「java树形菜单算法」java实现菜单树
本篇文章给大家谈谈java树形菜单算法，以及java实现菜单树对应的知识点，希望对各位有所帮助，不要忘了收藏本站喔。
本文目录一览：
- 1、JSP动态树形菜单，菜单项从数据库中获得
- 2、用java 生成一个树形菜单
- 3、java 如何生成三级树形菜单？
- 4、java,jsp带checkbox的树形菜单，如何实现？
- 5、Java递归如何正确输出树形菜单
- 6、如何用Java实现树形结构啊？
JSP动态树形菜单，菜单项从数据库中获得
jsp动态树形菜单须用到递归算法，比如在数据库有张表，parent表，parent的字段有id,name,depth,leve,ID自增，depth设置为级数,如这条数据最大，为0,如为字菜单就为1,而leve就指定它父节点的id，给段代码自己可以摸索下 public Vector getModuleTree()
{
Vector pclass = new Vector();
try
{
stmt =con.createStatement();
String sql = "select * from Module where parentid = 0";
rs = stmt.executeQuery(sql);
Module cvo = null;
while(rs.next())
{
cvo = new Module();
cvo.setModule_id(rs.getInt("Module_id"));
cvo.setModule_name(rs.getString("Module_name"));
cvo.setModule_url(rs.getString("Module_url"));
cvo.setParentid(rs.getInt("parentid")); cvo.setRootid(rs.getInt("rootid")); cvo.setDepth(rs.getInt("depth")); pclass.add(cvo);
}
for (int i = 0; i pclass.size(); i++)
{
Module pcvo = (Module) pclass.get(i);
ShowTreeMenu(pcvo);
}
con.commit(); } catch (SQLException e)
{
e.printStackTrace();
} finally
{
try
{
if(rs!=null)
{
rs.close();
}
if(stmt!=null)
{
stmt.close();
}
if(con!=null)
{
con.close();
}
}
catch (SQLException e)
{
e.printStackTrace();
}
}
return classList;
}
public void ShowTreeMenu(Module c)
{
Module ccvo = null;
String sql = "select * from Module where parentid = " + c.getModule_id();
Vector cclass = new Vector();
try
{
Module cvotemp;
stmt =con.createStatement();
rs = stmt.executeQuery(sql);
while(rs.next())
{
cvotemp = new Module();
cvotemp.setModule_id(rs.getInt("Module_id"));
cvotemp.setModule_name(rs.getString("Module_name"));
cvotemp.setModule_url(rs.getString("Module_url"));
cvotemp.setParentid(rs.getInt("parentid")); cvotemp.setRootid(rs.getInt("rootid")); cvotemp.setDepth(rs.getInt("depth")); cclass.add(cvotemp);
}
System.out.println(cclass.size()+"(((((((((((((((((((((((((9");
if (cclass.size() 0)
{
c.setHasChild("have");
classList.add(c);
for (int j = 0; j cclass.size(); j++)
{
ccvo = (Module) cclass.get(j);
ShowTreeMenu(ccvo);
} } else
{
classList.add(c);
}
} catch (SQLException e)
{
e.printStackTrace();
}
}
用java 生成一个树形菜单
package com.csii;
import java.awt.GridLayout;
import javax.swing.JEditorPane;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreeSelectionModel;
public class TreeDemo1 extends JFrame implements TreeSelectionListener {
private static final long serialVersionUID = 1L;
private JPanel jContentPane = null;
private JTree jTree = null;
private JEditorPane jEditorPane = null;
private JScrollPane jScrollPane = null;
public JScrollPane getjScrollPane() {
if(jScrollPane==null){
jScrollPane = new JScrollPane();
jScrollPane.setViewportView(getJTree());
}
return jScrollPane;
}
DefaultMutableTreeNode top = null; // @jve:decl-index=0:
/**
* This is the default constructor
*/
public TreeDemo1() {
super();
initialize();
}
/**
* This method initializes this
*
* @return void
*/
private void initialize() {
this.setSize(438, 309);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setContentPane(getJContentPane());
this.setTitle("JFrame");
}
/**
* This method initializes jContentPane
*
* @return javax.swing.JPanel
*/
private JPanel getJContentPane() {
if (jContentPane == null) {
GridLayout gridLayout = new GridLayout();
gridLayout.setRows(1);
gridLayout.setColumns(2);
jContentPane = new JPanel();
jContentPane.setLayout(gridLayout);
jContentPane.add(getjScrollPane(), null);
jContentPane.add(getJEditorPane(), null);
}
return jContentPane;
}
/**
* This method initializes jTree
*
* @return javax.swing.JTree
*/
private JTree getJTree() {
if (jTree == null) {
top = new DefaultMutableTreeNode("黄山");
createNodes(top);
jTree = new JTree(top);
jTree.getSelectionModel().setSelectionMode(
TreeSelectionModel.SINGLE_TREE_SELECTION);
jTree.addTreeSelectionListener(this);
}
return jTree;
}
private void createNodes(DefaultMutableTreeNode top) {
DefaultMutableTreeNode jingdian = null, jiaotong = null, zhusu = null, binguan = null, luying = null, jiesu = null;
jingdian = new DefaultMutableTreeNode("景点");
jingdian.add(new DefaultMutableTreeNode("景点1"));
jingdian.add(new DefaultMutableTreeNode("景点2"));
jiaotong = new DefaultMutableTreeNode("交通");
jiaotong.add(new DefaultMutableTreeNode("路线1"));
jiaotong.add(new DefaultMutableTreeNode("路线2"));
jiaotong.add(new DefaultMutableTreeNode("路线3"));
zhusu = new DefaultMutableTreeNode("住宿");
zhusu.add(new DefaultMutableTreeNode("A住宿"));
zhusu.add(new DefaultMutableTreeNode("B住宿"));
zhusu.add(new DefaultMutableTreeNode("C住宿"));
binguan = new DefaultMutableTreeNode("宾馆");
binguan.add(new DefaultMutableTreeNode("X宾馆"));
binguan.add(new DefaultMutableTreeNode("Y宾馆"));
binguan.add(new DefaultMutableTreeNode("Z宾馆"));
binguan.add(new DefaultMutableTreeNode("XYZ宾馆"));
luying = new DefaultMutableTreeNode("露营");
luying.add(new DefaultMutableTreeNode("方式1"));
luying.add(new DefaultMutableTreeNode("方式2"));
jiesu = new DefaultMutableTreeNode("借宿");
jiesu.add(new DefaultMutableTreeNode("借宿1"));
jiesu.add(new DefaultMutableTreeNode("借宿2"));
jiesu.add(new DefaultMutableTreeNode("借宿3"));
top.add(jingdian);
top.add(jiaotong);
top.add(zhusu);
top.add(binguan);
top.add(luying);
top.add(jiesu);
}
/**
* This method initializes jEditorPane
*
* @return javax.swing.JEditorPane
*/
private JEditorPane getJEditorPane() {
if (jEditorPane == null) {
jEditorPane = new JEditorPane();
}
return jEditorPane;
}
@Override
public void valueChanged(TreeSelectionEvent e) {
DefaultMutableTreeNode node = (DefaultMutableTreeNode) jTree
.getLastSelectedPathComponent();
if (node == null)
// Nothing is selected.
return;
if(node.isRoot()){
jEditorPane.setText("黄山的简介");
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
}catch(Exception e){
e.printStackTrace();
}
new TreeDemo1().setVisible(true);
}
});
}
}
java 如何生成三级树形菜单？
是要返回一个json串吧。mybytis里设置好要返回自定义的结果集合。就直接可以
java,jsp带checkbox的树形菜单，如何实现？
jsp中带有checkbox的属性菜单需要用easyui组件来实现，代码如下：
!DOCTYPE html
html
head
meta charset="UTF-8"
titleCheckBox Tree - jQuery EasyUI Demo/title
link rel="stylesheet" type="text/css" href="../../themes/default/easyui.css"
link rel="stylesheet" type="text/css" href="../../themes/icon.css"
link rel="stylesheet" type="text/css" href="../demo.css"
script type="text/javascript" src="../../jquery.min.js"/script
script type="text/javascript" src="../../jquery.easyui.min.js"/script
/head
body
h2CheckBox Tree/h2
pTree nodes with check boxes./p
div style="margin:20px 0;"
a href="#" class="easyui-linkbutton" onclick="getChecked()"GetChecked/a
/div
div style="margin:10px 0"
input type="checkbox" checked onchange="$('#tt').tree({cascadeCheck:$(this).is(':checked')})"CascadeCheck
input type="checkbox" onchange="$('#tt').tree({onlyLeafCheck:$(this).is(':checked')})"OnlyLeafCheck
/div
div class="easyui-panel" style="padding:5px"
ul id="tt" class="easyui-tree" data-options="url:'tree_data1.json',method:'get',animate:true,checkbox:true"/ul
/div
script type="text/javascript"
function getChecked(){
var nodes = $('#tt').tree('getChecked');
var s = '';
for(var i=0; inodes.length; i++){
if (s != '') s += ',';
s += nodes[i].text;
}
alert(s);
}
/script
/body
/html
运行效果：
Java递归如何正确输出树形菜单
首先我们要建立树节点的类：
[java]
view
plain
copy
package
com.tree;
public
class
Node
{
private
Integer
id;
private
Integer
parentId;
private
String
name;
private
String
link;
public
Integer
getId()
{
return
id;
}
public
void
setId(Integer
id)
{
this.id
=
id;
}
public
Integer
getParentId()
{
return
parentId;
}
public
void
setParentId(Integer
parentId)
{
this.parentId
=
parentId;
}
public
String
getName()
{
return
name;
}
public
void
setName(String
name)
{
this.name
=
name;
}
public
String
getLink()
{
return
link;
}
public
void
setLink(String
link)
{
this.link
=
link;
}
}
输出树形菜单类：
[java]
view
plain
copy
package
com.tree;
import
java.util.ArrayList;
import
java.util.List;
public
class
Tree
{
private
StringBuffer
html
=
new
StringBuffer();
private
ListNode
nodes;
public
Tree(ListNode
nodes){
this.nodes
=
nodes;
}
public
String
buildTree(){
html.append("ul");
for
(Node
node
:
nodes)
{
Integer
id
=
node.getId();
if
(node.getParentId()
==
)
{
html.append("\r\nli
id='"
+
id
+
"'"
+
node.getName()+
"/li");
build(node);
}
}
html.append("\r\n/ul");
return
html.toString();
}
private
void
build(Node
node){
ListNode
children
=
getChildren(node);
if
(!children.isEmpty())
{
html.append("\r\nul");
for
(Node
child
:
children)
{
Integer
id
=
child.getId();
html.append("\r\nli
id='"
+
id
+
"'"
+
child.getName()+
"/li");
build(child);
}
html.append("\r\n/ul");
}
}
private
ListNode
getChildren(Node
node){
ListNode
children
=
new
ArrayListNode();
Integer
id
=
node.getId();
for
(Node
child
:
nodes)
{
if
(id.equals(child.getParentId()))
{
children.add(child);
}
}
return
children;
}
}
如何用Java实现树形结构啊？
package tree;
import java.util.LinkedList;
import java.util.List;
/**
* 功能：把一个数组的值存入二叉树中，然后进行3种方式的遍历
*
* 参考资料0:数据结构(C语言版)严蔚敏
*
* 参考资料1：
*
* 参考资料2：
*
* @author ocaicai@yeah.net @date: 2011-5-17
*
*/
public class BinTreeTraverse2 {
private int[] array = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
private static ListNode nodeList = null;
/**
* 内部类：节点
*
* @author ocaicai@yeah.net @date: 2011-5-17
*
*/
private static class Node {
Node leftChild;
Node rightChild;
int data;
Node(int newData) {
leftChild = null;
rightChild = null;
data = newData;
}
}
public void createBinTree() {
nodeList = new LinkedListNode();
// 将一个数组的值依次转换为Node节点
for (int nodeIndex = 0; nodeIndex array.length; nodeIndex++) {
nodeList.add(new Node(array[nodeIndex]));
}
// 对前lastParentIndex-1个父节点按照父节点与孩子节点的数字关系建立二叉树
for (int parentIndex = 0; parentIndex array.length / 2 - 1; parentIndex++) {
// 左孩子
nodeList.get(parentIndex).leftChild = nodeList
.get(parentIndex * 2 + 1);
// 右孩子
nodeList.get(parentIndex).rightChild = nodeList
.get(parentIndex * 2 + 2);
}
// 最后一个父节点:因为最后一个父节点可能没有右孩子，所以单独拿出来处理
int lastParentIndex = array.length / 2 - 1;
// 左孩子
nodeList.get(lastParentIndex).leftChild = nodeList
.get(lastParentIndex * 2 + 1);
// 右孩子,如果数组的长度为奇数才建立右孩子
if (array.length % 2 == 1) {
nodeList.get(lastParentIndex).rightChild = nodeList
.get(lastParentIndex * 2 + 2);
}
}
/**
* 先序遍历
*
* 这三种不同的遍历结构都是一样的，只是先后顺序不一样而已
*
* @param node
* 遍历的节点
*/
public static void preOrderTraverse(Node node) {
if (node == null)
return;
System.out.print(node.data + " ");
preOrderTraverse(node.leftChild);
preOrderTraverse(node.rightChild);
}
/**
* 中序遍历
*
* 这三种不同的遍历结构都是一样的，只是先后顺序不一样而已
*
* @param node
* 遍历的节点
*/
public static void inOrderTraverse(Node node) {
if (node == null)
return;
inOrderTraverse(node.leftChild);
System.out.print(node.data + " ");
inOrderTraverse(node.rightChild);
}
/**
* 后序遍历
*
* 这三种不同的遍历结构都是一样的，只是先后顺序不一样而已
*
* @param node
* 遍历的节点
*/
public static void postOrderTraverse(Node node) {
if (node == null)
return;
postOrderTraverse(node.leftChild);
postOrderTraverse(node.rightChild);
System.out.print(node.data + " ");
}
public static void main(String[] args) {
BinTreeTraverse2 binTree = new BinTreeTraverse2();
binTree.createBinTree();
// nodeList中第0个索引处的值即为根节点
Node root = nodeList.get(0);
System.out.println("先序遍历：");
preOrderTraverse(root);
System.out.println();
System.out.println("中序遍历：");
inOrderTraverse(root);
System.out.println();
System.out.println("后序遍历：");
postOrderTraverse(root);
}
}
java树形菜单算法的介绍就聊到这里吧，感谢你花时间阅读本站内容，更多关于java实现菜单树、java树形菜单算法的信息别忘了在本站进行查找喔。
发布于：2022-11-28，除非注明，否则均为原创文章，转载请注明出处。