finished s05 ex2

05/src/main/java/ch/zhaw/ads/SortedBinaryTree.java

@@ -71,16 +71,18 @@ public class SortedBinaryTree<T extends Comparable<T>> implements Tree<T> {
     }
 
     public Traversal<T> traversal() {
-        // to be implemented
+        return new TreeTraversal<T>(root);
     }
 
     protected int calcHeight(TreeNode<T> node) {
         // to be implemented
+        return 0;
     }
 
 
     protected int calcSize(TreeNode p) {
         // to be implemented
+        return 0;
     }
 
     public int height() {

05/src/main/java/ch/zhaw/ads/TreeTraversal.java

@@ -1,5 +1,8 @@
 package ch.zhaw.ads;
 
+import java.util.LinkedList;
+import java.util.Queue;
+
 public class TreeTraversal<T extends Comparable<T>> implements Traversal<T> {
 
     private TreeNode<T> root;
@@ -8,16 +11,59 @@ public class TreeTraversal<T extends Comparable<T>> implements Traversal<T> {
         this.root = root;
     }
 
+    @Override
     public void inorder(Visitor<T> vis) {
-        // to be done
+        inorder(root, vis);
     }
 
+    private void inorder(TreeNode<T> node, Visitor<T> visitor) {
+        if (node != null) {
+            inorder(node.left, visitor);
+            visitor.visit(node.element);
+            inorder(node.right, visitor);
+        }
+    }
+
+    @Override
     public void preorder(Visitor<T> vis) {
-        // to be done
+        preorder(root, vis);
     }
 
+    private void preorder(TreeNode<T> node, Visitor<T> visitor) {
+        if (node != null) {
+            visitor.visit(node.element);
+            preorder(node.left, visitor);
+            preorder(node.right, visitor);
+        }
+    }
+
+    @Override
     public void postorder(Visitor<T> vis) {
-        // to be done
+        postorder(root, vis);
+    }
+
+    private void postorder(TreeNode<T> node, Visitor<T> visitor) {
+        if (node != null) {
+            postorder(node.left, visitor);
+            postorder(node.right, visitor);
+            visitor.visit(node.element);
+        }
+    }
+
+    @Override
+    public void levelorder(Visitor<T> vis) {
+        levelorder(root, vis);
+    }
+
+    void levelorder(TreeNode<T> node, Visitor<T> visitor) {
+        Queue<TreeNode<T>> q = new LinkedList<TreeNode<T>>();
+        if (node != null) q.offer(node);
+        while (!q.isEmpty()){
+            node = q.remove();
+            visitor.visit(node.element);
+            if (node.left !=null) q.offer(node.left);
+            if (node.right != null) q.offer(node.right);
+        }
     }
 
 }

05/src/test/java/ch/zhaw/ads/TreeTest.java

@@ -60,4 +60,4 @@ class MyVisitor<T> implements Visitor<T> {
     public String toString() {
         return output.toString();
     }
-}
+}