java代码实现树 java实现b树( 四 )


import java.awt.*;
import java.awt.event.*;
import java.util.*;public class TreeDemo1{
public TreeDemo1(){
JFrame f=new JFrame("TreeDemo1");
Container contentPane=f.getContentPane();
String[] s1={"公司文件","个人信件","私人文件"};
String[] s2={"本机磁盘(C:)","本机磁盘(D:)","本机磁盘(E:)"};
String[] s3={"奇摩站","职棒消息","网络书店"};
Hashtable hashtable1=new Hashtable();
Hashtable hashtable2=new Hashtable();
hashtable1.put("我的公文包",s1);
hashtable1.put("我的电脑",s2);
hashtable1.put("收藏夹",hashtable2);
hashtable2.put("网站列表",s3);
Font font = new Font("Dialog", Font.PLAIN, 12);
Enumeration keys = UIManager.getLookAndFeelDefaults().keys();
/**定义widnows界面**/
while (keys.hasMoreElements()) {
Object key = keys.nextElement();
if (UIManager.get(key) instanceof Font) {
UIManager.put(key, font);
}
}
try{
UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
}catch(Exception el){
System.exit(0);
}
/**定义widnows界面**/
JTree tree=new JTree(hashtable1);
JScrollPane scrollPane=new JScrollPane();
scrollPane.setViewportView(tree);
contentPane.add(scrollPane);
f.pack();
f.setVisible(true);
f.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
}
});
}
public static void main(String[] args){
new TreeDemo1();
}
}
用java怎么构造一个二叉树呢?java构造二叉树,可以通过链表来构造,如下代码:
public class BinTree {
public final static int MAX=40;
BinTree []elements = new BinTree[MAX];//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; //数据元数
private BinTree left,right; //指向左,右孩子结点的链
public BinTree()
{
}
public BinTree(Object data)
{ //构造有值结点
this.data = https://www.04ip.com/post/data;
left = right = null;
}
public BinTree(Object data,BinTree left,BinTree right)
{ //构造有值结点
this.data = https://www.04ip.com/post/data;
this.left = left;
this.right = right;
}
public String toString()
{
return data.toString();
}
//前序遍历二叉树
public static void preOrder(BinTree parent){
if(parent == null)
return;
System.out.print(parent.data+" ");
preOrder(parent.left);
preOrder(parent.right);
}
//中序遍历二叉树
public void inOrder(BinTree parent){
if(parent == null)
return;
inOrder(parent.left);
System.out.print(parent.data+" ");
inOrder(parent.right);
}
//后序遍历二叉树
public void postOrder(BinTree parent){
if(parent == null)
return;
postOrder(parent.left);
postOrder(parent.right);
System.out.print(parent.data+" ");
}
// 层次遍历二叉树
public void LayerOrder(BinTree parent)
{
elements[0]=parent;
front=0;rear=1;
while(frontrear)
{
try
{
if(elements[front].data!=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){break;}
}
}
//返回树的叶节点个数
public int leaves()
{
if(this == null)
return 0;
if(left == nullright == null)
return 1;
return (left == null ? 0 : left.leaves())+(right == null ? 0 : right.leaves());

推荐阅读