Delete the root element from the tree.

2018-07-07 01:38:35 +02:00
parent b4969dd2b8
commit 76d17d75a8
3 changed files with 14 additions and 3 deletions
@@ -0,0 +1,130 @@
+package com.baeldung.tree;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+public class BinaryTreeUnitTest {
+
+    @Test
+    public void givenABinaryTree_WhenAddingElements_ThenTreeNotEmpty() {
+
+        BinaryTree bt = createBinaryTree();
+
+        assertTrue(!bt.isEmpty());
+    }
+
+    @Test
+    public void givenABinaryTree_WhenAddingElements_ThenTreeContainsThoseElements() {
+
+        BinaryTree bt = createBinaryTree();
+
+        assertTrue(bt.containsNode(6));
+        assertTrue(bt.containsNode(4));
+
+        assertFalse(bt.containsNode(1));
+    }
+
+    @Test
+    public void givenABinaryTree_WhenAddingExistingElement_ThenElementIsNotAdded() {
+
+        BinaryTree bt = createBinaryTree();
+
+        int initialSize = bt.getSize();
+
+        assertTrue(bt.containsNode(3));
+        bt.add(3);
+        assertEquals(initialSize, bt.getSize());
+    }
+
+    @Test
+    public void givenABinaryTree_WhenLookingForNonExistingElement_ThenReturnsFalse() {
+
+        BinaryTree bt = createBinaryTree();
+
+        assertFalse(bt.containsNode(99));
+    }
+
+    @Test
+    public void givenABinaryTree_WhenDeletingElements_ThenTreeDoesNotContainThoseElements() {
+
+        BinaryTree bt = createBinaryTree();
+
+        assertTrue(bt.containsNode(9));
+        bt.delete(9);
+        assertFalse(bt.containsNode(9));
+    }
+
+    @Test
+    public void givenABinaryTree_WhenDeletingNonExistingElement_ThenTreeDoesNotDelete() {
+
+        BinaryTree bt = createBinaryTree();
+
+        int initialSize = bt.getSize();
+
+        assertFalse(bt.containsNode(99));
+        bt.delete(99);
+        assertFalse(bt.containsNode(99));
+        assertEquals(initialSize, bt.getSize());
+    }
+
+    @Test
+    public void it_deletes_the_root() {
+        int value = 12;
+        BinaryTree bt = new BinaryTree();
+        bt.add(value);
+
+        assertTrue(bt.containsNode(value));
+        bt.delete(value);
+        assertFalse(bt.containsNode(value));
+    }
+
+    @Test
+    public void givenABinaryTree_WhenTraversingInOrder_ThenPrintValues() {
+
+        BinaryTree bt = createBinaryTree();
+
+        bt.traverseInOrder(bt.root);
+    }
+
+    @Test
+    public void givenABinaryTree_WhenTraversingPreOrder_ThenPrintValues() {
+
+        BinaryTree bt = createBinaryTree();
+
+        bt.traversePreOrder(bt.root);
+    }
+
+    @Test
+    public void givenABinaryTree_WhenTraversingPostOrder_ThenPrintValues() {
+
+        BinaryTree bt = createBinaryTree();
+
+        bt.traversePostOrder(bt.root);
+    }
+
+    @Test
+    public void givenABinaryTree_WhenTraversingLevelOrder_ThenPrintValues() {
+
+        BinaryTree bt = createBinaryTree();
+
+        bt.traverseLevelOrder();
+    }
+
+    private BinaryTree createBinaryTree() {
+        BinaryTree bt = new BinaryTree();
+
+        bt.add(6);
+        bt.add(4);
+        bt.add(8);
+        bt.add(3);
+        bt.add(5);
+        bt.add(7);
+        bt.add(9);
+
+        return bt;
+    }
+
+}