treePanel json javaºǫ́

 function createTreeMenu(){//´´½¨Ò»¸öÊ÷µÄÃæ°å
 var treeMenu = new Ext.tree.TreePanel({
  lines : true,
  minSize : 150,
  border : false,
  root : new Ext.tree.AsyncTreeNode({text : 'root'}),
  loader : new Ext.tree.TreeLoader({dataUrl:'/extDemo/getData?action=treeMenu'})
 });
 
 var win = new Ext.Window({
  width : 600,
  height : 400,
  items : [treeMenu]
 });
 treeMenu.expandAll();
 win.show();
}
loaderÖеÄdataurl¶ÔÓ¦servletÖе÷ÓÃÒ»¸öÉú³ÉJsonµÄ·½·¨ÈçÏ£º
private String getTreeMenu(){
  List<Menu> list = new ArrayList<Menu>();
  
  for (int i = 0; i < 3; i++){
   Menu menu = new Menu();
   menu.setUrl(null);
   menu.setId("id_" + i);
   menu.setText("²Ëµ¥" + i);
   menu.setLeaf(false);
   for (int j = 0; j < 3; j++){
    Menu subMenu = new Menu();
    subMenu.setUrl("/extDemo/getData");
    subMenu.setId(i + "" + j);
    subMenu.setText("×Ӳ˵¥" + j);
    subMenu.setLeaf(true);
    menu.appendChild(subMenu);
   }
   list.add(menu);
  }
  
  return JSONArray.fromObject(list).toString();
 }
getTreeMenuÖеÄMenu´úÂëÈçÏ£º
public class Menu {
//ÒÔÏÂ×ֶεÄÃû×ÖÒ»¶¨ÒªÊÇÕâÑù£¬ÒòΪËüÃÇÒª¸úextÖеÄtreeNodeµÄÊôÐÔ¶ÔÓ¦.
 private String id;
 private String text;
 private String url;
 private boolean leaf;
 
 private List<Menu> children = new ArrayList<Menu>();
 public void appendChild(Menu subMenu){
  this.children.add(subMenu);
 }
/**»¹ÓкܶàgetºÍset·½·¨
*/
 
}