diff --git a/app/build.gradle b/app/build.gradle
index d5bf6f1..16f2780 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -20,6 +20,9 @@ repositories {
 dependencies {
     // This dependency is used by the application.
     implementation 'com.google.guava:guava:31.0.1-jre'
+    implementation 'org.junit.jupiter:junit-jupiter:5.9.0'
+    implementation 'org.junit.platform:junit-platform-engine:1.9.0'
+    implementation 'org.junit.platform:junit-platform-launcher:1.9.0'
 }
 
 testing {
diff --git a/app/src/main/java/ch/nuth/zhaw/exbox/AnyServer.java b/app/src/main/java/ch/nuth/zhaw/exbox/AnyServer.java
new file mode 100644
index 0000000..79bfb86
--- /dev/null
+++ b/app/src/main/java/ch/nuth/zhaw/exbox/AnyServer.java
@@ -0,0 +1,13 @@
+package ch.nuth.zhaw.exbox;
+
+/**
+ * AnyServer -- Praktikum Experimentierkasten -- ADS
+ *
+ */
+public class AnyServer implements CommandExecutor {
+    //----- Dies implementiert das CommandExecutor Interface.
+    @Override
+    public String execute(String command) {
+        return "Die Eingabe ist \"" + command + "\"\n";
+    }
+}
diff --git a/app/src/main/java/ch/nuth/zhaw/exbox/App.java b/app/src/main/java/ch/nuth/zhaw/exbox/App.java
index c13445c..29486bb 100644
--- a/app/src/main/java/ch/nuth/zhaw/exbox/App.java
+++ b/app/src/main/java/ch/nuth/zhaw/exbox/App.java
@@ -1,14 +1,13 @@
-/*
- * This Java source file was generated by the Gradle 'init' task.
- */
 package ch.nuth.zhaw.exbox;
 
+/**
+ * @author K. Rege
+ * @version 1.0 -- Experimentierkasten
+ */
 public class App {
-    public String getGreeting() {
-        return "Hello World!";
-    }
-
     public static void main(String[] args) {
-        System.out.println(new App().getGreeting());
+        ExBoxFrame f = new ExBoxFrame();
+        f.setLocationRelativeTo(null);
+        f.setVisible(true);
     }
-}
+}
\ No newline at end of file
diff --git a/app/src/main/java/ch/nuth/zhaw/exbox/CommandExecutor.java b/app/src/main/java/ch/nuth/zhaw/exbox/CommandExecutor.java
new file mode 100644
index 0000000..afc43f8
--- /dev/null
+++ b/app/src/main/java/ch/nuth/zhaw/exbox/CommandExecutor.java
@@ -0,0 +1,20 @@
+package ch.nuth.zhaw.exbox;
+
+/**
+ * CommandExecutor -- Praktikum Experimentierkasten -- SW3 Dieses Interface muss
+ * von jedem Server implementiert werden.
+ *
+ * @author E. Mumprecht
+ * @version 1.0 -- Geruest fuer irgendeinen Server
+ * @version 1.1 -- K. Rege Fehlerueckgabe hinzugefuegt
+ */
+public interface CommandExecutor {
+    /**
+     * execute -- nimmt eine Kommandozeile, tut irgendetwas gescheites, und
+     * berichtet das Resultat.
+     *
+     * @param command Kommandozeile
+     * @return Resultat, ueblicherweise eine oder mehrere Zeilen.
+     */
+    String execute(String command) throws Exception;
+}
\ No newline at end of file
diff --git a/app/src/main/java/ch/nuth/zhaw/exbox/ExBoxFrame.java b/app/src/main/java/ch/nuth/zhaw/exbox/ExBoxFrame.java
new file mode 100644
index 0000000..b765b30
--- /dev/null
+++ b/app/src/main/java/ch/nuth/zhaw/exbox/ExBoxFrame.java
@@ -0,0 +1,296 @@
+package ch.nuth.zhaw.exbox;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.awt.event.ItemEvent;
+import java.awt.event.ItemListener;
+import java.io.BufferedReader;
+import java.io.FileInputStream;
+import java.io.InputStreamReader;
+import java.net.URISyntaxException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Set;
+
+/**
+ * @(#)ExBoxFrame.java
+ *
+ * JFC ExBox application
+ *
+ * @author K.Rege
+ * @version	1.00 2014/2/3
+ * @version	1.01 2016/8/2
+ * @version	2.00 2017/8/30 Test
+ * @version	2.01 2018/2/5 AutoscaleFaktor
+ * @version	2.02 2018/3/12 Reconnect (inspired by S. Kunz)
+ * @version	2.03 2021/7/24 Test (repeat)
+ * @version	2.04 2021/9/11 Test as plugin
+ */
+public class ExBoxFrame extends JFrame implements ActionListener, ItemListener {
+	private final int UHDTHRESHOLD = 1920;
+	private final String STANDARDENCODING = "ISO-8859-1";
+
+	private JMenuItem connect, exit, open, test, retest, textView, graphicView, clear;
+	private JMenu menuServer;
+	private JButton enter;
+	private JTextField arguments;
+	private JComboBox<String> history;
+	private JTextArea output;
+	private JScrollPane scrollPane;
+	private CommandExecutor command;
+	private CommandExecutor unitTest;
+	private boolean graphicOn;
+	private GraphicPanel graphic;
+	private String lastServer;
+	private String lastTestFile;
+
+	public void setFontSize(int size) {
+		Set<Object> keySet = UIManager.getLookAndFeelDefaults().keySet();
+		for (Object key : keySet) {
+			if (key != null && key.toString().toLowerCase().contains("font")) {
+				Font font = UIManager.getDefaults().getFont(key);
+				if (font != null) {
+					font = font.deriveFont((float) size);
+					UIManager.put(key, font);
+				}
+			}
+		}
+	}
+
+	private void initMenu() {
+		JMenuBar menuBar = new JMenuBar();
+		setJMenuBar(menuBar);
+
+		JMenu menuFile = new JMenu("File");
+		menuBar.add(menuFile);
+		open = new JMenuItem("Open...");
+		open.addActionListener(this);
+		menuFile.add(open);
+		exit = new JMenuItem();
+		exit.setText("Exit");
+		exit.addActionListener(this);
+		menuFile.add(exit);
+
+		menuServer = new JMenu("Server");
+		menuBar.add(menuServer);
+		connect = new JMenuItem("Connect ...");
+		connect.addActionListener(this);
+		menuServer.add(connect);
+
+		JMenu menuView = new JMenu("View");
+		menuBar.add(menuView);
+		clear = new JMenuItem("Clear");
+		clear.addActionListener(this);
+		menuView.add(clear);
+		textView = new JMenuItem("Text");
+		textView.addActionListener(this);
+		menuView.add(textView);
+		graphicView = new JMenuItem("Graphic");
+		graphicView.addActionListener(this);
+		menuView.add(graphicView);
+	}
+
+	private void initJUnit() {
+		try {
+			unitTest = ServerFactory.createServer(getPathCompiled().resolve("ExBoxJUnit.class").toString());
+			test = new JMenuItem("Test ...");
+			test.addActionListener(this);
+			menuServer.add(test);
+			retest = new JMenuItem("Test");
+			retest.addActionListener(this);
+			menuServer.add(retest);
+		} catch (Exception e) {
+			warning("Test Plugin not found\n");
+		}
+	}
+
+	private void initComponents() {
+		setLayout(new BorderLayout());
+		output = new JTextArea();
+		scrollPane = new JScrollPane(output);
+		add(BorderLayout.CENTER, scrollPane);
+
+		JPanel panel = new JPanel(new BorderLayout());
+		panel.setBorder(BorderFactory.createEmptyBorder(4, 4, 4, 4));
+		arguments = new JTextField();
+		arguments.addActionListener(this);
+		panel.add(BorderLayout.CENTER, arguments);
+		enter = new JButton("enter");
+		enter.addActionListener(this);
+		panel.add(BorderLayout.EAST, enter);
+		history = new JComboBox<>();
+		history.addItemListener(this);
+		panel.add(BorderLayout.SOUTH, history);
+		add(BorderLayout.SOUTH, panel);
+	}
+
+	/**
+	 * get default path for file open dialog
+	 */
+	private Path getPathCompiled() {
+		try {
+			Path path = Paths.get(getClass().getProtectionDomain().getCodeSource().getLocation().toURI());
+			for (String part : getClass().getPackage().getName().split("\\.")) {
+				path = path.resolve(part);
+			}
+			return path;
+		} catch (URISyntaxException e) {
+			throw new RuntimeException(e);
+		}
+	}
+
+	/**
+	 * The constructor
+	 */
+	public ExBoxFrame() {
+		try {
+			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
+		} catch (Exception ex) {
+			ex.printStackTrace();
+		}
+		Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
+		double scaleFaktor = (screenSize.getWidth() <= UHDTHRESHOLD) ? 1 : 2;
+		setFontSize((int) (11 * scaleFaktor));
+		setSize(
+				new	Dimension((int) (400 * scaleFaktor), (int) (400 * scaleFaktor)));
+		setTitle("ExBox");
+		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+		initComponents();
+		initMenu();
+		initJUnit();
+	}
+
+	private void warning(String s) {
+		System.err.println("\nWARNING: " + s + "\n");
+	}
+
+	private void error(String s) {
+		output.append("\nERROR: " + s + "\n");
+	}
+
+	private void execute(String args) throws Exception {
+		if (lastServer != null) {
+			command = ServerFactory.createServer(lastServer);
+		}
+		if (!arguments.getText().equals(history.getItemAt(0))
+				&& !arguments.getText().equals(history.getSelectedItem())) {
+			history.insertItemAt(arguments.getText(), 0);
+		}
+		if (command == null) {
+			error("no Server connected");
+		} else {
+			String res = command.execute(args);
+			if (graphicOn) {
+				graphic.setFigure(res);
+			} else {
+				output.append(res);
+			}
+		}
+	}
+
+	private void setGraphicView() {
+		if (!graphicOn) {
+			remove(scrollPane);
+			graphic = new GraphicPanel();
+			output.removeNotify();
+			add(BorderLayout.CENTER, graphic);
+			graphicOn = true;
+			validate();
+			repaint();
+		}
+	}
+
+	private void setTextView() {
+		if (graphicOn) {
+			remove(graphic);
+			add(BorderLayout.CENTER, scrollPane);
+			graphicOn = false;
+			validate();
+			repaint();
+		}
+	}
+
+	private String openFileDialog(Path startDirectory, String pattern) {
+		FileDialog	fd = new FileDialog(this, "Open");
+		if (pattern != null) fd.setFile(pattern);
+		if (startDirectory != null) fd.setDirectory(startDirectory.toString());
+		fd.setVisible(true);
+		return  fd.getDirectory() + fd.getFile();
+	}
+
+	private void testCommand(boolean retest) throws Exception {
+		if (!retest) {
+			lastTestFile = openFileDialog(getPathCompiled(), "*test.class");
+		}
+		if (lastTestFile == null) {
+			output.append("ERROR no Test spezified\n");
+		} else if (unitTest != null) {
+			output.append(unitTest.execute(lastTestFile));
+		}
+	}
+
+	private void connectCommand() throws Exception {
+		String name = openFileDialog(getPathCompiled(), "*Server.class");
+		command = ServerFactory.createServer(name);
+		lastServer = name;
+		String fullClassName = command.getClass().getName();
+		String simpleClassName = fullClassName.substring(
+				fullClassName.lastIndexOf('.') + 1);
+		setTitle("ExBox connected to " + simpleClassName);
+
+	}
+
+	private void openFile()  throws Exception {
+		String name = openFileDialog(null, null);
+
+		try (BufferedReader br = new BufferedReader(
+				new InputStreamReader(new FileInputStream(name), STANDARDENCODING)))
+		{
+			StringBuilder b = new StringBuilder();
+			String line;
+			while ((line = br.readLine()) != null) {
+				b.append(line);
+				b.append('\n');
+			}
+			execute(b.toString());
+		}
+	}
+
+	public void	itemStateChanged(ItemEvent e) {
+		try {
+			arguments.setText((String) e.getItem());
+			execute(arguments.getText());
+		} catch (Throwable ex) {
+			error(ex.toString());
+		}
+	}
+
+	public void	actionPerformed(ActionEvent	e) {
+		try {
+			if ((e.getSource() == arguments) || (e.getSource() == enter)) {
+				execute(arguments.getText());
+			} else if (e.getSource() == connect) {
+				connectCommand();
+			} else if (e.getSource() == test) {
+				testCommand(false);
+			} else if (e.getSource() == retest) {
+				testCommand(true);
+			} else if (e.getSource() == open) {
+				openFile();
+			} else if (e.getSource() == textView) {
+				setTextView();
+			} else if (e.getSource() == graphicView) {
+				setGraphicView();
+			} else if (e.getSource() == clear) {
+				output.setText("");
+			} else if (e.getSource() == exit) {
+				System.exit(0);
+			}
+		} catch (Throwable ex) {
+			ex.printStackTrace();
+			error(ex.toString());
+		}
+	}
+}
\ No newline at end of file
diff --git a/app/src/main/java/ch/nuth/zhaw/exbox/ExBoxJUnit.java b/app/src/main/java/ch/nuth/zhaw/exbox/ExBoxJUnit.java
new file mode 100644
index 0000000..a4d7cfe
--- /dev/null
+++ b/app/src/main/java/ch/nuth/zhaw/exbox/ExBoxJUnit.java
@@ -0,0 +1,92 @@
+package ch.nuth.zhaw.exbox;
+
+import org.junit.platform.engine.TestDescriptor;
+import org.junit.platform.engine.TestExecutionResult;
+import org.junit.platform.engine.discovery.DiscoverySelectors;
+import org.junit.platform.launcher.Launcher;
+import org.junit.platform.launcher.LauncherDiscoveryRequest;
+import org.junit.platform.launcher.TestExecutionListener;
+import org.junit.platform.launcher.TestIdentifier;
+import org.junit.platform.launcher.core.LauncherDiscoveryRequestBuilder;
+import org.junit.platform.launcher.core.LauncherFactory;
+
+import java.io.*;
+import java.util.LinkedList;
+import java.util.List;
+
+public class ExBoxJUnit implements CommandExecutor {
+    @Override
+    public String execute(String testFile) throws Exception {
+        final List<String> successfulTests = new LinkedList<>();
+        final List<TestFailure> failedResults = new LinkedList<>();
+
+        StringBuilder output = new StringBuilder();
+
+        output.append("\nRUN TESTS ").append(new File(testFile).getName().split("\\.")[0]).append("\n");
+
+        LauncherDiscoveryRequest request = LauncherDiscoveryRequestBuilder.request()
+                .selectors(DiscoverySelectors.selectClass(ServerFactory.loadClass(testFile)))
+                .build();
+
+        Launcher launcher = LauncherFactory.create();
+        launcher.discover(request);
+        launcher.registerTestExecutionListeners(new TestExecutionListener() {
+            @Override
+            public void executionFinished(TestIdentifier testIdentifier, TestExecutionResult testExecutionResult) {
+                if (testIdentifier.getType() != TestDescriptor.Type.TEST) {
+                    return;
+                }
+
+                if (testExecutionResult.getStatus() == TestExecutionResult.Status.SUCCESSFUL) {
+                    successfulTests.add(testIdentifier.getDisplayName());
+                } else {
+                    failedResults.add(new TestFailure(testIdentifier.getDisplayName(),
+                            testExecutionResult.getThrowable().orElse(null)));
+                }
+            }
+        });
+        launcher.execute(request);
+
+        for (String testName : successfulTests) {
+            output.append(testName).append(": OK\n");
+        }
+        for (TestFailure result : failedResults) {
+            output.append(result.getName()).append(": ERROR\n");
+            String error = result.errorString();
+            if (!error.isEmpty()) {
+                output.append(error).append("\n");
+            }
+        }
+        boolean wasSuccessful = failedResults.isEmpty();
+        output.append("TESTS ").append(wasSuccessful ? "PASSED" : "FAILED").append(": ")
+                .append(wasSuccessful ? "OK \u263a" : failedResults.size() + " ERRORS").append("\n");
+        return output.toString();
+    }
+
+    private static class TestFailure {
+        private final String name;
+        private final Throwable throwable;
+
+        TestFailure(String name, Throwable throwable) {
+            this.name = name;
+            this.throwable = throwable;
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public String errorString() {
+            if (throwable == null) {
+                return "";
+            }
+            try (StringWriter stringWriter = new StringWriter();
+                 PrintWriter printWriter = new PrintWriter(stringWriter)) {
+                throwable.printStackTrace(printWriter);
+                return stringWriter.toString();
+            } catch (IOException e) {
+                throw new UncheckedIOException(e);
+            }
+        }
+    }
+}
diff --git a/app/src/main/java/ch/nuth/zhaw/exbox/GraphicPanel.java b/app/src/main/java/ch/nuth/zhaw/exbox/GraphicPanel.java
new file mode 100644
index 0000000..1160702
--- /dev/null
+++ b/app/src/main/java/ch/nuth/zhaw/exbox/GraphicPanel.java
@@ -0,0 +1,84 @@
+package ch.nuth.zhaw.exbox;
+
+import javax.swing.*;
+import java.awt.*;
+import java.util.StringTokenizer;
+
+public class GraphicPanel extends JPanel {
+	String figure;
+
+	public void setFigure(String figure) {
+		this.figure = figure;
+		paint(getGraphics());
+	}
+
+	private void drawRect(Graphics g, double x, double y, double width, double height, String style) {
+		int w = getWidth();
+		int h = getHeight();
+		int ix0 = (int) (w * x);
+		int iy0 = (int) (h * y);
+		int ix1 = (int) (w * (x + width));
+		int iy1 = (int) (h * (y + height));
+		if (style.equals("draw")) {
+			g.drawRect(ix0, h - iy1, ix1 - ix0, iy1 - iy0);
+		} else {
+			g.fillRect(ix0, h - iy1, ix1 - ix0, iy1 - iy0);
+		}
+	}
+
+	private void drawFigure(Graphics g) {
+		if (figure != null) {
+			int w = getWidth();
+			int h = getHeight();
+			g.setColor(Color.black);
+			StringTokenizer tok = new StringTokenizer(figure, " <>=/,\"\n");
+			while (tok.hasMoreTokens()) {
+				String fig = tok.nextToken();
+				if (fig.equals("line")) {
+					tok.nextToken();
+					double x1 = Double.parseDouble(tok.nextToken());
+					tok.nextToken();
+					double y1 = Double.parseDouble(tok.nextToken());
+					tok.nextToken();
+					double x2 = Double.parseDouble(tok.nextToken());
+					tok.nextToken();
+					double y2 = Double.parseDouble(tok.nextToken());
+					g.drawLine((int) (x1 * w), h - (int) (y1 * h),
+							(int) (x2 * w), h - (int) (y2 * h));
+				} else if (fig.equals("rect")) {
+					tok.nextToken();
+					double x = Double.parseDouble(tok.nextToken());
+					tok.nextToken();
+					double y = Double.parseDouble(tok.nextToken());
+					tok.nextToken();
+					double width = Double.parseDouble(tok.nextToken());
+					tok.nextToken();
+					double height = Double.parseDouble(tok.nextToken());
+					tok.nextToken();
+					String style = tok.nextToken();
+					drawRect(g, x, y, width, height, style);
+				} else if (fig.equals("color")) {
+					tok.nextToken();
+					int red = Integer.parseInt(tok.nextToken());
+					tok.nextToken();
+					int green = Integer.parseInt(tok.nextToken());
+					tok.nextToken();
+					int blue = Integer.parseInt(tok.nextToken());
+					g.setColor(new Color(red, green, blue));
+				}
+			}
+		}
+	}
+
+	private void clear(Graphics g) {
+		int w = getWidth();
+		int h = getHeight();
+		g.setColor(new Color(240, 240, 240));
+		g.fillRect(0, 0, w, h);
+	}
+
+	public void paint(Graphics g) {
+		clear(g);
+		drawFigure(g);
+	}
+}
\ No newline at end of file
diff --git a/app/src/main/java/ch/nuth/zhaw/exbox/ServerFactory.java b/app/src/main/java/ch/nuth/zhaw/exbox/ServerFactory.java
new file mode 100644
index 0000000..9526e2c
--- /dev/null
+++ b/app/src/main/java/ch/nuth/zhaw/exbox/ServerFactory.java
@@ -0,0 +1,76 @@
+package ch.nuth.zhaw.exbox;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+
+/**
+ * Classloader that handles file path of class
+ */
+class MyClassLoader extends ClassLoader {
+    private String path;
+
+    MyClassLoader(ClassLoader parent) {
+        super(parent);
+    }
+
+    /**
+     * @param name filename of class
+     * return content of file as array of bytes; if file does not exist return null
+     */
+    private byte[] getBytes(String name) {
+        try {
+            System.out.println(name);
+            RandomAccessFile file = new RandomAccessFile(name, "r");
+            byte[] data = new byte[(int) file.length()];
+            file.readFully(data);
+            file.close();
+            return data;
+        } catch (IOException e) {
+        }
+        return null;
+    }
+
+    /**
+     * @param name filename of class
+     */
+    public Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException {
+        System.out.println("load:" + name + " " + resolve);
+        Class<?> clazz;
+        byte[] classData = getBytes(name);
+        if (classData != null) {
+            clazz = defineClass(null, classData, 0, classData.length);
+            path = name.substring(0,
+                    name.length() - clazz.getName().length() - ".class".length());
+            return clazz;
+        }
+        if (!resolve) {
+            classData = getBytes(
+                    path + name.replace(".", File.separator) + ".class");
+            if (classData != null) {
+                return defineClass(null, classData, 0, classData.length);
+            }
+        }
+        return findSystemClass(name);
+    }
+}
+
+/**
+ * ServerFactory -- Praktikum Experimentierkasten --
+ *
+ * @author K. Rege
+ * @version 1.0 -- Factory zur Erstellung von Server Objekten
+ * @version 2.0 -- Dynamisches Nachladen
+ * @version 2.01 -- Fix deprecated Functions
+ */
+public class ServerFactory {
+    public static Class<?> loadClass(String name) throws Exception {
+        MyClassLoader myClassLoader = new MyClassLoader(
+                MyClassLoader.class.getClassLoader());
+        return myClassLoader.loadClass(name, true);
+    }
+
+    public static CommandExecutor createServer(String name) throws Exception {
+        return (CommandExecutor) loadClass(name).getConstructor(new Class[]{}).newInstance();
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/ch/nuth/zhaw/exbox/Stack.java b/app/src/main/java/ch/nuth/zhaw/exbox/Stack.java
new file mode 100644
index 0000000..9cde4fd
--- /dev/null
+++ b/app/src/main/java/ch/nuth/zhaw/exbox/Stack.java
@@ -0,0 +1,49 @@
+package ch.nuth.zhaw.exbox;
+
+/**
+ * Interface für Abstrakten Datentyp (ADT) Stack
+ */
+public interface Stack {
+    /**
+     * Legt eine neues Objekt auf den Stack, falls noch nicht voll.
+     *
+     * @param x ist das Objekt, das dazugelegt wird.
+     */
+    void push(Object x) throws StackOverflowError;
+
+    /**
+     * Entfernt das oberste und damit das zuletzt eingefügte Objekt.
+     * Ist der Stack leer, wird null zurückgegeben.
+     *
+     * @return Gibt das oberste Objekt zurück oder null, falls leer.
+     */
+    Object pop();
+
+    /**
+     * Testet, ob der Stack leer ist.
+     *
+     * @return Gibt true zurück, falls der Stack leer ist.
+     */
+    boolean isEmpty();
+
+    /**
+     * Gibt das oberste Objekt zurück, ohne es zu entfernen.
+     * Ist der Stack leer, wird null zurückgegeben.
+     *
+     * @return Gibt das oberste Objekt zurück oder null, falls leer.
+     */
+    Object peek();
+
+    /**
+     * Entfernt alle Objekte vom Stack. Ein Aufruf von isEmpty()
+     * ergibt nachher mit Sicherheit true.
+     */
+    void removeAll();
+
+    /**
+     * Testet, ob der Stack voll ist.
+     *
+     * @return Gibt true zurück, falls der Stack voll ist.
+     */
+    boolean isFull();
+}
\ No newline at end of file
diff --git a/app/src/test/java/ch/nuth/zhaw/exbox/AppTest.java b/app/src/test/java/ch/nuth/zhaw/exbox/AppTest.java
deleted file mode 100644
index fa62a74..0000000
--- a/app/src/test/java/ch/nuth/zhaw/exbox/AppTest.java
+++ /dev/null
@@ -1,14 +0,0 @@
-/*
- * This Java source file was generated by the Gradle 'init' task.
- */
-package ch.nuth.zhaw.exbox;
-
-import org.junit.jupiter.api.Test;
-import static org.junit.jupiter.api.Assertions.*;
-
-class AppTest {
-    @Test void appHasAGreeting() {
-        App classUnderTest = new App();
-        assertNotNull(classUnderTest.getGreeting(), "app should have a greeting");
-    }
-}