<select id="cc" class="easyui-combotree" style="width:580px;" name="rempId"  data-options="required:true"></select>

<script>

$(function(){
$.ajax({
url:"departmentAction_getAllDep.action",
type:"post",
success:function(result){
//console.log(result);
$("#cc").combotree('loadData',b1(result));
}
});
$("#cc").combotree({
animate:true,
//選擇樹節點觸發事件  
   onSelect : function(node) { 
   n = node;
       //返回樹物件  
       var tree = $(this).tree;  
       //選中的節點是否為葉子節點,如果不是葉子節點,清除選中  
       var isLeaf = tree('isLeaf', node.target);  
       if (!isLeaf) {  
           //清除選中  
           $("#cc").combotree('clear');  
       }  
   }  
});
});

var tree = {
id:'',  
   text:'',  
   state:'',  
   checked:'',  
   iconCls:'',
   attributes:'',  
   children:''
}

function b1(result){
var t = [];
$.each(result,function(index,dept){
t[index] = b2(dept);
});
return t;
}

function b2(dept){
       var tree = new Object();
tree.id = dept.depId;  
   tree.text = dept.depName;  
   tree.state = 'closed';  
   tree.checked = 'false';
   if(dept.employees.length != 0){
   tree.children = b3(dept.employees);
   }else{
   tree.children = [];
   }
   return tree;
}

function b3(employees){  
   var easyTree = [];  
   $.each(employees,function(index,item){  
    easyTree[index] = b4(item);  
    });  
   return easyTree;  
} 
 
function b4(item){
var tree = new Object();
tree.id = item.empId;
tree.text = item.empName;
if(item.empSex == "男"){
tree.iconCls = 'icon-nan';
}else{
tree.iconCls = 'icon-female';
}
return tree;
}

</script>

department表中的dept_id作為employee表中有的外來鍵，生成的Department.java類中有Set<employee>物件。從後臺查詢部門表，得到List<Department>集合，通過struts2配置：

<action name="departmentAction_*" class="com.chinasoft.action.DepartmentAction" method="{1}">
<result name="getAllDep" type="json">
<param name="root">list</param>
</result>
</action>

轉成json格式後，傳到jsp頁面，在前臺頁面中處理json資料，動態生成下拉樹。