Add Java-Kompendium book

Java-Kompendium/.gitignore

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+*.class

Java-Kompendium/kap3/HalloWelt.java

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+// OOP sucks.
+public class HalloWelt {
+    /**
+     * Java sucks.
+     *
+     * @param args Command line arguments.
+     */
+    public static void main(String[] args) {
+        System.out.print("Java sucks\n");
+    }
+}

Java-Kompendium/kap5/Task1.java

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+public class Task1 {
+    public static void main(String[] args) {
+        int x;
+        short y = 8;
+        long z;
+
+        x = y;
+        z = y;
+    }
+}

Java-Kompendium/kap5/Task2.java

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+import java.io.*;
+
+public class Task2 {
+    public static void main(String[] args) throws IOException {
+        System.out.print("Geben Sie eine Zahl ein: ");
+
+        var inputStream = new InputStreamReader(System.in);
+        var bufferedStream = new BufferedReader(inputStream);
+
+        String variable = bufferedStream.readLine();
+        int converted = Integer.parseInt(variable);
+
+        System.out.println("Der doppelte Wert ist: " + (converted * 2));
+    }
+}

Java-Kompendium/kap6/Task1.java

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+import java.util.*;
+
+public class Task1 {
+    public static void main(String[] args) {
+        ArrayList<String> workers = new ArrayList<>(6);
+
+        workers.add("Maximilian Mayer");
+        workers.add("Emil Faber");
+        workers.add("Anna Müller");
+        workers.add("Sebastian Waller");
+        workers.add("Oliver Stilz");
+        workers.add("Peter Huber");
+
+        print(workers);
+        System.out.println();
+
+        System.out.print("Der erste Name: ");
+        System.out.println(workers.get(0));
+
+        System.out.print("Der letzte Name: ");
+        System.out.println(workers.get(workers.size() - 1));
+
+        workers.set(3, "Frank Starke");
+
+        System.out.println();
+        print(workers);
+    }
+
+    public static void print(ArrayList<String> list) {
+        System.out.println(list.get(0));
+        System.out.println(list.get(1));
+        System.out.println(list.get(2));
+        System.out.println(list.get(3));
+        System.out.println(list.get(4));
+        System.out.println(list.get(5));
+    }
+}

Java-Kompendium/kap6/Task2.java

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+import java.util.*;
+import java.io.*;
+
+public class Task2 {
+    public static void main(String[] args) throws IOException {
+        var workers = new ArrayList<String>();
+        var stream = new InputStreamReader(System.in);
+        var bufferedStream = new BufferedReader(stream);
+
+        for (int i = 0; i < 5; ++i) {
+            workers.add(bufferedStream.readLine());
+        }
+        System.out.println("Folgende Mitarbeiter haben sie angegeben: " + workers);
+    }
+}

Java-Kompendium/kap6/Task3.java

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+import java.util.*;
+
+public class Task3 {
+    public static void main(String[] args) {
+        var javaList = new HashSet<String>(3);
+        var pythonList = new HashSet<String>(3);
+        var commonList = new HashSet<String>();
+        var differenceSet = new HashSet<String>();
+
+        javaList.add("Maximilian Mayer");
+        javaList.add("Emil Faber");
+        javaList.add("Anna Müller");
+
+        pythonList.add("Anna Müller");
+        pythonList.add("Sebastian Waller");
+        pythonList.add("Oliver Stilz");
+
+        commonList.addAll(javaList);
+        commonList.addAll(pythonList);
+
+        differenceSet.addAll(javaList);
+        differenceSet.retainAll(pythonList);
+
+        System.out.println("Java-Kurs: " + javaList);
+        System.out.println("Python-Kurs: " + pythonList);
+        System.out.println("Alle Teilnehmer: " + commonList);
+        System.out.println("Beide Kurse: " + differenceSet);
+    }
+}