Add chapters 9-17 for the java book

Java-Kompendium/kap8/Task1.java

@@ -0,0 +1,22 @@
+import java.io.*;
+import java.util.ArrayList;
+
+public class Task1 {
+    public static void main(String[] arguments) throws IOException {
+        String answer = "j";
+        var stream = new InputStreamReader(System.in);
+        var buffered = new BufferedReader(stream);
+        var names = new ArrayList<String>();
+
+        while (answer.equals("j")) {
+            System.out.println("Geben Sie einen Namen ein:");
+            names.add(buffered.readLine().strip());
+
+            System.out.println("Möchten sie fortsetzen? (j/n)");
+            answer = buffered.readLine().strip();
+        }
+        for (var name : names) {
+            System.out.println(name);
+        }
+    }
+}

Java-Kompendium/kap8/Task2.java

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+import java.io.*;
+
+public class Task2 {
+    public static void main(String[] arguments) throws IOException {
+        for (int i = 20; i >= 0; i = i - 2) {
+            System.out.print(i);
+            System.out.print(' ');
+        }
+        System.out.println();
+    }
+}

Java-Kompendium/kap8/Task3.java

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+import java.io.*;
+import java.util.HashMap;
+import java.util.Map;
+
+public class Task3 {
+    public static void main(String[] arguments) throws IOException {
+        var friends = new HashMap<String, Integer>();
+
+        friends.put("Maximilian Mayer", 20);
+        friends.put("Emil Faber", 30);
+        friends.put("Anna Müller", 45);
+        friends.put("Sebastian Waller", 39);
+        friends.put("Oliver Stilz", 25);
+
+        for (Map.Entry<String, Integer> name: friends.entrySet()) {
+            System.out.print(name.getKey());
+            System.out.print(": ");
+            System.out.println(name.getValue());
+        }
+    }
+}