二叉树的JAVA实现

二叉树的JAVA实现功能：1.构建叶子节点/*** 叶子节点就只有数据域，左右子树都是空的。

* @param tree*/public BinaryTree(Object tree){this.data = data;left = right = null;}2.构造一棵带左右子树的树/*** @param data* @param tree*/public BinaryTree(Object data , BinaryTree tree){this.data = data;this.left = left;this.right = right;}3.遍历二叉树（先序，中序，后序）（1），先序遍历/*** 先序遍历的顺序为：根节点---左子树---右子树* 如果根节点有数据，直接打印，再访问左子树，之后是右子树 * @param root*/public void preOrder(BinaryTree root){if(root == null){return ;}else{System.out.println(root.data+"");preOrder(root.left);preOrder(root.right);}}（2）中序遍历/*** 中序遍历：左子树---根节点---右子树* @param root*/public void inOrder(BinaryTree root){if(root == null){return;}else{inOrder(root.left);System.out.println(root.data+"");inOrder(root.right);}}（3），后序遍历/*** 后序遍历：右子树---左子树---根节点* @param root*/public void postOrder(BinaryTree root){if(root == null){return;}else{postOrder(root.left);postOrder(root.right);System.out.println(root.data + "");}}（4）层次遍历/*** 层次遍历* @param root*/public void layoutOrder(BinaryTree root) {elements[0] = root;front = 0;rear = 1;while (front < rear) {try {if (elements[front] != null) {System.out.println(elements[front].data + "");if (elements[front].left != null) {elements[rear++] = elements[front].left;}if (elements[front].right != null) {elements[rear++] = elements[front].right;}front++;}} catch (Exception e) {e.printStackTrace();}}}4，求叶子节点的数量/*** 返回叶子节点的数目如果左子树和右子树均为空，数量+1,** @return*/public int leaves() {if (this == null)return 0;if (left == null && right == null) {return 1;} else {return (left == null ? 0 : left.leaves())+ (right == null ? 0 : right.leaves());}}5.求树的深度/*** @return*/public int height(){int heightOfTree;if(this == null){return -1;}int leftHeight = (left == null ? 0 : left.height());int rightHeight = (right == null ? 0 : right.height());heightOfTree = leftHeight < rightHeight ? rightHeight : leftHeight ;return 1+ heightOfTree ;}6.求某一节点所在的层次public int level(Object object) {int levelInTree;if (this == null)return -1;if (object == data)return 1;// 规定根节点为第一层int leftLevel = (left == null ? -1 : left.level(object));int rightLevel = (right == null ? -1 : right.level(object));if (leftLevel < 0 && rightLevel < 0)return -1;levelInTree = leftLevel < rightLevel ? rightLevel : leftLevel;return 1 + levelInTree;}7.调换左右子树的位置public void reflect(){if(this == null){return ;}if(left != null){left.reflect();}if(right != null){right.reflect();}BinaryTree temp = left;left = right;right = temp;}8.移除对应的树/*** 移除节点，同时删除树*/public void defoliate(){if(this == null){return ;}if(left == null && right == null){System.out.println(this + "");data = null;return;}if(left != null){left.defoliate();left = null;}data = null;if(right != null){right.defoliate();right = null;}}=================以下是完整的代码package arithmetic;/*** 二叉树的JAVA实现 1.新建一个二叉树类 2.新建一个空的二叉树（叶子节点）** @author 海浪之心**/public class BinaryTree {public final static int MAX = 40;BinaryTree[] elements = new BinaryTree[40]; // 用于层次遍历时保存各个节点int front; // 层次遍历时队首int rear; // 层次遍历时队尾private Object data; // 用于保存树的数据域private BinaryTree left, right; // 二叉的左右子树/*** 构造叶子节点叶子节点就只有数据域，左右子树都是空的。

** @param tree*/public BinaryTree(Object data) {this.data = data;left = right = null;}/*** 构造一棵带左右子树的树** @param data* @param tree*/public BinaryTree(Object data, BinaryTree left, BinaryTree right) { this.data = data;this.left = left;this.right = right;}/*** 覆盖原有的toString方法*/public String toString() {return data.toString();}/*** 先序遍历先序遍历的顺序为：根节点---左子树---右子树如果根节点有数据，直接打印，再访问左子树，之后是右子树** @param root*/public void preOrder(BinaryTree root) {if (root == null) {return;} else {System.out.print(root.data + " ");preOrder(root.left);preOrder(root.right);}}/*** 中序遍历：左子树---根节点---右子树** @param root*/public void inOrder(BinaryTree root) { if (root == null) {return;} else {inOrder(root.left);System.out.print(root.data + " ");inOrder(root.right);}}/*** 后序遍历：右子树---左子树---根节点** @param root*/public void postOrder(BinaryTree root) { if (root == null) {return;} else {postOrder(root.left);postOrder(root.right);System.out.print(root.data + " ");}}/*** 层次遍历 layerOrder** @param root*/public void layerOrder(BinaryTree root) { elements[0] = root;front = 0;rear = 1;while (front < rear) {try {if (elements[front] != null) {System.out.print(elements[front].data + " ");if (elements[front].left != null) {elements[rear++] = elements[front].left;}if (elements[front].right != null) {elements[rear++] = elements[front].right;}front++;}} catch (Exception e) {e.printStackTrace();}}}/*** 返回叶子节点的数目如果左子树和右子树均为空，数量+1,** @return*/public int leaves() {if (this == null)return 0;if (left == null && right == null) {return 1;} else {return (left == null ? 0 : left.leaves())+ (right == null ? 0 : right.leaves());}}/*** 求树的深度** @return*/public int height() {int heightOfTree;if (this == null) {return -1;}int leftHeight = (left == null ? 0 : left.height());int rightHeight = (right == null ? 0 : right.height());heightOfTree = leftHeight < rightHeight ? rightHeight : leftHeight;return 1 + heightOfTree;}/*** 调换左右子树的位置*/public void reflect() {if (this == null) {return;}if (left != null) {left.reflect();}if (right != null) {right.reflect();}BinaryTree temp = left;left = right;right = temp;}/*** 如果对象不在树中,结果返回-1;否则结果返回该对象在树中所处的层次,规定根节点为第一层** @param object* @return*/public int level(Object object) {int levelInTree;if (this == null)return -1;if (object == data)return 1;// 规定根节点为第一层int leftLevel = (left == null ? -1 : left.level(object));int rightLevel = (right == null ? -1 : right.level(object));if (leftLevel < 0 && rightLevel < 0)return -1;levelInTree = leftLevel < rightLevel ? rightLevel : leftLevel;return 1 + levelInTree;}/*** 移除节点，同时删除树*/public void defoliate() {if (this == null) {return;}if (left == null && right == null) {System.out.println(this + " aaa ");data = null;return;}if (left != null) {left.defoliate();left = null;}data = null;if (right != null) {right.defoliate();right = null;}}public static void test() {// TODO Auto-generated method stubBinaryTree e = new BinaryTree("E");BinaryTree g = new BinaryTree("G");BinaryTree h = new BinaryTree("H");BinaryTree i = new BinaryTree("I");BinaryTree d = new BinaryTree("D", null, g);BinaryTree f = new BinaryTree("F", h, i);BinaryTree b = new BinaryTree("B", d, e);BinaryTree c = new BinaryTree("C", f, null);BinaryTree tree = new BinaryTree("A", b, c);System.out.println("前序遍历二叉树结果: ");tree.preOrder(tree);System.out.println("\n中序遍历二叉树结果: ");tree.inOrder(tree);System.out.println("\n后序遍历二叉树结果: ");tree.postOrder(tree);System.out.println("\n层次遍历二叉树结果: ");yerOrder(tree);System.out.println("\nF所在的层次: " + tree.level("F"));System.out.println("\n这棵二叉树的高度: " + tree.height());System.out.println("--------------------------------------");tree.reflect();System.out.println("\n交换每个节点的孩子节点后......");System.out.println("\n前序遍历二叉树结果: ");tree.preOrder(tree);System.out.println("\n中序遍历二叉树结果: ");tree.inOrder(tree);System.out.println("\n后序遍历二叉树结果: ");tree.postOrder(tree);System.out.println("\n层次遍历二叉树结果: ");yerOrder(tree);System.out.println("\nF所在的层次: " + tree.level("F"));System.out.println("\n这棵二叉树的高度: " + tree.height());}/*** 测试函数** @param args*/public static void main(String[] args) {test();}}。