ext 后台查数据库数据拼装tree数据
来自：Extjs交流群(164648099)
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说明：
两个文件
jackyNode.java? treeVO对象 将数据库当中的树的数据库存入此
jackytree.java? 采用递归算法 将一次性查出来的数据生成treeJSON结构
直接将两个文件复制到eclipse中? run as即可查看
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jackyNode.java
package com.codeasy.common;public class jackyNode {private int id;private int parentId;private String text;jackyNode(){}jackyNode(int id,int parentId,String text){this.id=id;this.parentId = parentId;this.text = text;}public int getId() {return id;}public void setId(int id) {this.id = id;}public int getParentId() {return parentId;}public void setParentId(int parentId) {this.parentId = parentId;}public String getText() {return text;}public void setText(String text) {this.text = text;}}?
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jackytree.java?
package com.codeasy.common;import java.util.ArrayList;import java.util.Iterator;import java.util.List;/* * 数据库中的表结构是这样的 * id parentid name * * * */public class jackytree {List nodeList =new ArrayList();jackytree(){//构造方法里初始化模拟ListjackyNode node1 = new jackyNode(1,0,"根节点"); jackyNode node2 = new jackyNode(2,1,"一级菜单"); jackyNode node3 = new jackyNode(3,1,"一级菜单"); jackyNode node4 = new jackyNode(4,2,"二级菜单"); jackyNode node5 = new jackyNode(5,2,"二级菜单"); jackyNode node6 = new jackyNode(6,2,"二级菜单"); jackyNode node7 = new jackyNode(7,6,"三级菜单"); jackyNode node8 = new jackyNode(8,6,"三级菜单"); nodeList.add(node1); nodeList.add(node2); nodeList.add(node3); nodeList.add(node4); nodeList.add(node5); nodeList.add(node6); nodeList.add(node7); nodeList.add(node8); }StringBuffer returnStr=new StringBuffer(); public void recursionFn(List list , jackyNode node){ if(hasChild(list,node)){ returnStr.append("{id:"); returnStr.append(node.getId()); returnStr.append(",text:'"); returnStr.append(node.getText()); returnStr.append("'"); returnStr.append(",children:["); List childList = getChildList(list,node); Iterator it = childList.iterator(); while(it.hasNext()){ jackyNode n = (jackyNode)it.next(); recursionFn(list,n); } returnStr.append("]},"); }else{ returnStr.append("{id:"); returnStr.append(node.getId()); returnStr.append(",text:'"); returnStr.append(node.getText()); returnStr.append("'"); returnStr.append(",leaf:true},"); } } public boolean hasChild(List list, jackyNode node){ //判断是否有子节点 return getChildList(list,node).size()>0?true:false; } public List getChildList(List list , jackyNode node){ //得到子节点列表 List li = new ArrayList(); Iterator it = list.iterator(); while(it.hasNext()){ jackyNode n = (jackyNode)it.next(); if(n.getParentId()==node.getId()){ li.add(n); } } return li; } public String modifyStr(String returnStr){//修饰一下才能满足Extjs的Json格式 return ("["+returnStr+"]").replaceAll(",]", "]"); } public static void main(String[] args) { jackytree r = new jackytree(); r.recursionFn(r.nodeList, new jackyNode(1,0,"根节点")); System.out.println(r.modifyStr(r.returnStr.toString())); } }?
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1 楼 xyang81 2011-04-08 学习了。。。。正在想怎么找出父节点下有哪些子节点。。。。