amf是Adobe独家开发的数据封装格式，Flash可以直接访问，由于它是基于二进制的数据传输，所以相对于xml SOAP、json、webService等基于字符串的数据格式，有数据体积小和效率高的特点。

amf目前有AMF0和AMF3两种格式，flash8以前版本只支持AMF0，flash9支持两种格式。AMF3比AMF0效率更高。

调试环境：

1、JDK 1.5

2、Resin 3.0

3、Flash CS3

4、flex-messaging-core.jar和flex-messaging-common.jar(这两个jar包文件可在Adobe的开源项目BlazeDS中找到)

Flash客户端代码：

/**

* ...

* @author Kinglong

* @version 0.1

*/

package project.test {

import flash.display.*;

import flash.events.*;

import flash.net.*;

import flash.utils.*;

public class TestAMF extends Sprite {

private var _loader:URLLoader;

public function TestAMF() {

trace("TestAMF");

_loader = new URLLoader();

_loader.dataFormat = URLLoaderDataFormat.BINARY;

_loader.addEventListener(Event.COMPLETE, loaderHandler);

_loader.addEventListener(SecurityErrorEvent.SECURITY_ERROR, loaderHandler);

_loader.addEventListener(IOErrorEvent.IO_ERROR, loaderHandler);

var request:URLRequest = new URLRequest("http://localhost:8080/ajax/servlet/test");

_loader.load(request);

}

private function loaderHandler(event:*):void {

trace(event.type);

switch(event.type) {

case Event.COMPLETE:

var start:Number=getTimer();

var byte:ByteArray = _loader.data as ByteArray;

byte.uncompress();

var obj:Object = byte.readObject();

var end:Number=getTimer();

trace("耗时：" + (end - start) + "毫秒");

trace(obj.fullName);

break;

}

}

}

}

/**
* ...
* @author Kinglong
* @version 0.1
*/
package project.test {
import flash.display.*;
import flash.events.*;
import flash.net.*;
import flash.utils.*;
public class TestAMF extends Sprite {
private var _loader:URLLoader;
public function TestAMF() {
trace("TestAMF");
_loader = new URLLoader();
_loader.dataFormat = URLLoaderDataFormat.BINARY;
_loader.addEventListener(Event.COMPLETE, loaderHandler);
_loader.addEventListener(SecurityErrorEvent.SECURITY_ERROR, loaderHandler);
_loader.addEventListener(IOErrorEvent.IO_ERROR, loaderHandler);
var request:URLRequest = new URLRequest("http://localhost:8080/ajax/servlet/test");
_loader.load(request);
}
private function loaderHandler(event:*):void {
trace(event.type);
switch(event.type) {
case Event.COMPLETE:
var start:Number=getTimer();
var byte:ByteArray = _loader.data as ByteArray;
byte.uncompress();
var obj:Object = byte.readObject();
var end:Number=getTimer();
trace("耗时：" + (end - start) + "毫秒");
trace(obj.fullName);
break;
}
}
}
}

Java服务端代码

import java.io.*;

import java.util.HashMap;

import java.util.Map;

import java.util.zip.*;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import flex.messaging.io.*;

import flex.messaging.io.amf.*;

public class TestServlet extends HttpServlet {

private static final long serialVersionUID = -1079073749217155506L;

private SerializationContext context = new SerializationContext();

public void doPost(HttpServletRequest request, HttpServletResponse response) throws

ServletException, IOException {

response.setContentType("application/x-gzip-compressed");

Amf3Output out = new Amf3Output(context);

DeflaterOutputStream stream = new DeflaterOutputStream(new DataOutputStream(response.getOutputStream()));

out.setOutputStream(stream);

Map map = new HashMap();

String[] arr = "1,2,3,4,5".split(",");

map.put("datas", arr);

map.put("userName","kinglong");

map.put("fullName", "金龙工作室");

map.put("domain", "klstudio.com");

out.writeObject(map);

stream.finish();

}

public void doGet(HttpServletRequest request, HttpServletResponse response) throws

ServletException, IOException {

doPost(request, response);

}

}

import java.io.*;
import java.util.HashMap;
import java.util.Map;
import java.util.zip.*;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import flex.messaging.io.*;
import flex.messaging.io.amf.*;
public class TestServlet extends HttpServlet {
private static final long serialVersionUID = -1079073749217155506L;
private SerializationContext context = new SerializationContext();
public void doPost(HttpServletRequest request, HttpServletResponse response) throws
ServletException, IOException {
response.setContentType("application/x-gzip-compressed");
Amf3Output out = new Amf3Output(context);
DeflaterOutputStream stream = new DeflaterOutputStream(new DataOutputStream(response.getOutputStream()));
out.setOutputStream(stream);
Map map = new HashMap();
String[] arr = "1,2,3,4,5".split(",");
map.put("datas", arr);
map.put("userName","kinglong");
map.put("fullName", "金龙工作室");
map.put("domain", "klstudio.com");
out.writeObject(map);
stream.finish();
}
public void doGet(HttpServletRequest request, HttpServletResponse response) throws
ServletException, IOException {
doPost(request, response);
}
}

因为AS3中的ByteArray支持zlib数据压缩和解压，所以我在服务端代码里增加数据压缩。

AMF3很适合Flash和后台服务端的数据交换，我写了这个范例，希望能给大家一参考。