Provide mock-like DB manager for integration testing

Reviewed-on: #2

.gitignore

@@ -1 +1,2 @@
+build/
 .gradle/

.gradle/buildOutputCleanup/cache.properties

@@ -1,2 +1,2 @@
-#Wed Dec 03 17:27:55 CET 2025
+#Wed Dec 03 20:34:21 CET 2025
 gradle.version=8.14

.idea/modules.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/modules/Template.test.iml" filepath="$PROJECT_DIR$/.idea/modules/Template.test.iml" />
+    </modules>
+  </component>
+</project>

.idea/modules/Template.test.iml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module version="4">
+  <component name="AdditionalModuleElements">
+    <content url="file://$MODULE_DIR$/../../src/test" dumb="true">
+      <sourceFolder url="file://$MODULE_DIR$/../../src/test/resources" type="java-test-resource" />
+    </content>
+  </component>
+</module>

build.gradle

@@ -14,6 +14,7 @@ dependencies {
     testImplementation platform('org.junit:junit-bom:5.10.0')
     testImplementation 'org.junit.jupiter:junit-jupiter'
     testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
+    implementation 'com.mysql:mysql-connector-j:9.5.0'
 }
 
 jacoco {

build/reports/tests/test/css/base-style.css

@@ -1,174 +0,0 @@
-
-body {
-    margin: 0;
-    padding: 0;
-    font-family: sans-serif;
-    font-size: 12pt;
-}
-
-body, a, a:visited {
-    color: #303030;
-}
-
-#content {
-    padding: 30px 50px;
-}
-
-#content h1 {
-    font-size: 160%;
-    margin-bottom: 10px;
-}
-
-#footer {
-    margin-top: 100px;
-    font-size: 80%;
-    white-space: nowrap;
-}
-
-#footer, #footer a {
-    color: #a0a0a0;
-}
-
-#line-wrapping-toggle {
-    vertical-align: middle;
-}
-
-#label-for-line-wrapping-toggle {
-    vertical-align: middle;
-}
-
-ul {
-    margin-left: 0;
-}
-
-h1, h2, h3 {
-    white-space: nowrap;
-}
-
-h2 {
-    font-size: 120%;
-}
-
-.tab-container .tab-container {
-    margin-left: 8px;
-}
-
-ul.tabLinks {
-    padding: 0;
-    margin-bottom: 0;
-    overflow: auto;
-    min-width: 800px;
-    width: auto;
-    border-bottom: solid 1px #aaa;
-}
-
-ul.tabLinks li {
-    float: left;
-    height: 100%;
-    list-style: none;
-    padding: 5px 10px;
-    border-radius: 7px 7px 0 0;
-    border: solid 1px transparent;
-    border-bottom: none;
-    margin-right: 6px;
-    background-color: #f0f0f0;
-}
-
-ul.tabLinks li.deselected > a {
-    color: #6d6d6d;
-}
-
-ul.tabLinks li:hover {
-    background-color: #fafafa;
-}
-
-ul.tabLinks li.selected {
-    background-color: #c5f0f5;
-    border-color: #aaa;
-}
-
-ul.tabLinks a {
-    font-size: 120%;
-    display: block;
-    outline: none;
-    text-decoration: none;
-    margin: 0;
-    padding: 0;
-}
-
-ul.tabLinks li h2 {
-    margin: 0;
-    padding: 0;
-}
-
-div.tab {
-}
-
-div.selected {
-    display: block;
-}
-
-div.deselected {
-    display: none;
-}
-
-div.tab table {
-    min-width: 350px;
-    width: auto;
-    border-collapse: collapse;
-}
-
-div.tab th, div.tab table {
-    border-bottom: solid 1px #d0d0d0;
-}
-
-div.tab th {
-    text-align: left;
-    white-space: nowrap;
-    padding-left: 6em;
-}
-
-div.tab th:first-child {
-    padding-left: 0;
-}
-
-div.tab td {
-    white-space: nowrap;
-    padding-left: 6em;
-    padding-top: 5px;
-    padding-bottom: 5px;
-}
-
-div.tab td:first-child {
-    padding-left: 0;
-}
-
-div.tab td.numeric, div.tab th.numeric {
-    text-align: right;
-}
-
-span.code {
-    display: inline-block;
-    margin-top: 0;
-    margin-bottom: 1em;
-}
-
-span.code pre {
-    font-size: 11pt;
-    padding: 10px;
-    margin: 0;
-    background-color: #f7f7f7;
-    border: solid 1px #d0d0d0;
-    min-width: 700px;
-    width: auto;
-}
-
-span.wrapped pre {
-    word-wrap: break-word;
-    white-space: pre-wrap;
-    word-break: break-all;
-}
-
-label.hidden {
-    display: none;
-}

build/tmp/.cache/expanded/zip_9892ccb804f78c0637616b68610d363f/META-INF/MANIFEST.MF

@@ -1,20 +0,0 @@
-Manifest-Version: 1.0
-Created-By: Apache Maven Bundle Plugin 6.0.0
-Build-Jdk-Spec: 21
-Build-Tool-Jdk-Spec: 21
-Automatic-Module-Name: org.jacoco.agent
-Bnd-LastModified: 1743583180503
-Bundle-Description: JaCoCo Agent
-Bundle-License: https://www.eclipse.org/legal/epl-2.0/
-Bundle-ManifestVersion: 2
-Bundle-Name: JaCoCo Agent
-Bundle-RequiredExecutionEnvironment: J2SE-1.5
-Bundle-SymbolicName: org.jacoco.agent
-Bundle-Vendor: Mountainminds GmbH & Co. KG
-Bundle-Version: 0.8.13.202504020838
-Eclipse-SourceReferences: scm:git:git://github.com/jacoco/jacoco.git;pat
- h="org.jacoco.agent";commitId=78d5eff856bbe6129f05012e40c13d1840e20598
-Export-Package: org.jacoco.agent;version="0.8.13"
-Require-Capability: osgi.ee;filter:="(&(osgi.ee=JavaSE)(version=1.5))"
-Tool: Bnd-7.0.0.202310060912
-

build/tmp/.cache/expanded/zip_9892ccb804f78c0637616b68610d363f/META-INF/maven/org.jacoco/org.jacoco.agent/pom.properties

@@ -1,3 +0,0 @@
-artifactId=org.jacoco.agent
-groupId=org.jacoco
-version=0.8.13

build/tmp/.cache/expanded/zip_9892ccb804f78c0637616b68610d363f/META-INF/maven/org.jacoco/org.jacoco.agent/pom.xml

@@ -1,106 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!--
-   Copyright (c) 2009, 2025 Mountainminds GmbH & Co. KG and Contributors
-   This program and the accompanying materials are made available under
-   the terms of the Eclipse Public License 2.0 which is available at
-   http://www.eclipse.org/legal/epl-2.0
-
-   SPDX-License-Identifier: EPL-2.0
-
-   Contributors:
-      Evgeny Mandrikov - initial API and implementation
--->
-<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 http://maven.apache.org/maven-v4_0_0.xsd">
-  <modelVersion>4.0.0</modelVersion>
-
-  <parent>
-    <groupId>org.jacoco</groupId>
-    <artifactId>org.jacoco.build</artifactId>
-    <version>0.8.13</version>
-    <relativePath>../org.jacoco.build</relativePath>
-  </parent>
-
-  <artifactId>org.jacoco.agent</artifactId>
-
-  <name>JaCoCo :: Agent</name>
-  <description>JaCoCo Agent</description>
-
-  <build>
-    <sourceDirectory>src</sourceDirectory>
-
-    <plugins>
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-dependency-plugin</artifactId>
-        <executions>
-          <execution>
-            <phase>prepare-package</phase>
-            <goals>
-              <goal>copy</goal>
-            </goals>
-            <configuration>
-              <artifactItems>
-                <artifactItem>
-                  <groupId>${project.groupId}</groupId>
-                  <artifactId>org.jacoco.agent.rt</artifactId>
-                  <classifier>all</classifier>
-                  <version>${project.version}</version>
-                  <destFileName>jacocoagent.jar</destFileName>
-                </artifactItem>
-              </artifactItems>
-              <outputDirectory>${project.build.directory}/classes</outputDirectory>
-              <overWriteReleases>false</overWriteReleases>
-              <overWriteSnapshots>false</overWriteSnapshots>
-              <overWriteIfNewer>true</overWriteIfNewer>
-            </configuration>
-          </execution>
-        </executions>
-      </plugin>
-
-      <plugin>
-        <groupId>org.codehaus.mojo</groupId>
-        <artifactId>build-helper-maven-plugin</artifactId>
-        <executions>
-          <execution>
-            <id>attach-artifacts</id>
-            <phase>package</phase>
-            <goals>
-              <goal>attach-artifact</goal>
-            </goals>
-            <configuration>
-              <artifacts>
-                <artifact>
-                  <file>${project.build.directory}/classes/jacocoagent.jar</file>
-                  <type>jar</type>
-                  <classifier>runtime</classifier>
-                </artifact>
-              </artifacts>
-            </configuration>
-          </execution>
-        </executions>
-      </plugin>
-
-      <plugin>
-        <groupId>org.apache.felix</groupId>
-        <artifactId>maven-bundle-plugin</artifactId>
-        <executions>
-          <execution>
-            <phase>process-classes</phase>
-            <goals>
-              <goal>manifest</goal>
-            </goals>
-          </execution>
-        </executions>
-      </plugin>
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-jar-plugin</artifactId>
-        <configuration>
-          <archive>
-            <manifestFile>${project.build.outputDirectory}/META-INF/MANIFEST.MF</manifestFile>
-          </archive>
-        </configuration>
-      </plugin>
-    </plugins>
-  </build>
-</project>

build/tmp/.cache/expanded/zip_9892ccb804f78c0637616b68610d363f/about.html

@@ -1,72 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
-<html>
-<head>
-<title>About</title>
-<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
-</head>
-<body lang="EN-US">
-<h2>About This Content</h2>
-
-<p>
-  2025/04/02
-</p>
-
-<h3>License</h3>
-
-<p>
-  All Content in this distribution is made available by Mountainminds GmbH &amp; Co.
-  KG, Munich. Unless otherwise indicated below, the Content is provided to you
-  under the terms and conditions of the Eclipse Public License Version 2.0
-  (&quot;EPL&quot;). A copy of the EPL is available at
-  <a href="https://www.eclipse.org/legal/epl-2.0/">https://www.eclipse.org/legal/epl-2.0/</a>.
-  For purposes of the EPL, "Program" will mean the Content.
-</p>
-
-<h3>Third Party Content</h3>
-
-<p>
-  The Content includes items that have been sourced from third parties as set
-  out below.
-</p>
-
-<h4>ASM</h4>
-
-<p>
-  <a href="https://asm.ow2.io/">ASM 9.8</a> is subject to the terms and
-  conditions of the following license:
-</p>
-
-<pre>
-ASM: a very small and fast Java bytecode manipulation framework
-Copyright (c) 2000-2011 INRIA, France Telecom
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions
-are met:
-1. Redistributions of source code must retain the above copyright
-   notice, this list of conditions and the following disclaimer.
-2. Redistributions in binary form must reproduce the above copyright
-   notice, this list of conditions and the following disclaimer in the
-   documentation and/or other materials provided with the distribution.
-3. Neither the name of the copyright holders nor the names of its
-   contributors may be used to endorse or promote products derived from
-   this software without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
-LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
-CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
-THE POSSIBILITY OF SUCH DAMAGE.
-</pre>
-
-
-</body>
-</html>

build/tmp/jar/MANIFEST.MF

@@ -1,2 +0,0 @@
-Manifest-Version: 1.0
-

git show bc0e30860cb3697296a4ef6ee22735a5c83cf522

@@ -0,0 +1,44 @@
+commit bc0e30860cb3697296a4ef6ee22735a5c83cf522 (HEAD -> database)
+Author: Riley Schneider <88947587+Ferryry@users.noreply.github.com>
+Date:   Wed Dec 3 17:30:33 2025 +0100
+
+    First database tests
+
+commit 26f7ecbee653b98739e75eb8c4707745f252a1a8 (origin/main, origin/HEAD, main)
+Merge: 668a76e2 eed1390c
+Author: Ferryry <rileymika99@gmail.com>
+Date:   Wed Dec 3 16:44:45 2025 +0100
+
+    Merge pull request 'Skeleton' (#1) from Skeleton into main
+    
+    Reviewed-on: https://home.luithardt.cloud:5400/KevinSchoenmayer/GseTDDUebungKCLR/pulls/1
+
+commit eed1390c6513f1b5e827fd6e09c91f54da7be463 (origin/Skeleton, Skeleton)
+Author: Riley Schneider <88947587+Ferryry@users.noreply.github.com>
+Date:   Wed Dec 3 16:42:41 2025 +0100
+
+    Remove database folder
+
+commit b732d8d4b50abc5893d138c6a574fef0025981e0
+Author: Riley Schneider <88947587+Ferryry@users.noreply.github.com>
+Date:   Wed Dec 3 16:38:10 2025 +0100
+
+    Initial Commit
+
+commit c5e26bf594b282ab3d665590d0535b61afa18247
+Author: KevinSchoenmayer <kschoenmay@stud.hs-heilbronn.de>
+Date:   Wed Dec 3 16:28:17 2025 +0100
+
+    Rough Skeleton for Tests and Classes
+
+commit 668a76e26cfd908499bb74a7732269206062df86
+Author: KevinSchoenmayer <kschoenmay@stud.hs-heilbronn.de>
+Date:   Wed Dec 3 15:26:09 2025 +0100
+
+    Initial Test Push
+
+commit 2d963c7fd8ab188625c0e2bc9203c4d55ee07aa3
+Author: KevinSchoenmayer <kschoenmay@stud.hs-heilbronn.de>
+Date:   Wed Dec 3 15:18:41 2025 +0100
+
+    Initial commit

src/main/java/hhn/temp/project/AssignmentManager.java

@@ -27,7 +27,7 @@ public class AssignmentManager {
         if (!workerMap.containsKey(workerId) || name == null || description == null) {
             throw new IllegalArgumentException("WorkerId must exist and name or description can't be null");
         }
-        Task task = new Task(++taskIdCounter, workerId, name, description, this);
+        Task task = new Task(++taskIdCounter, workerId, name, description);
         taskMap.put(taskIdCounter, task);
         return taskIdCounter;
     }

src/main/java/hhn/temp/project/Task.java

@@ -5,10 +5,8 @@ public class Task {
     String description;
     int taskId;
     int workerId;
-    AssignmentManager manager;
     TaskState state;
-    public Task(int taskId, int workerId, String name, String description, AssignmentManager manager) {
+    public Task(int taskId, int workerId, String name, String description) {
-        this.manager = manager;
         this.name = name;
         this.description = description;
         this.taskId = taskId;

src/main/java/hhn/temp/project/provider/Database.java

@@ -1,5 +1,29 @@
 package hhn.temp.project.provider;
 
+import java.io.IOException;
+import java.nio.file.Path;
+import java.sql.SQLException;
+
+/**
+ * A database interface with basic database connectivity
+ * @author Riley Schneider
+ */
 public interface Database {
-  public boolean connect();
+  /**
+   * Creates a connection to the database
+   * @throws SQLException Thrown if database error occurs
+   */
+  void connect() throws SQLException;
+
+  /**
+   * Closes a connection to the database
+   * @throws SQLException Thrown if database error occurs
+   */
+  void close() throws SQLException;
+
+  /**
+   * Clears the entire tables in the database and reset primary key counter to each table
+   * @throws SQLException Thrown if database error occurs
+   */
+  void clearDatabase() throws SQLException;
 }

src/main/java/hhn/temp/project/provider/DatabaseManager.java

@@ -1,10 +1,115 @@
 package hhn.temp.project.provider;
 
+import hhn.temp.project.Task;
+import hhn.temp.project.Worker;
+
+import java.sql.SQLException;
 import java.util.Collection;
 
-public interface DatabaseManager<E> extends Database {
+/**
-  public void saveObjects(Collection<E> objects);
+ * Simple Database Manager to handle simple command such as insertion, deletion, updating of Task and Worker objects.
-  public Collection<E> getObjects();
+ * @author Riley Schneider
-  public void saveObject(E object);
+ */
-  public E getObject(int id);
+public interface DatabaseManager extends Database {
+  /**
+   * Saves a Task object into the database
+   * @param task Task to be saved into the database
+   * @throws SQLException Thrown if database error occurs
+   */
+  void saveTask(Task task) throws SQLException;
+
+  /**
+   * Saves a collection of Task objects into the database
+   * @param tasks Tasks to be saved into the database
+   * @throws SQLException Thrown if database error occurs
+   */
+  void saveTasks(Collection<Task> tasks) throws SQLException;
+
+  /**
+   * Saves a Worker object into the database
+   * @param worker Worker to be saved into the database
+   * @throws SQLException Thrown if database error occurs
+   */
+  void saveWorker(Worker worker) throws SQLException;
+
+  /**
+   * Saves a collection Worker objects into the database
+   * @param workers Workers to be saved into the database
+   * @throws SQLException Thrown if database error occurs
+   */
+  void saveWorkers(Collection<Worker> workers) throws SQLException;
+
+  /**
+   * Updates a Task object that already exists in the database
+   * @param taskId The ID of the given task
+   * @param newTaskObject The new Task object that will overwrite the existent task on database
+   * @throws SQLException Thrown if database error occurs
+   */
+  void updateTask(int taskId, Task newTaskObject) throws  SQLException;
+
+  /**
+   * Updates a Worker object that already exists in the database
+   * @param workerId The ID of the given worker
+   * @param newWorkerObject The new Worker object that will overwrite the existent task on database
+   * @throws SQLException Thrown if database error occurs
+   */
+  void updateWorker(int workerId, Worker newWorkerObject) throws  SQLException;
+
+  /**
+   * Deletes a task from the database
+   * @param taskId The ID of the given task that needs to be deleted
+   * @throws SQLException Thrown if database error occurs
+   */
+  void deleteTask(int taskId) throws  SQLException;
+
+  /**
+   * Deletes a worker from the database
+   * @param workerId The ID of the given worker that needs to be deleted
+   * @throws SQLException Thrown if database error occurs
+   */
+  void deleteWorker(int workerId) throws  SQLException;
+
+  /**
+   * Gets a collection of all tasks available in the database
+   * @return A collection of tasks (empty if no task available)
+   * @throws SQLException Thrown if database error occurs
+   */
+  Collection<Task> getTasks() throws SQLException;
+
+  /**
+   * Gets a collection of all workers available in the database
+   * @return A collection of workers (empty if no task available)
+   * @throws SQLException Thrown if database error occurs
+   */
+  Collection<Worker> getWorkers() throws SQLException;
+
+  /**
+   * Gets a task given by its ID from the database
+   * @param taskId The task ID
+   * @return A task from the database (NULL if no task found)
+   * @throws SQLException Thrown if database error occurs
+   */
+  Task getTaskByTaskId(int taskId) throws SQLException;
+
+  /**
+   * Gets a worker given by its ID from the database
+   * @param workerId The worker ID
+   * @return A worker from the database (NULL if no worker found)
+   * @throws SQLException Thrown if database error occurs
+   */
+  Worker getWorkerByWorkerId(int workerId) throws SQLException;
+
+  /**
+   * Gets the total number of available tasks in the database.
+   * @return The total number of tasks (0 = zero entries; -1 = error)
+   * @throws SQLException Thrown if database error occurs
+   */
+  int getTotalNumberOfTasks() throws  SQLException;
+
+  /**
+   * Gets the total number of available workers in the database.
+   * @return The total number of workers (0 = zero entries; -1 = error)
+   * @throws SQLException Thrown if database error occurs
+   */
+  int getTotalNumberOfWorkers() throws  SQLException;
 }

src/main/java/hhn/temp/project/provider/SimpleDatabaseManager.java

@@ -0,0 +1,193 @@
+package hhn.temp.project.provider;
+
+import hhn.temp.project.Task;
+import hhn.temp.project.Worker;
+
+import java.sql.*;
+import java.util.*;
+
+public class SimpleDatabaseManager implements DatabaseManager {
+
+  private boolean connected = false;
+  private Map<Integer, Task> temporaryTaskList = new HashMap();
+  private Map<Integer, Worker> temporaryWorkerList = new HashMap<>();
+
+  @Override
+  public void saveTask(Task task) throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    if (!temporaryTaskList.containsKey(task.getTaskId())) {
+      temporaryTaskList.put(task.getTaskId(), task);
+    } else {
+      throw new SQLException("[INSERTION FAILED] Task with the same Task ID already exists.");
+    }
+  }
+
+  @Override
+  public void saveTasks(Collection<Task> tasks) throws SQLException {
+    for (Task task : tasks) {
+      saveTask(task);
+    }
+  }
+
+  @Override
+  public void saveWorker(Worker worker) throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    if (!temporaryWorkerList.containsKey(worker.getId())) {
+      temporaryWorkerList.put(worker.getId(), worker);
+    } else {
+      throw new SQLException("[INSERTION FAILED] Task with the same Task ID already exists.");
+    }
+  }
+
+  @Override
+  public void saveWorkers(Collection<Worker> workers) throws SQLException {
+    for (Worker worker : workers) {
+      saveWorker(worker);
+    }
+  }
+
+  @Override
+  public void updateTask(int taskId, Task newTaskObject) throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    if (temporaryTaskList.containsKey(taskId) && newTaskObject.getTaskId() == taskId) {
+      temporaryTaskList.remove(taskId);
+      temporaryTaskList.put(taskId, newTaskObject);
+      return;
+    }
+
+    throw new SQLException("[UPDATE FAILED] Task ID not found OR Task ID does not equal New Task ID.");
+  }
+
+  @Override
+  public void updateWorker(int workerId, Worker newWorkerObject) throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    if (temporaryWorkerList.containsKey(workerId) && newWorkerObject.getId() == workerId) {
+      temporaryWorkerList.remove(workerId);
+      temporaryWorkerList.put(workerId, newWorkerObject);
+      return;
+    }
+
+    throw new SQLException("[UPDATE FAILED] Worker ID not found OR Worker ID does not equal New Worker ID.");
+  }
+
+  @Override
+  public void deleteTask(int taskId) throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    if (temporaryTaskList.containsKey(taskId)) {
+      temporaryTaskList.remove(taskId);
+      return;
+    }
+
+    throw new SQLException("[DELETION FAILED] Could not find Task ID. Nothing to delete.");
+  }
+
+  @Override
+  public void deleteWorker(int workerId) throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    if (temporaryWorkerList.containsKey(workerId)) {
+      temporaryWorkerList.remove(workerId);
+      return;
+    }
+
+    throw new SQLException("[DELETION FAILED] Could not find Worker ID. Nothing to delete.");
+  }
+
+  @Override
+  public Collection<Task> getTasks() throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    return temporaryTaskList.values();
+  }
+
+  @Override
+  public Collection<Worker> getWorkers() throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    return temporaryWorkerList.values();
+  }
+
+  @Override
+  public Task getTaskByTaskId(int taskId) throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    if (temporaryTaskList.containsKey(taskId)) {
+      return temporaryTaskList.get(taskId);
+    }
+
+    throw new SQLException("[SELECTION FAILED] Could not find Task ID. Nothing to get.");
+  }
+
+  @Override
+  public Worker getWorkerByWorkerId(int workerId) throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    if (temporaryWorkerList.containsKey(workerId)) {
+      return temporaryWorkerList.get(workerId);
+    }
+
+    throw new SQLException("[SELECTION FAILED] Could not find Worker ID. Nothing to get.");
+  }
+
+  @Override
+  public int getTotalNumberOfTasks() throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    return temporaryTaskList.size();
+  }
+
+  @Override
+  public int getTotalNumberOfWorkers() throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    return temporaryWorkerList.size();
+  }
+
+  public void clearDatabase() throws SQLException {
+    if (!connected) {
+      throw new SQLException("[CONNECTION FAILED] Instance is not connected to database.");
+    }
+
+    temporaryTaskList.clear();
+    temporaryWorkerList.clear();
+  }
+
+  @Override
+  public void connect() throws SQLException {
+    connected = true;
+  }
+
+  @Override
+  public void close() throws SQLException {
+    connected = false;
+  }
+}

src/main/java/hhn/temp/project/provider/sql/createTaskTable.sql

@@ -0,0 +1,8 @@
+CREATE TABLE Task (
+    id INT AUTO_INCREMENT PRIMARY KEY,
+    taskid INT,
+    name VARCHAR(255) NOT NULL,
+    description TEXT,
+    workerid INT,
+    taskstate INT
+);

src/main/java/hhn/temp/project/provider/sql/deleteTaskTable.sql

@@ -0,0 +1 @@
+DELETE FROM Task WHERE taskid = ?

src/main/java/hhn/temp/project/provider/sql/insertTaskTable.sql

@@ -0,0 +1 @@
+INSERT INTO Task (taskid, name, description, workerid, taskstate) VALUES (?, ?, ?, ?, ?)

src/main/java/hhn/temp/project/provider/sql/selectTaskTable.sql

@@ -0,0 +1 @@
+SELECT * FROM Task WHERE workerid = ?

src/main/java/hhn/temp/project/provider/sql/updateTaskTable.sql

@@ -0,0 +1 @@
+UPDATE Task SET name = ?, description = ?, taskstate = ? WHERE taskid = ?

test/hhn/temp/project/DatabaseBadCasesTest.java

@@ -0,0 +1,46 @@
+package hhn.temp.project;
+
+import hhn.temp.project.provider.DatabaseManager;
+import hhn.temp.project.provider.SimpleDatabaseManager;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+import java.sql.SQLException;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class DatabaseBadCasesTest {
+
+  private DatabaseManager databaseManager;
+
+  @BeforeEach
+  public void setup() throws SQLException {
+    databaseManager = new SimpleDatabaseManager();
+    databaseManager.connect();
+    databaseManager.clearDatabase();
+  }
+
+  @Test
+  @DisplayName("Inserting Tasks with the same ID")
+  public void insertTasksWithTheSameId() throws SQLException {
+    Task task = new Task(10, 10, "ABC", "XYZ");
+    Task taskFaker = new Task(10, 5, "ABC!", "XYZ!");
+
+    databaseManager.saveTask(task);
+
+    databaseManager.saveTask(taskFaker);
+  }
+
+  @Test
+  @DisplayName("Inserting Workers with the same ID")
+  public void insertWorkersWithTheSameId() throws SQLException {
+    Worker worker = new Worker("Worker-1", 1);
+    Worker workerFaker = new Worker("Worker-100", 1);
+
+    databaseManager.saveWorker(worker);
+
+    databaseManager.saveWorker(workerFaker);
+  }
+}

test/hhn/temp/project/DatabaseGoodCasesTest.java

@@ -0,0 +1,86 @@
+package hhn.temp.project;
+
+import hhn.temp.project.provider.DatabaseManager;
+import hhn.temp.project.provider.SimpleDatabaseManager;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.io.IOException;
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+public class DatabaseGoodCasesTest {
+
+  private DatabaseManager databaseManager;
+
+  @BeforeEach
+  public void setup() throws SQLException {
+    databaseManager = new SimpleDatabaseManager();
+    databaseManager.connect();
+    databaseManager.clearDatabase();
+  }
+
+  @Test
+  @DisplayName("Inserting test task into the database and receiving back the same test task")
+  public void insertTaskAndReceiveItBackTest() throws SQLException {
+    Task task = new Task(123, 10, "Hello World", "Doing Something, hell yeah!");
+
+    databaseManager.saveTask(task);
+
+    Task reTask = databaseManager.getTaskByTaskId(task.getTaskId());
+
+    assertNotNull(reTask);
+    assertEquals(task.getTaskId(), reTask.getTaskId());
+    assertEquals(task.getDescription(), reTask.getDescription());
+    assertEquals(task.getName(), reTask.getName());
+    assertEquals(task.getWorkerId(), reTask.getWorkerId());
+
+    assertEquals(1, databaseManager.getTotalNumberOfTasks());
+  }
+
+  @Test
+  @DisplayName("Inserting test worker into the database and receiving back the same test worker")
+  public void insertWorkerAndReceivedItBackTest() throws SQLException {
+    Worker worker = new Worker("Worker-01", 12345678);
+
+    databaseManager.saveWorker(worker);
+
+    Worker reWorker = databaseManager.getWorkerByWorkerId(worker.getId());
+
+    assertNotNull(reWorker);
+
+    assertEquals(worker.getId(), reWorker.getId());
+    assertEquals(worker.getName(), reWorker.getName());
+  }
+
+  @Test
+  @DisplayName("Clearing the database (Task and Worker) test")
+  public void clearDatabaseTest() throws SQLException, InterruptedException {
+    Task task1 = new Task(10, 5, "Hello", "World");
+    Task task2 = new Task(9, 4, "Hochschule", "Heilbronn");
+    Task task3 = new Task(8, 9, "Gangnam", "Style");
+    Collection<Task> tasks = List.of(task1, task2, task3);
+
+    Worker worker1 = new Worker("ABC", 2);
+    Worker worker2 = new Worker("XYZ", 9);
+    Collection<Worker> workers = List.of(worker1, worker2);
+
+    databaseManager.saveTasks(tasks);
+    databaseManager.saveWorkers(workers);
+
+    Thread.sleep(500);
+
+    assertEquals(tasks.size(), databaseManager.getTotalNumberOfTasks());
+    assertEquals(workers.size(), databaseManager.getTotalNumberOfWorkers());
+
+    databaseManager.clearDatabase();
+
+    assertEquals(0, databaseManager.getTotalNumberOfTasks());
+    assertEquals(0, databaseManager.getTotalNumberOfWorkers());
+  }
+}