java二叉树的建立与应用代码

public class Tree {//定义一个二叉树类

private T root;

public T getRoot() {

return root;

}

public void setRoot(T root) {

this.root = root;

}

//get()函数与set()函数成对出现，来设定变量的值

public Tree getLeftChild() {

return leftChild;

}

public void setLeftChild(Tree leftChild) {

this.leftChild = leftChild;

}

public Tree getRight() {

return right;

}

public void setRight(Tree right) {

this.right = right;

}

private Tree leftChild;

private Tree right;

public Tree(T root) {

this.root= root;

}

public boolean isEmptyTree() {

return root==null;

}

public boolean exists(T data) {

if(root==null) return false;

if(data!=null) {

if(!isEmptyTree() && root.equals(data)) return true;//如果树不空，而且根等于data返回true

if(!leftChild.isEmptyTree() && leftChild.exists(data)) return true;

if(!right.isEmptyTree() && right.exists(data)) return true;

}

return false;

}

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

Tree a11 = new Tree("a11");

Tree a12 = new Tree("a12");

Tree a1 = new Tree("a1");

a1.setLeftChild(a11);

a1.setRight(a12);

Tree b11 = new Tree("b11");

Tree b1 = new Tree("b1");

b1.setRight(b11);

Tree a = new Tree("a");

a.setLeftChild(a1);

a.setRight(b1);

String c11 = null;//定义一个字符串型的变量c11，初始值为null

System.out.print(a.exists(c11));//判断二叉树a中是否含有c11

}

}