Flex 对Java端返回Collection的处理方法
将Flex与Spring集成后（BlazeDS 与Spring集成指南 ），第一个面临的问题就是：对于Java端返回的各种Java类型的对象，Flex中能否有相应的数据类型来映射。
处理，尤其是List、Set、Map及POJO对象值。
在 BlazeDS 与Spring集成指南 例子的基础上，调整相关的测试代码如下：
1 1、Java端 2 1.1、com.yeeach.HelloWorldService 3 package com.yeeach; 4 5 import java.util.ArrayList; 6 import java.util.HashMap; 7 import java.util.HashSet; 8 import java.util.List; 9 import java.util.Map; 10 import java.util.Set; 11 12 public class HelloWorldService { 13 public String hello(String var1) { 14 return "hello " + var1; 15 } 16 public String world(String var1) { 17 return "world " + var1; 18 } 19 public Map<String,List<String>> getMap() { 20 ArrayList<String> list1=new ArrayList<String>(); 21 list1.add("value11"); 22 list1.add("value12"); 23 list1.add("value13"); 24 ArrayList<String> list2=new ArrayList<String>(); 25 list2.add("value21"); 26 list2.add("value22"); 27 list2.add("value23"); 28 ArrayList<String> list3=new ArrayList<String>(); 29 list3.add("value31"); 30 list3.add("value32"); 31 list3.add("value33"); 32 HashMap<String,List<String>> map=new HashMap<String,List<String>>(); 33 map.put("key1", list1); 34 map.put("key2", list2); 35 map.put("key3", list3); 36 return map; 37 } 38 public ArrayList<Person> getList() { 39 ArrayList <Person> list=new ArrayList<Person>(); 40 Person p1=new Person(); 41 p1.setName("name1"); 42 p1.setPass("pass1"); 43 Person p2=new Person(); 44 p2.setName("name2"); 45 p2.setPass("pass2"); 46 Person p3=new Person(); 47 p3.setName("name3"); 48 p3.setPass("pass3"); 49 list.add(p1); 50 list.add(p2); 51 list.add(p3); 52 return list; 53 } 54 public Set<Person> getSet() { 55 HashSet<Person> set=new HashSet<Person>(); 56 Person p1=new Person(); 57 p1.setName("name1"); 58 p1.setPass("pass1"); 59 Person p2=new Person(); 60 p2.setName("name2"); 61 p2.setPass("pass2"); 62 Person p3=new Person(); 63 p3.setName("name3"); 64 p3.setPass("pass3"); 65 set.add(p1); 66 set.add(p2); 67 set.add(p3); 68 return set; 69 } 70 } 71 72 1.2、com.yeeach.Person 73 package com.yeeach; 74 75 public class Person { 76 77 public String getName() { 78 return name; 79 } 80 public void setName(String name) { 81 this.name = name; 82 } 83 public String getPass() { 84 return pass; 85 } 86 public void setPass(String pass) { 87 this.pass = pass; 88 } 89 private String name; 90 private String pass; 91 92 }
2、Flex 端
2.1、helloworld.mxml
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
layout="vertical">
<mx:RemoteObject destination="test1"
id="test1">
<mx:method name="hello"
result="sayHelloResult(event)"/>
<mx:method name="world"
result="sayWorldResult(event)"/>
<mx:method name="getMap"
result="getMapResult(event)"/>
<mx:method name="getList"
result="getListResult(event)"/>
<mx:method name="getSet"
result="getSetResult(event)"/>
</mx:RemoteObject>
<mx:HBox>
<mx:Label text="输入："/>
<mx:TextInput id="inputStr"/>
<mx:Button label="say hello"
click="sayHello(event);"/>
<mx:Button label="say world"
click="sayWorld(event);"/>
<mx:Button label="get map"
click="test1.getMap()"/>
<mx:Button label="get list"
click="test1.getList()"/>
<mx:Button label="get set"
click="test1.getSet()"/>
</mx:HBox>
<mx:HBox>
<mx:Label text="结果："/>
<mx:TextArea id="result"/>
</mx:HBox>
<mx:Script>
<![CDATA[
import mx.collections.ArrayCollection;
import mx.rpc.events.FaultEvent;
import mx.controls.Alert;
import mx.rpc.events.ResultEvent;
import com.yeeach.Person;
[Bindable]
public var person:Person;
[Bindable]
public var map:ArrayCollection=null;
function sayHello(event:Event):void
{
var inputVar:String=inputStr.text;
test1.hello(inputVar);
}
function sayWorld(event:Event):void
{
var inputVar:String=inputStr.text;
test1.world(inputVar);
}
private function sayHelloResult(event:ResultEvent):void
{
result.text=event.result.toString();
Alert.show(event.result.toString(), "返回结果");
}
private function sayWorldResult(event:ResultEvent):void
{
result.text=event.result.toString();
Alert.show(event.result.toString(), "返回结果");
}
private function getMapResult(event:ResultEvent):void
{
for (var key:String in event.result)
{
var list:ArrayCollection=event.result[key] as ArrayCollection;
for (var key1:Object in list)
{
Alert.show("map item key is: " + key + " value is: " + key1);
}
}
}
private function getList():void
{
test1.getList();
}
private function getListResult(event:ResultEvent):void
{
var ac:ArrayCollection=event.result as ArrayCollection;
for (var i:int=0; i < ac.length; i++)
{
var p1:Person=ac.getItemAt(i) as Person;
Alert.show("list item name is: " + p1.name+" \n another usage : "+ac.getItemAt(i).name);
}
}
private function getSet():void
{
test1.getSet();
}
private function getSetResult(event:ResultEvent):void
{
var ac:ArrayCollection=event.result as ArrayCollection;
for (var i:int=0; i < ac.length; i++)
{
var p1:Person=ac.getItemAt(i) as Person;
Alert.show("set item name is: " + p1.name);
}
}
]]>
</mx:Script>
</mx:Application>
2.2、com.yeeach.Person.as
package com.yeeach
{
[Bindable]
[RemoteClass(alias="com.yeeach.Person")]
public class Person
{
public var name:String;
public var pass:String;
}
}
1、JavaBean从Java端返回给Flex，可以通过Flex的Meta Tag [RemoteClass (alias=” “)]来标识服务器端对应的Java的类（一般为POJO对象）。
注意位置，是在class声明前。
2、Java Collection返回给Flex，都可以通过转化为mx.collections.ArrayCollection来进行处理。
3、Flex对于服务器端返回的java其他类型的处理，相对简单，可以参考
http://livedocs.adobe.com/flex/3/html/help.html?content=data_access_4.html