.key === "-") {
+                cellHeight += 2
-                    if (cellHeight - 2 >= 8) {
+            }
-                        cellHeight -= 2
+            else if(e.key === "-")
-                    }
+            {
+                if(cellHeight - 2 >= 8)
+                {
+                    scrollRef.current.scrollTop = scrollRef.current.scrollTop - 100;
+                    cellHeight -= 2
                 }
-            } catch (e) {
-
             }
         })
 
 
-        setInterval(function () {
+        setInterval(function(){
-            if (selectedElement == null) {
+            if (selectedElement == null){
                 readEntries()
             }
-        }, 500);
+        }, 100);
     }, [])
 
 
@@ -315,29 +252,18 @@ export default function CalenderView(p) {
                 justifyContent: "center",
                 alignItems: "center",
                 backgroundColor: "white",
-                gap: 5,
+                gap: 5
             }}>
-                <div style={{borderRadius: 10, padding: 10, backgroundColor: "#f1f1f1"}} className={"box-shadow"}>
+
+                <div style={{ borderRadius: 10, padding: 10, backgroundColor: "#f1f1f1"}} className={"box-shadow"}>
                     <div>
                         <div className={"wochen-tag-container"}>
-                            <div
+                            <div className={"wochen-tag font-big"}>Montag {new Date(currentYear, 0, currentWeekStartDay).getDate()}.</div>
-                                className={"wochen-tag font-big"}>Montag {new Date(currentYear, 0, currentWeekStartDay).getDate()}.
+                            <div className={"wochen-tag font-big"}>Dienstag {new Date(currentYear, 0, currentWeekStartDay + 1).getDate()}.</div>
-                            </div>
+                            <div className={"wochen-tag font-big"}>Mittwoch {new Date(currentYear, 0, currentWeekStartDay + 2).getDate()}.</div>
-                            <div
+                            <div className={"wochen-tag font-big"}>Donnerstag {new Date(currentYear, 0, currentWeekStartDay + 3).getDate()}.</div>
-                                className={"wochen-tag font-big"}>Dienstag {new Date(currentYear, 0, currentWeekStartDay + 1).getDate()}.
+                            <div className={"wochen-tag font-big"}>Freitag {new Date(currentYear, 0, currentWeekStartDay + 4).getDate()}.</div>
-                            </div>
+                            <div className={"wochen-tag font-big"}>Samstag {new Date(currentYear, 0, currentWeekStartDay + 5).getDate()}.</div>
-                            <div
-                                className={"wochen-tag font-big"}>Mittwoch {new Date(currentYear, 0, currentWeekStartDay + 2).getDate()}.
-                            </div>
-                            <div
-                                className={"wochen-tag font-big"}>Donnerstag {new Date(currentYear, 0, currentWeekStartDay + 3).getDate()}.
-                            </div>
-                            <div
-                                className={"wochen-tag font-big"}>Freitag {new Date(currentYear, 0, currentWeekStartDay + 4).getDate()}.
-                            </div>
-                            <div
-                                className={"wochen-tag font-big"}>Samstag {new Date(currentYear, 0, currentWeekStartDay + 5).getDate()}.
-                            </div>
                         </div>
                     </div>
                     <div className={"calender-container"} ref={scrollRef}>
@@ -355,18 +281,14 @@ export default function CalenderView(p) {
                                     width: "100%",
                                     gridRowStart: d.timestart,
                                     gridRowEnd: d.timeend,
-                                    backgroundColor: getEntryColor(d.usercreatedbyid)
+                                    backgroundColor: "#77932b"
                                 }} id={d.id + "e"}>
-                                    <div className={"resize-grab"} id={"grabup"} style={{
+                                    <div className={"resize-grab"} id={"grabup"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                     <div style={{maxHeight: "60%"}} className={"no-pointer-events"}>
                                         <p>{internal_to_time(d.timestart) + " - " + internal_to_time(d.timeend)}</p>
                                         <p>Modul</p>
                                     </div>
-                                    <div className={"resize-grab"} id={"grabdown"} style={{
+                                    <div className={"resize-grab"} id={"grabdown"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                 </div>))}
                             </div>
 
@@ -381,19 +303,15 @@ export default function CalenderView(p) {
                                     width: "100%",
                                     gridRowStart: d.timestart,
                                     gridRowEnd: d.timeend,
-                                    backgroundColor: getEntryColor(d.usercreatedbyid)
+                                    backgroundColor: "#77932b"
                                 }} id={d.id + "e"}>
 
-                                    <div className={"resize-grab"} id={"grabup"} style={{
+                                    <div className={"resize-grab"} id={"grabup"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                     <div style={{maxHeight: "60%"}} className={"no-pointer-events"}>
                                         <p>{internal_to_time(d.timestart) + " - " + internal_to_time(d.timeend)}</p>
                                         <p>Modul</p>
                                     </div>
-                                    <div className={"resize-grab"} id={"grabdown"} style={{
+                                    <div className={"resize-grab"} id={"grabdown"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                 </div>))}
                             </div>
 
@@ -409,19 +327,15 @@ export default function CalenderView(p) {
                                     width: "100%",
                                     gridRowStart: d.timestart,
                                     gridRowEnd: d.timeend,
-                                    backgroundColor: getEntryColor(d.usercreatedbyid)
+                                    backgroundColor: "#77932b"
                                 }} id={d.id + "e"}>
 
-                                    <div className={"resize-grab"} id={"grabup"} style={{
+                                    <div className={"resize-grab"} id={"grabup"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                     <div style={{maxHeight: "60%"}} className={"no-pointer-events"}>
                                         <p>{internal_to_time(d.timestart) + " - " + internal_to_time(d.timeend)}</p>
                                         <p>Modul</p>
                                     </div>
-                                    <div className={"resize-grab"} id={"grabdown"} style={{
+                                    <div className={"resize-grab"} id={"grabdown"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                 </div>))}
                             </div>
 
@@ -436,19 +350,15 @@ export default function CalenderView(p) {
                                     width: "100%",
                                     gridRowStart: d.timestart,
                                     gridRowEnd: d.timeend,
-                                    backgroundColor: getEntryColor(d.usercreatedbyid)
+                                    backgroundColor: "#77932b"
                                 }} id={d.id + "e"}>
 
-                                    <div className={"resize-grab"} id={"grabup"} style={{
+                                    <div className={"resize-grab"} id={"grabup"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                     <div style={{maxHeight: "60%"}} className={"no-pointer-events"}>
                                         <p>{internal_to_time(d.timestart) + " - " + internal_to_time(d.timeend)}</p>
                                         <p>Moduel etc.</p>
                                     </div>
-                                    <div className={"resize-grab"} id={"grabdown"} style={{
+                                    <div className={"resize-grab"} id={"grabdown"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                 </div>))}
                             </div>
 
@@ -464,18 +374,14 @@ export default function CalenderView(p) {
                                     width: "100%",
                                     gridRowStart: d.timestart,
                                     gridRowEnd: d.timeend,
-                                    backgroundColor: getEntryColor(d.usercreatedbyid)
+                                    backgroundColor: "#77932b"
                                 }} id={d.id + "e"}>
-                                    <div className={"resize-grab"} id={"grabup"} style={{
+                                    <div className={"resize-grab"} id={"grabup"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                     <div style={{maxHeight: "60%"}} className={"no-pointer-events"}>
                                         <p>{internal_to_time(d.timestart) + " - " + internal_to_time(d.timeend)}</p>
                                         <p>Modul</p>
                                     </div>
-                                    <div className={"resize-grab"} id={"grabdown"} style={{
+                                    <div className={"resize-grab"} id={"grabdown"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                 </div>))}
                             </div>
 
@@ -491,18 +397,14 @@ export default function CalenderView(p) {
                                     width: "100%",
                                     gridRowStart: d.timestart,
                                     gridRowEnd: d.timeend,
-                                    backgroundColor: getEntryColor(d.usercreatedbyid)
+                                    backgroundColor: "#77932b"
                                 }} id={d.id + "e"}>
-                                    <div className={"resize-grab"} id={"grabup"} style={{
+                                    <div className={"resize-grab"} id={"grabup"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                     <div style={{maxHeight: "60%"}} className={"no-pointer-events"}>
                                         <p>{internal_to_time(d.timestart) + " - " + internal_to_time(d.timeend)}</p>
                                         <p>Modul</p>
                                     </div>
-                                    <div className={"resize-grab"} id={"grabdown"} style={{
+                                    <div className={"resize-grab"} id={"grabdown"}></div>
-                                        backgroundColor: getResizeBarColor(d.usercreatedbyid)
-                                    }}></div>
                                 </div>))}
                             </div>
                         </div>
@@ -518,15 +420,15 @@ export default function CalenderView(p) {
                                 justifyContent: "space-around",
                                 alignItems: "center",
                             }} className={"no-pointer-events"}>
-                                <div style={{
+                            <div style={{
-                                    borderBottom: "1px solid #363636",
+                                borderBottom: "1px solid #363636",
-                                }}><p style={{
+                            }}><p style={{
-                                    color: "gray",
+                                color: "gray",
-                                    marginTop: cellHeight - 3,
+                                marginTop: cellHeight - 3,
-                                    marginRight: 120,
+                                marginRight: 120,
-                                    fontSize: 12,
+                                fontSize: 12,
-                                    textAlign: "center"
+                                textAlign: "center"
-                                }}>{internal_to_time(i + 1)}</p></div>
+                            }}>{internal_to_time(i + 1)}</p></div>
 
                                 <div style={{
                                     borderBottom: "1px solid #363636",

anwendung/src/styles/globals.css

@@ -338,6 +338,7 @@ Calender View
     height: 6px;
     cursor: ns-resize;
     width: 100%;
+    background-color: #5a6c20;
 }
 
 

backend/.gitignore

@@ -0,0 +1,33 @@
+HELP.md
+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/

backend/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.8.7/apache-maven-3.8.7-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.1.1/maven-wrapper-3.1.1.jar

backend/mvnw

@@ -0,0 +1,316 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /usr/local/etc/mavenrc ] ; then
+    . /usr/local/etc/mavenrc
+  fi
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`\\unset -f command; \\command -v java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      jarUrl="$MVNW_REPOURL/org/apache/maven/wrapper/maven-wrapper/3.1.0/maven-wrapper-3.1.0.jar"
+    else
+      jarUrl="https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.1.0/maven-wrapper-3.1.0.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget "$jarUrl" -O "$wrapperJarPath" || rm -f "$wrapperJarPath"
+        else
+            wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath" || rm -f "$wrapperJarPath"
+        fi
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl -o "$wrapperJarPath" "$jarUrl" -f
+        else
+            curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f
+        fi
+
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  $MAVEN_DEBUG_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" \
+  "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

backend/mvnw.cmd

@@ -0,0 +1,188 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    https://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%USERPROFILE%\mavenrc_pre.bat" call "%USERPROFILE%\mavenrc_pre.bat" %*
+if exist "%USERPROFILE%\mavenrc_pre.cmd" call "%USERPROFILE%\mavenrc_pre.cmd" %*
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.1.0/maven-wrapper-3.1.0.jar"
+
+FOR /F "usebackq tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/org/apache/maven/wrapper/maven-wrapper/3.1.0/maven-wrapper-3.1.0.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% ^
+  %JVM_CONFIG_MAVEN_PROPS% ^
+  %MAVEN_OPTS% ^
+  %MAVEN_DEBUG_OPTS% ^
+  -classpath %WRAPPER_JAR% ^
+  "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" ^
+  %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%"=="" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%USERPROFILE%\mavenrc_post.bat" call "%USERPROFILE%\mavenrc_post.bat"
+if exist "%USERPROFILE%\mavenrc_post.cmd" call "%USERPROFILE%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%"=="on" pause
+
+if "%MAVEN_TERMINATE_CMD%"=="on" exit %ERROR_CODE%
+
+cmd /C exit /B %ERROR_CODE%

backend/pom.xml

@@ -0,0 +1,68 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-starter-parent</artifactId>
+        <version>3.0.6</version>
+        <relativePath/> <!-- lookup parent from repository -->
+    </parent>
+    <groupId>com.example</groupId>
+    <artifactId>backend</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>backend</name>
+    <description>backend</description>
+    <properties>
+        <java.version>17</java.version>
+    </properties>
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>com.h2database</groupId>
+            <artifactId>h2</artifactId>
+            <version>2.1.214</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-install-plugin</artifactId>
+                <version>2.5.2</version>
+                <executions>
+                    <execution>
+                        <phase>validate</phase>
+                        <goals>
+                            <goal>install-file</goal>
+                        </goals>
+                        <configuration>
+                            <groupId>com.example</groupId>
+                            <artifactId>example</artifactId>
+                            <version>1.0</version>
+                            <packaging>jar</packaging>
+                            <file>${basedir}/H2JDBCDriver/h2-2.1.214.jar</file>
+                            <generatePom>true</generatePom>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>

backend/src/main/java/com/example/backend/BackendApplication.java

@@ -0,0 +1,15 @@
+package com.example.backend;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class BackendApplication
+{
+
+    public static void main(String[] args)
+    {
+        SpringApplication.run(BackendApplication.class, args);
+    }
+
+}

backend/src/main/java/com/example/backend/anwprj/Database/DataBaseHandler.java

@@ -0,0 +1,598 @@
+package com.example.backend.anwprj.Database;
+
+import com.example.backend.discard.Encryption.RSA;
+import com.example.backend.anwprj.Entries.Entry;
+import com.example.backend.anwprj.Semesters.Semester;
+import com.example.backend.anwprj.Users.User;
+import com.example.backend.anwprj.Module.Module;
+
+import java.sql.*;
+import java.util.ArrayList;
+import java.util.List;
+
+public class DataBaseHandler
+{
+    //singleton instance of database handler
+    private static DataBaseHandler instance = null;
+
+    public static DataBaseHandler getInstance()
+    {
+        if (instance == null)
+        {
+            instance = new DataBaseHandler();
+        }
+
+        return instance;
+    }
+
+    //connection to the database
+    private Connection connection;
+    //sql statement
+    private Statement st;
+    private boolean encrypted = false;
+
+    public DataBaseHandler()
+    {
+        try
+        {
+            //connect to the local database
+            connection = DriverManager.getConnection("jdbc:h2:./database", "adm", "73bgjfdsfJ!934");
+            st = connection.createStatement();
+        } catch (SQLException e)
+        {
+            e.printStackTrace();
+        }
+    }
+
+
+    /**
+     ENTRIES
+     */
+    public void addEntry(Entry entry)
+    {
+        try
+        {
+            st.executeUpdate("insert into entries (daynumber, yearnumber, semesterid, usercreatedbyid, timestart, timeend, info) values (" +
+                    entry.getDaynumber() + ", " + entry.getYearnumber() + ", " + entry.getSemesterid() + ", " +
+                    entry.getUsercreatedbyid() + ", " + entry.getTimestart() + ", " + entry.getTimeend() + ", '" + entry.getInfo() + "')"
+                    );
+        }
+        catch(Exception e)
+        {
+            e.printStackTrace();
+        }
+    }
+
+    public Entry[][] getEntries(int semesterid, int daynumber, int yearnumber)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from entries where " +
+                    "semesterid=" + semesterid +
+                    " and yearnumber=" + yearnumber +
+                    " and daynumber between " + daynumber + " and " + daynumber + 6);
+
+            List<Entry> entryList = new ArrayList<>();
+            Entry current = null;
+            while((current = resultSetToEntry(rs)) != null)
+            {
+                entryList.add(current);
+            }
+
+            Entry[][] entries = new Entry[6][20];
+            for(int i = 0; i < 6; i++)
+            {
+                int f = 0;
+
+                for(int j = 0; j < entryList.size(); j++)
+                {
+                    if(entryList.get(j).getDaynumber() == i + daynumber)
+                    {
+                        entries[i][f] = entryList.get(j);
+                        f++;
+                    }
+                }
+            }
+
+            return entries;
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+    public void deleteEntry(int id)
+    {
+        try
+        {
+            st.executeUpdate("delete from entries where id=" + id);
+        }
+        catch (Exception e)
+        {
+
+        }
+    }
+
+    public void updateEntry(Entry entry)
+    {
+        try
+        {
+            st.executeUpdate("update entries set timeend=" + entry.getTimeend() + ", timestart=" + entry.getTimestart() + " where id=" + entry.getId());
+        }
+        catch(Exception e)
+        {
+
+        }
+    }
+
+    public Entry resultSetToEntry(ResultSet rs)
+    {
+        try
+        {
+            rs.next();
+            return new Entry(
+                    rs.getInt("id"),
+                    rs.getInt("daynumber"),
+                    rs.getInt("yearnumber"),
+                    rs.getInt("usercreatedbyid"),
+                    rs.getInt("timestart"),
+                    rs.getInt("timeend"),
+                    rs.getInt("semesterid"),
+                    rs.getString("info")
+            );
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+
+    /**
+     SEMESTER
+     */
+    //get a semester object by its name
+    public Semester getSemester(String name)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from SEMESTER where name = '" + name + "'");
+            return resultSetToSemester(rs);
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+    public Semester getSemester(int id)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from semester where id=" + id);
+            return resultSetToSemester(rs);
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+    //write a new semester to the database returns if process was successful
+    public Semester addSemester(Semester s)
+    {
+        try
+        {
+            st.executeUpdate("insert into SEMESTER (startday, endday, name, startyear, endyear) values (" + s.getStartday() + ", " + s.getEndday() + ", '" + s.getName() + "', " + s.getStartyear() + ", " + s.getEndyear() + ")");
+            return getSemester(s.getName());
+
+        } catch (Exception e)
+        {
+            return null;
+        }
+    }
+
+    public Semester[] getAllSemesters()
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from semester");
+            List<Semester> semestersList = new ArrayList<>();
+            Semester s = null;
+            while((s = resultSetToSemester(rs)) != null)
+            {
+                semestersList.add(s);
+            }
+
+            return semestersList.toArray(new Semester[0]);
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+    public Semester updateSemester(Semester semester)
+    {
+        try
+        {
+            st.executeUpdate("update semester set startday=" + semester.getStartday() + ", " +
+                    "endday=" + semester.getEndday() + ", " +
+                    "name='" + semester.getName() + "', " +
+                    "startyear=" + semester.getStartyear() + ", " +
+                    "endyear=" + semester.getEndyear() + " where id=" + semester.getId());
+
+            return getSemester(semester.getId());
+        } catch (SQLException e)
+        {
+            e.printStackTrace();
+            return null;
+        }
+    }
+
+    public void deleteSemester(int id)
+    {
+        try
+        {
+            st.executeUpdate("DELETE FROM modules WHERE semesterid=" + id);
+
+            st.executeUpdate("delete from semester where id=" + id);
+        }
+        catch(Exception e)
+        {
+
+        }
+    }
+
+    public Semester resultSetToSemester(ResultSet rs)
+    {
+        try
+        {
+            rs.next();
+            return new Semester(
+                    rs.getInt("id"),
+                    rs.getInt("startday"),
+                    rs.getInt("endday"),
+                    rs.getString("name"),
+                    rs.getInt("startyear"),
+                    rs.getInt("endyear")
+            );
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+    /**
+     MODULE
+     */
+
+    //get a module object by its id
+    public Module getModule(int id) {
+        try {
+            ResultSet rs = st.executeQuery("SELECT * FROM modules WHERE id=" + id);
+            return  resultSetToModule(rs);
+        }
+        catch (Exception ex) {
+            return null;
+        }
+    }
+
+    public Module getModule(int userid, int semesterid)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from modules where userid=" + userid + " and semesterid=" + semesterid);
+
+            return resultSetToModule(rs);
+        }
+        catch (Exception e)
+        {
+            return null;
+        }
+    }
+
+    //get module objects by its semester and its lecturer
+    public Module[] getModules(int userid) {
+        try {
+            ResultSet rs = st.executeQuery("SELECT * FROM modules WHERE userid = " + userid);
+            List<Module> moduleList = new ArrayList<>();
+            Module m = null;
+            while((m = resultSetToModule(rs)) != null)
+            {
+                moduleList.add(m);
+            }
+
+            return moduleList.toArray(new Module[0]);
+
+        }
+        catch (Exception ex){
+            return null;
+        }
+    }
+
+    public Module addModule(Module m)
+    {
+        try {
+            st.executeUpdate("insert into modules (userid, semesterid, name, activated) " +
+                    "Values (" + m.getUserid() + ", " + m.getsemesterid() + ", '" + m.getName() + "', " + m.getActivated() + ")");
+            return getModule(m.getUserid(), m.getsemesterid());
+
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+            return null;
+        }
+    }
+
+    public Module[] getAllModules() {
+        try
+        {
+            ResultSet rs = st.executeQuery("SELECT * FROM modules");
+            List<Module> moduleList = new ArrayList<>();
+            Module m = null;
+            while((m = resultSetToModule(rs)) != null)
+            {
+                moduleList.add(m);
+            }
+
+            return moduleList.toArray(new Module[0]);
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+    public Module getModuleBySemesterUserID(int userid, int semesterid)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from modules where userid=" + userid + " and semesterid=" + semesterid);
+            return resultSetToModule(rs);
+        }
+        catch(Exception e)
+        {
+            return new Module(-1, 0, 0, "", 0);
+        }
+    }
+
+    public Module updateModule(Module m)
+    {
+
+        try {
+            Module module = getModule(m.getUserid(), m.getsemesterid());
+            if(module == null)
+            {
+                addModule(m);
+            }
+            else
+            {
+                st.executeUpdate("update modules set activated=" + m.getActivated() + ", semesterid=" + m.getsemesterid() + ", name='" + m.getName() + "' where id=" + module.getid());
+            }
+
+            Module test = getModule(m.getUserid(), m.getsemesterid());
+            System.out.println(test.getActivated());
+            return test;
+        }
+        catch (SQLException ex) {
+            ex.printStackTrace();
+            return null;
+        }
+    }
+
+    public boolean deleteModule(int semesterid, int userid)
+    {
+        try {
+            st.executeUpdate("delete from modules where semesterid=" + semesterid + " and userid=" + userid);
+            return true;
+        }
+        catch(Exception ex) {
+            return false;
+        }
+    }
+
+    public Module resultSetToModule(ResultSet rs) {
+        try {
+            rs.next();
+            return new Module(
+                    rs.getInt("id"),
+                    rs.getInt("userid"),
+                    rs.getInt("semesterid"),
+                    rs.getString("name"),
+                    rs.getInt("activated"));
+        }
+        catch (Exception ex) {
+            return null;
+        }
+    }
+
+    /**
+     USER
+     */
+
+    //Alle User, die nicht admin sind
+    public User[] getAllUsers()
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from users where permission=0");
+
+            User u = null;
+
+            List<User> output = new ArrayList<>();
+
+            while((u = resultSetToUser(rs)) != null)
+            {
+                u.clearOutPassword();
+                output.add(u);
+            }
+
+            return output.toArray(new User[0]);
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+    //einen User
+    public User getUser(String mail, String password)
+    {
+
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from users where mail = '" + mail + "' and password = '" + password + "'");
+            return resultSetToUser(rs);
+        } catch (Exception e)
+        {
+            e.printStackTrace();
+        }
+
+        return null;
+    }
+
+    public User getUser(int id)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from users where id=" + id);
+            return resultSetToUser(rs);
+        } catch (Exception e)
+        {
+            return null;
+        }
+    }
+
+    public User getUser(String mail)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from users where mail='" + mail + "'");
+            User u = resultSetToUser(rs);
+            if(u != null) u.clearOutPassword();
+
+            return u;
+        } catch (SQLException e)
+        {
+            e.printStackTrace();
+            return null;
+        }
+    }
+
+    public User resultSetToUser(ResultSet rs)
+    {
+        try
+        {
+            rs.next();
+            return new User(
+                    rs.getInt("id"),
+                    rs.getString("firstname"),
+                    rs.getString("lastname"),
+                    rs.getString("mail"),
+                    rs.getString("password"),
+                    rs.getInt("permission")
+            );
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+    //add a new user object to the database returns if process was successful
+    public User addUser(User user)
+    {
+        //check if mail and passwort (key user information) is given
+        if (user.getMail() == null || user.getPassword() == null)
+        {
+            return null;
+        }
+
+        try
+        {
+            String password = user.getPassword();
+            if(encrypted)
+            {
+                RSA rsa = RSA.getInstance();
+                byte[] psw = rsa.loadByteArray(password);
+                try {
+                    password = rsa.decrypt(psw);
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
+            }
+            st.executeUpdate("insert into users (firstname, lastname, mail, password, permission) values (" + "'" + user.getFirstName() + "', '" + user.getLastName() + "', '" + user.getMail() + "', '" + password + "', " + 0 + ")");
+            return getUser(user.getMail(), user.getPassword());
+        } catch (Exception e)
+        {
+            return null;
+        }
+
+    }
+
+    public User updateUser(User user, int id, boolean elevationRequestByAdmin)
+    {
+        try
+        {
+            String password = user.getPassword();
+            if(encrypted)
+            {
+                RSA rsa = RSA.getInstance();
+                byte[] psw = rsa.loadByteArray(password);
+                try {
+                    password = rsa.decrypt(psw);
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
+            }
+
+            if(!elevationRequestByAdmin)
+            {
+                st.executeUpdate("update users set " +
+                        "firstname='" + user.getFirstName() + "', " +
+                        "lastname='" + user.getLastName() + "', " +
+                        "mail='" + user.getMail() + "', " +
+                        "password='" + password + "' " +
+                        "where id=" + id);
+            }
+            else
+            {
+                st.executeUpdate("update users set " +
+                        "firstname='" + user.getFirstName() + "', " +
+                        "lastname='" + user.getLastName() + "', " +
+                        "mail='" + user.getMail() + "', " +
+                        "password='" + password + "'," +
+                        "permission=" + user.getPermissions() +
+                        "where id=" + id);
+            }
+
+            return getUser(id);
+        } catch (SQLException e)
+        {
+            e.printStackTrace();
+            return null;
+        }
+    }
+
+    public boolean deleteUser(String mail)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("SELECT id FROM user WHERE mail='" + mail + "'");
+            rs.next();
+            int id = rs.getInt("id");
+            st.executeUpdate("DELETE FROM modules WHERE lecturerId = " + id);
+
+            st.executeUpdate("delete from users where mail='" + mail + "'");
+            return true;
+        }
+        catch(Exception e)
+        {
+            e.printStackTrace();
+            return false;
+        }
+    }
+}

backend/src/main/java/com/example/backend/anwprj/Entries/Entry.java

@@ -0,0 +1,66 @@
+package com.example.backend.anwprj.Entries;
+
+//entry data class
+public class Entry
+{
+    private int id;
+    private int daynumber;
+    private int yearnumber;
+    private int usercreatedbyid;
+    private int timestart;
+    private int timeend;
+    private int semesterid;
+    private String info;
+
+    public Entry(int id, int daynumber, int yearnumber, int usercreatedbyid, int timestart, int timeend, int semesterid, String info)
+    {
+        this.id = id;
+        this.daynumber = daynumber;
+        this.yearnumber = yearnumber;
+        this.usercreatedbyid = usercreatedbyid;
+        this.timestart = timestart;
+        this.timeend = timeend;
+        this.semesterid = semesterid;
+        this.info = info;
+    }
+
+    public int getId()
+    {
+        return id;
+    }
+
+    public int getDaynumber()
+    {
+        return daynumber;
+    }
+
+    public int getYearnumber()
+    {
+        return yearnumber;
+    }
+
+    public int getUsercreatedbyid()
+    {
+        return usercreatedbyid;
+    }
+
+    public int getTimestart()
+    {
+        return timestart;
+    }
+
+    public int getTimeend()
+    {
+        return timeend;
+    }
+
+    public int getSemesterid()
+    {
+        return semesterid;
+    }
+
+    public String getInfo()
+    {
+        return info;
+    }
+}

backend/src/main/java/com/example/backend/anwprj/Module/Module.java

@@ -0,0 +1,31 @@
+package com.example.backend.anwprj.Module;
+
+//module data class
+public class Module {
+    private int id;
+    private int userid;
+    private int semesterid;
+    private String name;
+    private int activated;
+
+
+    public Module(int id, int userid, int semesterid, String name, int activated)
+    {
+        this.id = id;
+        this.userid = userid;
+        this.semesterid = semesterid;
+        this.name = name;
+        this.activated = activated;
+    }
+
+    public int getid() { return id; }
+
+    public int getUserid() { return userid; }
+
+    public int getsemesterid() { return semesterid; }
+
+    public String getName() { return name; }
+
+    public int getActivated() { return activated; }
+
+}

backend/src/main/java/com/example/backend/anwprj/Semesters/Semester.java

@@ -0,0 +1,45 @@
+package com.example.backend.anwprj.Semesters;
+
+//semester data class
+public class Semester
+{
+    private int id;
+    private int startday;
+    private int endday;
+    private String name;
+    private int startyear;
+    private int endyear;
+
+    public Semester(int id, int startday, int endday, String name, int startyear, int endyear) {
+        this.id = id;
+        this.startday = startday;
+        this.endday = endday;
+        this.name = name;
+        this.startyear = startyear;
+        this.endyear = endyear;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public int getStartday() {
+        return startday;
+    }
+
+    public int getEndday() {
+        return endday;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public int getStartyear() {
+        return startyear;
+    }
+
+    public int getEndyear() {
+        return endyear;
+    }
+}

backend/src/main/java/com/example/backend/anwprj/Users/User.java

@@ -0,0 +1,57 @@
+package com.example.backend.anwprj.Users;
+
+//user data class
+public class User
+{
+    private int id;
+    private String firstName;
+    private String lastName;
+    private String mail;
+    private String password;
+    private int permissions;
+
+    public User(int id, String firstName, String lastName, String mail, String password, int permissions)
+    {
+        this.id = id;
+        this.firstName = firstName;
+        this.lastName = lastName;
+        this.mail = mail;
+        this.password = password;
+        this.permissions = permissions;
+    }
+
+    public int getId()
+    {
+        return id;
+    }
+
+    public String getFirstName()
+    {
+        return firstName;
+    }
+
+    public String getLastName()
+    {
+        return lastName;
+    }
+
+    public String getMail()
+    {
+        return mail;
+    }
+
+    public String getPassword()
+    {
+        return password;
+    }
+
+    public int getPermissions()
+    {
+        return permissions;
+    }
+
+    public void clearOutPassword()
+    {
+        password = "****";
+    }
+}

backend/src/main/java/com/example/backend/anwprj/Users/UserPermissions.java

@@ -0,0 +1,20 @@
+package com.example.backend.anwprj.Users;
+
+//mapping of the integer rights to enum
+public enum UserPermissions
+{
+    self(0),
+    admin(1);
+
+    private final int value;
+
+    public int getValue()
+    {
+        return value;
+    }
+
+    private UserPermissions(int value)
+    {
+        this.value = value;
+    }
+}

backend/src/main/java/com/example/backend/anwprj/Users/UserSessionIDHandler.java

@@ -0,0 +1,68 @@
+package com.example.backend.anwprj.Users;
+
+import com.example.backend.anwprj.Database.DataBaseHandler;
+
+import java.nio.charset.StandardCharsets;
+import java.util.HashMap;
+
+public class UserSessionIDHandler
+{
+    //stores mapping of session ids to users
+    public static HashMap<String, User> mapping = new HashMap<>();
+
+    //returns a user object by its session id (ONLY FOR SERVER INTERNAL USE!)
+    public static User getUserBySessionID(String sessionID)
+    {
+        return mapping.get(sessionID);
+    }
+
+    public static boolean removeUser(String sessionID)
+    {
+        try
+        {
+            mapping.remove(sessionID);
+            return true;
+        }
+        catch(Exception e)
+        {
+            return false;
+        }
+    }
+
+    public static String addUser(String mail, String password)
+    {
+        //try to get user from database
+        User user = DataBaseHandler.getInstance().getUser(mail, password);
+
+        //if user exists
+        if(user != null)
+        {
+            //generate random session id based on ascii table
+            byte[] id = new byte[100];
+
+            for(int i = 0; i < id.length; i++)
+            {
+                id[i] = (byte) (Math.random() * 26 + 64);
+            }
+
+            String generatedString = new String(id, StandardCharsets.US_ASCII);
+
+            mapping.put(generatedString, user);
+
+            //makes user session expire after ca. 2h
+            new java.util.Timer().schedule(new java.util.TimerTask(){
+
+                @Override
+                public void run()
+                {
+                    mapping.remove(generatedString);
+                    return;
+                }
+            }, 7500000);
+
+            return generatedString;
+        }
+
+        return "failed";
+    }
+}

backend/src/main/java/com/example/backend/anwprj/controller/EntriesController.java

@@ -0,0 +1,102 @@
+package com.example.backend.anwprj.controller;
+
+import com.example.backend.anwprj.Database.DataBaseHandler;
+import com.example.backend.anwprj.Entries.Entry;
+import com.example.backend.anwprj.Users.User;
+import com.example.backend.anwprj.Users.UserSessionIDHandler;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+@RestController
+public class EntriesController
+{
+    private DataBaseHandler db;
+
+    {
+        db = DataBaseHandler.getInstance();
+    }
+
+    /**
+     GET
+     a set of entries for a week, based on the semester, the startdaynumber of the week and the year
+     Every user is allowed
+     */
+    @CrossOrigin
+    @GetMapping("/entries")
+    public ResponseEntity<Entry[][]> getEntries(@RequestParam(name = "semesterid") int semesterid,
+                                                @RequestParam(name = "daynumber") int daynumber,
+                                                @RequestParam(name = "yearnumber") int yearnumber,
+                                                @RequestParam(name = "sessionid") String sessionid)
+    {
+        User sessionUser = UserSessionIDHandler.getUserBySessionID(sessionid);
+
+        if (sessionUser != null)
+        {
+            return new ResponseEntity<>(db.getEntries(semesterid, daynumber, yearnumber), HttpStatus.OK);
+        }
+
+        return new ResponseEntity<>(null, HttpStatus.FORBIDDEN);
+    }
+
+    /**
+     POST
+     A new entry to the database. Every user except of admins is allowed
+     */
+
+    @CrossOrigin
+    @PostMapping("/entries")
+    public ResponseEntity<Boolean> postEntry(@RequestBody Entry entry, @RequestParam(name = "sessionid") String sessionid)
+    {
+        User sessionUser = UserSessionIDHandler.getUserBySessionID(sessionid);
+
+        if (sessionUser != null)
+        {
+            db.addEntry(entry);
+            return new ResponseEntity<>(true, HttpStatus.OK);
+        }
+
+        return new ResponseEntity<>(false, HttpStatus.FORBIDDEN);
+    }
+
+
+    /**
+     PUT
+     Update the endTime of an existing entry in the database. Every user except of admins is allowed
+     */
+
+    @CrossOrigin
+    @PutMapping("/entries")
+    public ResponseEntity<Boolean> updateEntry(@RequestParam(name="sessionid") String sessionid, @RequestBody Entry entry)
+    {
+        User sessionUser = UserSessionIDHandler.getUserBySessionID(sessionid);
+        if (sessionUser != null)
+        {
+            db.updateEntry(entry);
+            return new ResponseEntity<>(true, HttpStatus.OK);
+        }
+
+        return new ResponseEntity<>(false, HttpStatus.FORBIDDEN);
+    }
+
+
+    /**
+     Delete
+     an existing entry from the database
+     */
+    @CrossOrigin
+    @DeleteMapping("/entries")
+    public ResponseEntity<Boolean> deleteEntry(@RequestParam(name = "id") int id, @RequestParam(name = "sessionid") String sessionid)
+    {
+        User sessionUser = UserSessionIDHandler.getUserBySessionID(sessionid);
+
+        if (sessionUser != null)
+        {
+            db.deleteEntry(id);
+            return new ResponseEntity<>(true, HttpStatus.OK);
+        }
+
+        return new ResponseEntity<>(false, HttpStatus.FORBIDDEN);
+    }
+
+}

backend/src/main/java/com/example/backend/anwprj/controller/ModuleController.java

@@ -0,0 +1,175 @@
+package com.example.backend.anwprj.controller;
+
+import com.example.backend.anwprj.Database.DataBaseHandler;
+import com.example.backend.anwprj.Module.Module;
+import com.example.backend.anwprj.Users.User;
+import com.example.backend.anwprj.Users.UserPermissions;
+import com.example.backend.anwprj.Users.UserSessionIDHandler;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Ein Modul hier entspricht nicht z.b. Analysis im Allgemeinen.
+ * Es beschreibt die Verbindung zwischen einem Dozenten und Analysis in einem Speziellen Semester.
+ */
+
+@RestController
+public class ModuleController
+{
+    private final DataBaseHandler db;
+
+    {
+        db = DataBaseHandler.getInstance();
+    }
+
+
+    /**
+    GET
+     A Module by its id
+     */
+    @CrossOrigin
+    @GetMapping("/module/id")
+    public ResponseEntity<Module[]> getModules(
+            @RequestParam(name = "sessionid") String sessionID)
+    {
+
+        User user = UserSessionIDHandler.getUserBySessionID(sessionID);
+
+        if (user != null)
+        {
+            Module[] modules = db.getModules(user.getId());
+            if (modules != null)
+            {
+                return new ResponseEntity<>(modules, HttpStatus.OK);
+            }
+
+            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
+        }
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+    /**
+     GET
+    Get A Module by the matching semester and user id (important for edit function in frontend)
+     */
+    @CrossOrigin
+    @GetMapping("/module/suid")
+    public ResponseEntity<Module[]> getModulesBySemesterUserID(@RequestParam(name = "sessionid") String sessionid, @RequestParam(name = "userid") String userid, @RequestParam(name = "semesterid") int semesterid)
+    {
+        User user = UserSessionIDHandler.getUserBySessionID(sessionid);
+        String[] userIDSSplit = userid.split("a");
+        int[] userIDS = new int[userIDSSplit.length];
+        for(int i = 0; i < userIDS.length; i++)
+        {
+            userIDS[i] = Integer.parseInt(userIDSSplit[i]);
+        }
+
+        if(user != null && user.getPermissions() == UserPermissions.admin.getValue())
+        {
+            List<Module> result = new ArrayList<>();
+
+            for(int i = 0; i < userIDS.length; i++)
+            {
+                result.add(db.getModuleBySemesterUserID(userIDS[i], semesterid));
+            }
+
+            return new ResponseEntity<>(result.toArray(new Module[0]), HttpStatus.OK);
+        }
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+    /**
+     GET
+     all modules from the database. (Not used now)
+     */
+    @CrossOrigin
+    @GetMapping("/module/all")
+    public ResponseEntity<Module[]> getModule(@RequestParam(name = "sessionid") String sessionid)
+    {
+        User u = UserSessionIDHandler.getUserBySessionID(sessionid);
+
+        if (u != null)
+        {
+            if (u.getPermissions() == UserPermissions.admin.getValue())
+            {
+                return new ResponseEntity<>(db.getAllModules(), HttpStatus.OK);
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     POST
+     a new module entry. (When a user is selected in a semester.)
+     */
+    @CrossOrigin
+    @PostMapping("/module")
+    public ResponseEntity<Module> addModule(@RequestBody Module module, @RequestParam(name = "sessionid") String sessionID)
+    {
+
+        System.out.println("test1");
+        User user = UserSessionIDHandler.getUserBySessionID(sessionID);
+
+        if (user.getPermissions() == UserPermissions.admin.getValue())
+        {
+            Module m = db.addModule(module);
+            if (m != null)
+            {
+                return new ResponseEntity<>(m, HttpStatus.OK);
+            }
+
+            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
+        }
+
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+    /**
+    PUT
+     Update a Module
+     */
+    @CrossOrigin
+    @PutMapping("/module")
+    public ResponseEntity<Module> updateModule(@RequestBody Module module, @RequestParam(name = "sessionid") String sessionID)
+    {
+
+        User u = UserSessionIDHandler.getUserBySessionID(sessionID);
+        if (u != null && u.getPermissions() == UserPermissions.admin.getValue())
+        {
+            Module m = db.updateModule(module);
+
+            if (m != null)
+            {
+                return new ResponseEntity<>(m, HttpStatus.OK);
+            }
+
+            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
+        }
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+    /**
+    DELETE
+    Delete A Module
+     */
+    @CrossOrigin
+    @DeleteMapping("/module")
+    public void deleteModule(@RequestParam(name = "sessionid") String sessionid, @RequestParam(name = "semesterid") int semesterid, @RequestParam(name = "userid") int userid)
+    {
+        User u = UserSessionIDHandler.getUserBySessionID(sessionid);
+        if (u != null && u.getPermissions() == UserPermissions.admin.getValue())
+        {
+            db.deleteModule(semesterid, userid);
+        }
+
+    }
+}

backend/src/main/java/com/example/backend/anwprj/controller/SemesterController.java

@@ -0,0 +1,136 @@
+package com.example.backend.anwprj.controller;
+
+import com.example.backend.anwprj.Database.DataBaseHandler;
+import com.example.backend.anwprj.Semesters.Semester;
+import com.example.backend.anwprj.Users.User;
+import com.example.backend.anwprj.Users.UserPermissions;
+import com.example.backend.anwprj.Users.UserSessionIDHandler;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+@RestController
+public class SemesterController
+{
+    //reference to the database handler
+    private DataBaseHandler db;
+
+    {
+        db = DataBaseHandler.getInstance();
+    }
+
+    //get a semester object by its name
+    @CrossOrigin
+    @GetMapping("/semester")
+    public ResponseEntity<Semester> getSemester(@RequestParam(name="name") String name, @RequestParam(name="sessionid") String sessionID)
+    {
+        User u = UserSessionIDHandler.getUserBySessionID(sessionID);
+
+        if(u != null)
+        {
+            Semester s = db.getSemester(name);
+            if (s != null)
+            {
+                return new ResponseEntity<>(s, HttpStatus.OK);
+            }
+
+            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
+        }
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+    @CrossOrigin
+    @GetMapping("/semester/id")
+    public ResponseEntity<Semester> getSemester(@RequestParam(name="id") int id, @RequestParam(name="sessionid") String sessionID)
+    {
+        User u = UserSessionIDHandler.getUserBySessionID(sessionID);
+
+        if(u != null)
+        {
+            Semester s = db.getSemester(id);
+            if(s != null)
+            {
+                return new ResponseEntity<>(s, HttpStatus.OK);
+            }
+
+            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
+        }
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+    @CrossOrigin
+    @GetMapping("/semester/all")
+    public ResponseEntity<Semester[]> getSemester(@RequestParam(name="sessionid") String sessionid)
+    {
+        User u = UserSessionIDHandler.getUserBySessionID(sessionid);
+
+        if(u != null)
+        {
+            if(u.getPermissions() == UserPermissions.admin.getValue())
+            {
+                return new ResponseEntity<>(db.getAllSemesters(), HttpStatus.OK);
+            }
+        }
+
+        return null;
+    }
+
+
+    //a new semester add is requested (only allowed for admin users)
+    @CrossOrigin
+    @PostMapping("/semester")
+    public ResponseEntity<Semester> addSemester(@RequestBody Semester semester, @RequestParam(name="sessionid") String sessionID)
+    {
+        User user = UserSessionIDHandler.getUserBySessionID(sessionID);
+
+        if(user.getPermissions() == UserPermissions.admin.getValue())
+        {
+            Semester s = db.addSemester(semester);
+            if(s != null)
+            {
+
+                return new ResponseEntity<>(s, HttpStatus.OK);
+            }
+
+            return new ResponseEntity<>(null, HttpStatus.NOT_FOUND);
+        }
+
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+
+    @CrossOrigin
+    @PutMapping("/semester")
+    public ResponseEntity<Semester> updateSemester(@RequestBody Semester semester, @RequestParam(name="sessionid") String sessionID)
+    {
+        User u = UserSessionIDHandler.getUserBySessionID(sessionID);
+        if(u != null && u.getPermissions() == UserPermissions.admin.getValue())
+        {
+            Semester s = db.updateSemester(semester);
+
+            if(s != null)
+            {
+                return new ResponseEntity<>(s, HttpStatus.OK);
+            }
+
+            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
+        }
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+    @CrossOrigin
+    @DeleteMapping("/semester")
+    public void deleteSemester(@RequestParam(name="sessionid") String sessionid, @RequestParam(name="id") int id)
+    {
+        User u = UserSessionIDHandler.getUserBySessionID(sessionid);
+        if(u != null && u.getPermissions() == UserPermissions.admin.getValue())
+        {
+            db.deleteSemester(id);
+        }
+
+    }
+}

backend/src/main/java/com/example/backend/anwprj/controller/UserController.java

@@ -0,0 +1,184 @@
+package com.example.backend.anwprj.controller;
+
+import com.example.backend.discard.Encryption.RSA;
+import com.example.backend.anwprj.Database.DataBaseHandler;
+import com.example.backend.anwprj.Users.User;
+import com.example.backend.anwprj.Users.UserPermissions;
+import com.example.backend.anwprj.Users.UserSessionIDHandler;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+@RestController
+public class UserController {
+    //reference to the database handler
+    private DataBaseHandler db;
+
+    {
+        db = DataBaseHandler.getInstance();
+    }
+
+    @CrossOrigin
+    @GetMapping("/users/all")
+    public ResponseEntity<User[]> getAllUsers(@RequestParam(name = "sessionid") String sessionid)
+    {
+        User u = UserSessionIDHandler.getUserBySessionID(sessionid);
+
+        if(u != null && u.getPermissions() == UserPermissions.admin.getValue())
+        {
+            User[] output = db.getAllUsers();
+            return new ResponseEntity<>(output, HttpStatus.OK);
+        }
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+
+    //a user wants to login
+    @CrossOrigin
+    @GetMapping("/users")
+    public ResponseEntity<String> login(@RequestParam(name = "mail") String mail, @RequestParam(name = "password") String password) {
+        //generate a session id for the user trying to login
+        boolean isEncrypted = false;
+        if(isEncrypted)
+        {
+            RSA rsa = RSA.getInstance();
+            byte[] psw = rsa.loadByteArray(password);
+            try {
+                password = rsa.decrypt(psw);
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+
+        String sessionID = UserSessionIDHandler.addUser(mail, password);
+
+        return new ResponseEntity<>(sessionID, HttpStatus.OK);
+    }
+
+    @CrossOrigin
+    @GetMapping("/users/logout")
+    public ResponseEntity<Boolean> logout(@RequestParam(name = "sessionid") String sessionID) {
+        boolean success = UserSessionIDHandler.removeUser(sessionID);
+        return new ResponseEntity<>(success, HttpStatus.OK);
+    }
+
+    @CrossOrigin
+    @GetMapping("/users/data")
+    public ResponseEntity<User> getUserData(
+            @RequestParam(name = "sessionid") String sessionID,
+            @RequestParam(name = "mail") String mail) {
+        User sessionUser = UserSessionIDHandler.getUserBySessionID(sessionID);
+
+        if (sessionUser != null) {
+            System.out.println(sessionUser.getMail() + " " + mail);
+
+            if (sessionUser.getMail().equals(mail) || sessionUser.getPermissions() == UserPermissions.admin.getValue()) {
+                User searchedUser = db.getUser(mail);
+                return new ResponseEntity<>(searchedUser, HttpStatus.OK);
+            }
+        }
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+    @CrossOrigin
+    @GetMapping("/users/check")
+    public ResponseEntity<User> checkLogin(@RequestParam(name="sessionid") String sessionid)
+    {
+        User u = UserSessionIDHandler.getUserBySessionID(sessionid);
+
+        if(u != null)
+        {
+            return new ResponseEntity<>(db.getUser(u.getId()), HttpStatus.OK);
+        }
+
+        return new ResponseEntity<>(HttpStatus.NOT_FOUND);
+    }
+
+    //adds a new user to the database (cannot create an admin user)
+    @CrossOrigin
+    @PostMapping("/users")
+    public ResponseEntity<String> addUser(@RequestBody User user) {
+        User checkUser = db.getUser(user.getMail());
+
+        if (checkUser != null) {
+            return new ResponseEntity<>("mail", HttpStatus.FORBIDDEN);
+        }
+
+        //if user was successfully added to database
+        User u = db.addUser(user);
+
+        if (u != null) {
+            //generate a session id
+            return new ResponseEntity<String>(UserSessionIDHandler.addUser(user.getMail(), user.getPassword()), HttpStatus.OK);
+        }
+
+        return new ResponseEntity<String>(HttpStatus.BAD_REQUEST);
+    }
+
+    @CrossOrigin
+    @PutMapping("/users")
+    public ResponseEntity<Boolean> updateUser(@RequestParam(name = "sessionid") String sessionID, @RequestBody User u, @RequestParam(name = "mail") String mail) {
+        User sessionUser = UserSessionIDHandler.getUserBySessionID(sessionID);
+
+        if (sessionUser != null) {
+            if (sessionUser.getMail().equals(mail) || sessionUser.getPermissions() == UserPermissions.admin.getValue()) {
+                System.out.println(sessionUser.getId());
+
+                User resultingUser = db.updateUser(u, sessionUser.getId(), false);
+
+                if (resultingUser != null) {
+                    UserSessionIDHandler.removeUser(sessionID);
+                    return new ResponseEntity<>(true, HttpStatus.OK);
+                }
+
+                return new ResponseEntity<>(false, HttpStatus.NOT_FOUND);
+            }
+        }
+
+        return new ResponseEntity<>(false, HttpStatus.FORBIDDEN);
+    }
+
+    @CrossOrigin
+    @PutMapping("/users/elevate")
+    public ResponseEntity<Boolean> elevateUser(
+            @RequestParam(name = "sessionid") String sessionID,
+            @RequestParam(name = "mail") String mail,
+            @RequestParam(name = "permission") int permission)
+    {
+        User sessionUser = UserSessionIDHandler.getUserBySessionID(sessionID);
+
+        if(sessionUser != null && sessionUser.getPermissions() == UserPermissions.admin.getValue())
+        {
+            System.out.println("test");
+            User userToUpdateTemplate = db.getUser(mail);
+            User userToUpdate = new User(userToUpdateTemplate.getId(), userToUpdateTemplate.getFirstName(), userToUpdateTemplate.getLastName(),
+                    userToUpdateTemplate.getMail(), userToUpdateTemplate.getPassword(), permission);
+
+            User resultingUser = db.updateUser(userToUpdate, userToUpdate.getId(), true);
+
+            if(resultingUser == null)
+            {
+                return new ResponseEntity<>(false, HttpStatus.NOT_FOUND);
+            }
+
+            return new ResponseEntity<>(true, HttpStatus.OK);
+        }
+
+        return new ResponseEntity<>(false, HttpStatus.FORBIDDEN);
+    }
+
+    @CrossOrigin
+    @DeleteMapping("/users")
+    public ResponseEntity<Boolean> deleteUser(@RequestParam(name = "sessionid") String sessionID, @RequestParam(name = "mail") String mail) {
+        User sessionUser = UserSessionIDHandler.getUserBySessionID(sessionID);
+
+        if (sessionUser != null && sessionUser.getPermissions() == UserPermissions.admin.getValue()) {
+            return new ResponseEntity<>(db.deleteUser(mail), HttpStatus.OK);
+        }
+
+        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+    }
+
+}

backend/src/main/java/com/example/backend/discard/DayController.java

@@ -0,0 +1,60 @@
+package com.example.backend.discard;
+
+import com.example.backend.anwprj.Database.DataBaseHandler;
+import com.example.backend.discard.Days.Day;
+import com.example.backend.anwprj.Users.User;
+import com.example.backend.anwprj.Users.UserPermissions;
+import com.example.backend.anwprj.Users.UserSessionIDHandler;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+@RestController
+public class DayController
+{
+
+//    private DataBaseHandler db;
+//
+//    {
+//        db = DataBaseHandler.getInstance();
+//    }
+//
+//    @CrossOrigin
+//    @GetMapping("/days")
+//    public ResponseEntity<Day> getDay(
+//            @RequestParam(name="sessionid") String sessionID,
+//            @RequestParam(name="dayinyear") int dayinyear,
+//            @RequestParam(name="yearnumber") int yearnumber,
+//            @RequestParam(name="semesterid") int semesterID)
+//    {
+//        User u = UserSessionIDHandler.getUserBySessionID(sessionID);
+//
+//        if(u != null)
+//        {
+//            Day d = db.getDay(dayinyear, yearnumber, semesterID);
+//
+//            if (d != null)
+//            {
+//                return new ResponseEntity<>(d, HttpStatus.OK);
+//            }
+//
+//            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
+//        }
+//
+//        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+//    }
+//
+//    @CrossOrigin
+//    @PostMapping("/days")
+//    public ResponseEntity<Day> addDay(@RequestBody Day day, @RequestParam(name="sessionid") String sessionID)
+//    {
+//        User u = UserSessionIDHandler.getUserBySessionID(sessionID);
+//
+//        if(u != null && u.getPermissions() == UserPermissions.admin.getValue())
+//        {
+//            return new ResponseEntity<>(db.addDay(day), HttpStatus.OK);
+//        }
+//
+//        return new ResponseEntity<>(null, HttpStatus.FORBIDDEN);
+//    }
+}

backend/src/main/java/com/example/backend/discard/Days/Day.java

@@ -0,0 +1,32 @@
+package com.example.backend.discard.Days;
+
+public class Day
+{
+    private int id;
+    private int dayinyear;
+    private int yearnumber;
+    private int semesterid;
+
+    public Day(int id, int dayinyear, int yearnumber, int semesterid) {
+        this.id = id;
+        this.dayinyear = dayinyear;
+        this.yearnumber = yearnumber;
+        this.semesterid = semesterid;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public int getDayinyear() {
+        return dayinyear;
+    }
+
+    public int getYearnumber() {
+        return yearnumber;
+    }
+
+    public int getSemesterid() {
+        return semesterid;
+    }
+}

backend/src/main/java/com/example/backend/discard/Encryption/RSA.java

@@ -0,0 +1,58 @@
+package com.example.backend.discard.Encryption;
+
+import javax.crypto.Cipher;
+import java.io.*;
+import java.nio.charset.StandardCharsets;
+import java.security.*;
+
+public class RSA {
+
+    private PublicKey publicKey;
+    private PrivateKey privateKey;
+
+    private static RSA instance = null;
+
+    public static RSA getInstance()
+    {
+        if(instance == null)
+        {
+            instance = new RSA();
+        }
+
+        return instance;
+    }
+
+    private RSA(){}
+
+    public String decrypt(byte[] text) throws Exception
+    {
+        readKeyPairs();
+        var cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
+        cipher.init(Cipher.DECRYPT_MODE, privateKey);
+        var plainText = cipher.doFinal(text);
+        return new String(plainText, StandardCharsets.US_ASCII);
+    }
+
+    private void readKeyPairs() throws Exception
+    {
+        var publicInput = new ObjectInputStream(new FileInputStream(new File("./public.kfs")));
+        publicKey = (PublicKey) publicInput.readObject();
+        publicInput.close();
+
+        var privateInput = new ObjectInputStream(new FileInputStream(new File("./private.kfs")));
+        privateKey  = (PrivateKey) privateInput.readObject();
+        privateInput.close();
+    }
+
+    public byte[] loadByteArray(String text)
+    {
+        String[] split = text.split(",");
+        byte[] output = new byte[split.length];
+        for(int i = 0; i < split.length; i++)
+        {
+            output[i] = Byte.parseByte(split[i]);
+        }
+
+        return output;
+    }
+}

backend/src/main/java/com/example/backend/discard/OldDataBaseFunctions.txt

@@ -0,0 +1,124 @@
+    /**
+     * WEEKS
+     */
+
+    public Week addWeek(Week week)
+    {
+        try
+        {
+            st.executeUpdate("insert into weeks (semesterid, weeknumber) values (" + week.getSemesterid() + ", " + week.getWeeknumber() + ")");
+
+            return getWeek(week.getSemesterid(), week.getWeeknumber());
+
+        } catch (SQLException e)
+        {
+            return null;
+        }
+    }
+
+    public Week getWeek(int id)
+    {
+        ResultSet rs = null;
+        try
+        {
+            rs = st.executeQuery("select * from weeks where id=" + id);
+
+            return resultSetToWeek(rs);
+
+        } catch (SQLException e)
+
+        {
+            return null;
+        }
+
+    }
+
+    public Week getWeek(int semesterid, int weeknumber)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from weeks where semesterid =" + semesterid + " and weeknumber=" + weeknumber);
+
+            return resultSetToWeek(rs);
+        }
+        catch (SQLException e)
+        {
+            return null;
+        }
+
+    }
+
+    private Week resultSetToWeek(ResultSet rs) {
+        try {
+            rs.next();
+
+            return new Week(
+                    rs.getInt("id"),
+                    rs.getInt("semesterid"),
+                    rs.getInt("weeknumber")
+            );
+        } catch (SQLException e) {
+            return null;
+        }
+    }
+
+    /**
+     DAYS
+     */
+    public Day addDay(Day day)
+    {
+        try
+        {
+            st.executeUpdate("insert into days (dayinyear, yearnumber, semesterid) values (" + day.getDayinyear() + ", " + day.getYearnumber() + ", " + day.getSemesterid() + ")");
+            return getDay(day.getDayinyear(), day.getYearnumber(), day.getSemesterid());
+        } catch (SQLException e)
+        {
+            return null;
+        }
+    }
+
+    public Day getDay(int id)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from days where id=" + id);
+
+            return resultSetToDay(rs);
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+    public Day getDay(int dayinyear, int yearnumber, int semesterid)
+    {
+        try
+        {
+            ResultSet rs = st.executeQuery("select * from days where dayinyear =" + dayinyear + " and yearnumber =" + yearnumber + " and semesterid =" + semesterid);
+
+            return resultSetToDay(rs);
+        }
+        catch(Exception e)
+        {
+            return null;
+        }
+    }
+
+    private Day resultSetToDay(ResultSet rs)
+    {
+        try
+        {
+            rs.next();
+
+            return new Day(
+                    rs.getInt("id"),
+                    rs.getInt("dayinyear"),
+                    rs.getInt("yearnumber"),
+                    rs.getInt("semesterid")
+            );
+        } catch (SQLException e)
+        {
+            return null;
+        }
+    }

backend/src/main/java/com/example/backend/discard/Week/Week.java

@@ -0,0 +1,26 @@
+package com.example.backend.discard.Week;
+
+public class Week {
+
+    private int id;
+    private int semesterid;
+    private int weeknumber;
+
+    public Week(int id, int semesterid, int weeknumber) {
+        this.id = id;
+        this.semesterid = semesterid;
+        this.weeknumber = weeknumber;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public int getSemesterid() {
+        return semesterid;
+    }
+
+    public int getWeeknumber() {
+        return weeknumber;
+    }
+}

backend/src/main/java/com/example/backend/discard/WeekController.java

@@ -0,0 +1,59 @@
+package com.example.backend.discard;
+
+import com.example.backend.anwprj.Database.DataBaseHandler;
+import com.example.backend.anwprj.Users.User;
+import com.example.backend.anwprj.Users.UserPermissions;
+import com.example.backend.anwprj.Users.UserSessionIDHandler;
+import org.springframework.http.HttpStatus;
+import com.example.backend.discard.Week.Week;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.sql.SQLException;
+
+@RestController
+public class WeekController
+{
+
+//    private DataBaseHandler db;
+//
+//    {
+//        db = DataBaseHandler.getInstance();
+//    }
+//
+//    @CrossOrigin
+//    @GetMapping("/weeks")
+//    public ResponseEntity<Week> getWeek(
+//            @RequestParam(name="sessionid") String sessionID,
+//            @RequestParam(name="semesterid") int semesterID,
+//            @RequestParam(name="weeknumber") int weekNumber) throws SQLException {
+//        User u = UserSessionIDHandler.getUserBySessionID(sessionID);
+//
+//        if(u != null)
+//        {
+//            Week w = db.getWeek(semesterID,weekNumber);
+//
+//            if(w != null)
+//            {
+//                return new ResponseEntity<>(w, HttpStatus.OK);
+//            }
+//            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
+//        }
+//        return new ResponseEntity<>(HttpStatus.FORBIDDEN);
+//    }
+//
+//    @CrossOrigin
+//    @PostMapping("/weeks")
+//    public ResponseEntity<Week> addWeek(@RequestBody Week week, @RequestParam(name="sessionid") String sessionID)
+//    {
+//        User u = UserSessionIDHandler.getUserBySessionID(sessionID);
+//
+//        if(u !=null && u.getPermissions() == UserPermissions.admin.getValue())
+//        {
+//            return new ResponseEntity<>(db.addWeek(week), HttpStatus.OK);
+//        }
+//
+//        return new ResponseEntity<>(null, HttpStatus.FORBIDDEN);
+//    }
+}
+

backend/src/main/resources/application.properties

@@ -0,0 +1 @@
+

backend/src/test/java/com/example/backend/BackendApplicationTests.java

@@ -0,0 +1,15 @@
+package com.example.backend;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class BackendApplicationTests
+{
+
+    @Test
+    void contextLoads()
+    {
+    }
+
+}