【服務器端】
JDK1.6,“java.net”包對網絡編程提供了非常全面的支持,包括Socket
開發環境:Eclipse
【客戶端】
Flex4,”flash.net”包也提供了Socket的支持
開發環境:FlashBuilder4
我是用Java啟動一個ServerSocket作為服務器,Flex創建一個頁面,當點擊頁面上的按鈕時向Java服務器發送消息。
Flex客戶端輸入“阿里巴巴”再點擊按鈕:

Java控制臺:
Flex項目分為兩種:一種是普通的本地項目,也就是不依賴其它服務器;另一種是遠程服務器項目,這需要依賴其它語言的服務器容器。如果是普通的本地項目,Socket通信是非常容易的,但是如果是遠程項目,Socket通信需要考慮Flex安全沙箱問題,后面會詳細介紹。
編寫Socket Server代碼的步驟通常是:
①創建ServerSocket,定義服務端口號
②使用ServerSocket.accept()監聽socket請求,如果有請求會創建一個Socket對象
③通過socket.getInputStream()獲取客戶端的請求數據
④通過socket.getOutputStream()向客戶端返回數據
⑤通過socket.close()結束本次會話
按照上面的步驟,如果有多個客戶端向服務器發送請求的話,服務器只會處理第一個請求,其它請求會排隊等待,只有第一個請求執行socket.close的時候下一個客戶端請求才會運行。為了實現多客戶端并發請求,在第②步后面需要建立多線程。
廢話不多說,直接代碼說明。
首先創建一個SocketUtil類,用于創建ServerSocket和獲取Socket
- public class SocketUtil {
-
-
-
-
-
-
- public static ServerSocket getServerSocket(int port){
- ServerSocket server = null;
- try {
- server = new ServerSocket(port);
- System.out.println("------ServerSocket創建成功,Port:"+port);
- return server;
- } catch (IOException e) {
- if(server!=null && !server.isClosed()){
- try {
- server.close();
- } catch (IOException e1) {
- e1.printStackTrace();
- }
- }
- throw new RuntimeException("創建ServerSocket時發生異常,Port:"+port,e);
- }
- }
-
-
-
-
-
-
- public static Socket getSocket(ServerSocket server){
- Socket socket = null;
- try {
- socket = server.accept();
- System.out.println("------Socket連接成功,IP:"+socket.getInetAddress());
- return socket;
- } catch (IOException e) {
- if(socket!=null && !socket.isClosed()){
- try {
- socket.close();
- } catch (IOException e1) {
- e1.printStackTrace();
- }
- }
- throw new RuntimeException("創建Socket時發送異常",e);
- }
- }
-
- }
public class SocketUtil {
/**
* 創建ServerSocket
* @param port
* @return
*/
public static ServerSocket getServerSocket(int port){
ServerSocket server = null;
try {
server = new ServerSocket(port);
System.out.println("------ServerSocket創建成功,Port:"+port);
return server;
} catch (IOException e) {
if(server!=null && !server.isClosed()){
try {
server.close();
} catch (IOException e1) {
e1.printStackTrace();
}
}
throw new RuntimeException("創建ServerSocket時發生異常,Port:"+port,e);
}
}
/**
* 獲取Socket
* @param server
* @return
*/
public static Socket getSocket(ServerSocket server){
Socket socket = null;
try {
socket = server.accept();
System.out.println("------Socket連接成功,IP:"+socket.getInetAddress());
return socket;
} catch (IOException e) {
if(socket!=null && !socket.isClosed()){
try {
socket.close();
} catch (IOException e1) {
e1.printStackTrace();
}
}
throw new RuntimeException("創建Socket時發送異常",e);
}
}
}
然后創建一個帶多線程的類,用于服務器與客戶端的IO通信
- public class SocketThread implements Runnable {
- private Socket socket;
- private String encoding;
-
- public SocketThread(Socket socket,String encoding) {
- this.socket = socket;
- this.encoding = encoding;
- }
-
-
-
-
- @Override
- public void run() {
- try {
- BufferedReader br = new BufferedReader(new InputStreamReader(socket
- .getInputStream(), encoding));
- BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(
- socket.getOutputStream(), encoding));
-
- String getMsg;
- while ((getMsg = br.readLine()) != null && !"exit".equalsIgnoreCase(getMsg)) {
-
- System.out.println("From client message:" + getMsg);
- bw.append("你好[" + socket.getInetAddress() + "],服務器收到你的信息:"
- + getMsg + "\r\n");
- bw.flush();
- }
-
-
- br.close();
- bw.close();
- socket.close();
- System.out.println("當前Socket連接結束......");
- } catch (Exception e) {
- if(!socket.isClosed()){
- try {
- socket.close();
- } catch (IOException e1) {
- e1.printStackTrace();
- }
- }
- throw new RuntimeException("Socket線程類發送異常...",e);
- }
- }
- }
public class SocketThread implements Runnable {
private Socket socket;
private String encoding;
public SocketThread(Socket socket,String encoding) {
this.socket = socket;
this.encoding = encoding;
}
/**
* 與客戶端交互代碼
*/
@Override
public void run() {
try {
BufferedReader br = new BufferedReader(new InputStreamReader(socket
.getInputStream(), encoding));
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(
socket.getOutputStream(), encoding));
String getMsg;
while ((getMsg = br.readLine()) != null && !"exit".equalsIgnoreCase(getMsg)) {
// 客戶端未提出"exit"命令,則循環交流
System.out.println("From client message:" + getMsg);
bw.append("你好[" + socket.getInetAddress() + "],服務器收到你的信息:"
+ getMsg + "\r\n");
bw.flush();
}
//客戶端提出"exit"請求,關閉當前socket...
br.close();
bw.close();
socket.close();
System.out.println("當前Socket連接結束......");
} catch (Exception e) {
if(!socket.isClosed()){
try {
socket.close();
} catch (IOException e1) {
e1.printStackTrace();
}
}
throw new RuntimeException("Socket線程類發送異常...",e);
}
}
}
最后在Main函數中啟動Socket服務即可:
- public static void main(String[] args) {
- new SocketServer().startSocket();
- }
public static void main(String[] args) {
new SocketServer().startSocket();
}
Flex端創建Socket有兩種方式:
第一種通過connect方法連接Socket服務器:
- var socket:Socket = new Socket();
- socket.connect("localhost",10086);
var socket:Socket = new Socket();
socket.connect("localhost",10086);
第二種通過創建Socket實例時在構造函數中傳入服務器ip和端口號連接:
- socket = new Socket("localhost",10086);
socket = new Socket("localhost",10086);
Flex通過ByteArray傳送IO數據,這里有一點稍微注意一下在寫入的內容后面會加"\r\n"回車換行符,因為java端是通過BufferedReader.readLine的形式獲取一行數據,如果不換行服務器端IO就一直處于阻塞狀態:
-
- var message:ByteArray = new ByteArray();
-
- message.writeUTFBytes(txt_socket.text+"\r\n");
-
- socket.writeBytes(message);
//ByteArray存放數據
var message:ByteArray = new ByteArray();
//使用UTF形式防止中文亂碼
message.writeUTFBytes(txt_socket.text+"\r\n");
//數據寫入緩沖區
socket.writeBytes(message);
Flex有多種事件用于監聽Socket的狀態:
- Event.CONNECT:Socket與服務器成功連接時觸發的事件
- Event.CLOSE:Socket與服務器斷開連接時觸發的事件
- IOErrorEvent.IO_ERROR:Socket通信時發生IO錯誤時觸發的事件
- ProgressEvent.SOCKET_DATA:服務器返回數據時觸發的事件
Event.CONNECT:Socket與服務器成功連接時觸發的事件
Event.CLOSE:Socket與服務器斷開連接時觸發的事件
IOErrorEvent.IO_ERROR:Socket通信時發生IO錯誤時觸發的事件
ProgressEvent.SOCKET_DATA:服務器返回數據時觸發的事件
新建一個Flex普通項目,入口文件定義為index.mxml,在mxml文件中新建一個textinput文本框用于獲取用戶輸入的內容,button按鈕用戶發送內容到java socket服務器,一個label用戶顯示向前socket狀態,另一個label用于顯示從服務器返回的信息。 index.mxml代碼如下:
- <s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
- xmlns:s="library://ns.adobe.com/flex/spark"
- xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
-
- <fx:Script>
- <![CDATA[
-
-
- private var socket:Socket = null;
- protected function button1_clickHandler(event:MouseEvent):void
- {
- if(socket==null || !socket.connected){
- //連接服務器(ip,port)
- socket = new Socket("localhost",10086);
-
- //成功連接狀態事件
- socket.addEventListener(Event.CONNECT,function connFun(e:Event):void{
- l_status.text = "Connect to server success...";
- });
- //連接中斷事件
- socket.addEventListener(Event.CLOSE,function closeFun(e:Event):void{
- l_status.text = "Connect to server closed...";
- });
- //連接異常事件
- socket.addEventListener(IOErrorEvent.IO_ERROR,function closeFun(e:IOErrorEvent):void{
- l_status.text = "Connect exception ..."+e.toString();
- });
- //服務器信息事件
- socket.addEventListener(ProgressEvent.SOCKET_DATA,function dataFun(e:ProgressEvent):void{
- var getMsg:ByteArray = new ByteArray;
- socket.readBytes(getMsg);
- l_result.text = getMsg.toString();
- });
- }
-
- //ByteArray存放數據
- var message:ByteArray = new ByteArray();
- //使用UTF形式防止中文亂碼
- message.writeUTFBytes(txt_socket.text+"\r\n");
- //數據寫入緩沖區
- socket.writeBytes(message);
- //將緩沖區數據發送出去
- socket.flush();
- //清空文本框內容
- txt_socket.text = "";
- }
- ]]>
- </fx:Script>
-
- <fx:Declarations>
-
- </fx:Declarations>
- <s:Button x="156" y="56" label="按鈕" click="button1_clickHandler(event)"/>
- <s:TextInput x="20" y="56" id="txt_socket"/>
- <s:Label x="20" y="104" id="l_status"/>
- <s:Label x="234" y="65" id="l_result"/>
- </s:Application>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
<fx:Script>
<![CDATA[
private var socket:Socket = null;
protected function button1_clickHandler(event:MouseEvent):void
{
if(socket==null || !socket.connected){
//連接服務器(ip,port)
socket = new Socket("localhost",10086);
//成功連接狀態事件
socket.addEventListener(Event.CONNECT,function connFun(e:Event):void{
l_status.text = "Connect to server success...";
});
//連接中斷事件
socket.addEventListener(Event.CLOSE,function closeFun(e:Event):void{
l_status.text = "Connect to server closed...";
});
//連接異常事件
socket.addEventListener(IOErrorEvent.IO_ERROR,function closeFun(e:IOErrorEvent):void{
l_status.text = "Connect exception ..."+e.toString();
});
//服務器信息事件
socket.addEventListener(ProgressEvent.SOCKET_DATA,function dataFun(e:ProgressEvent):void{
var getMsg:ByteArray = new ByteArray;
socket.readBytes(getMsg);
l_result.text = getMsg.toString();
});
}
//ByteArray存放數據
var message:ByteArray = new ByteArray();
//使用UTF形式防止中文亂碼
message.writeUTFBytes(txt_socket.text+"\r\n");
//數據寫入緩沖區
socket.writeBytes(message);
//將緩沖區數據發送出去
socket.flush();
//清空文本框內容
txt_socket.text = "";
}
]]>
</fx:Script>
<fx:Declarations>
<!-- 將非可視元素(例如服務、值對象)放在此處 -->
</fx:Declarations>
<s:Button x="156" y="56" label="按鈕" click="button1_clickHandler(event)"/>
<s:TextInput x="20" y="56" id="txt_socket"/>
<s:Label x="20" y="104" id="l_status"/>
<s:Label x="234" y="65" id="l_result"/>
</s:Application>
代碼編寫完成后運行index.mxml文件,最后執行效果就如前面【實例效果】所示。
下面這段是從網上抄的:
----------------------------------------------------------------------------
在 Adobe Flash Player 升級到 9.0.124 后,由于安全策略更改,原來 Socket 或 XmlSocket 的應用里的 http 方式加載安全策略的手段不能繼續使用。更改如下:
1, 首先檢測目標服務器的 843 端口是否提供安全策略
2, 如果 1 沒有檢測到策略,則檢測 actionscript 是否使用了 Security.loadPolicyFile(xmlsocket://)手段提供安全策略,如果還沒檢測到,則使用第 3 步檢測
3, 檢測目標服務器目標端口是否提供安全策略。
在說具體處理方式前,我先描述一下 Flash Player 的驗證過程。在 Flex 程序發出 Socket 或 XmlSocket( 以下統稱為 Socket) 請求前, FlashPlayer 會先判斷是否為本地調用,如果不是。即用一個 Socket 去鏈接到你的服務端,三次握手成功后一方面發出字符串“ <policy-file-request/>\0 “另一方面監聽返回的安全策略。安全策略接收成功后, FlashPlayer 就斷開驗證的 Socket ,然后再運行程序本身的 Socket 。在整個 SWF 運行期間,無論你請求多少次,只要域相同, FlashPlayer 就只驗證一次。這里有兩個重點:
第一個是驗證的 Socket 和程序的 Socket 是兩個 Socket 。所以你在本地測試時,服務端監聽到 N 個 Socket 請求,但布置到服務端后,服務端會監聽到 N+1 個請求。
第二是驗證的 Socket 發送“ <policy-file-request/>\0 “請求和接收你的策略文件是沒有先后關系的,所以你沒必要接收完“ <policy-file-request/>\0 “后才發策略文件。我的做法是只要監聽到請求,就把策略字符串發過去。
-----------------------------------------------------------------------------------
那么簡單的說,如果Flex項目依賴其它語言的服務器的話(比如依賴J2EE服務器),在flex的socket客戶端向JavaSocket服務器發送請求之前,Flex會優先發送一個安全驗證消息,如果java服務器不返回驗證消息則當前socket通信失敗。
解決辦法有很多種,我在網上也看了很多,但是很多寫得有問題。
根據我多方調查,個人覺得這種方案比較靠譜:
在Java服務器端創建一個端口號為843的ServerSocket監聽Flex安全沙箱驗證消息,如果接收到<policy-file-request/>文件信息,則向客戶端返回XMl驗證內容:“<?xml version=\"1.0\"?><cross-domain-policy><site-control permitted-cross-domain-policies=\"all\"/><allow-access-from domain=\"*\" to-ports=\"*\"/></cross-domain-policy>\0”
具體代碼如下:
-
-
-
-
- public class PolicyThread implements Runnable {
- private final String policy_xml = "<policy-file-request/>";
- private final String cross_xml = "<?xml version=\"1.0\"?><cross-domain-policy><site-control permitted-cross-domain-policies=\"all\"/><allow-access-from domain=\"*\" to-ports=\"*\"/></cross-domain-policy>\0";
- private Socket socket;
-
- public PolicyThread(Socket socket){
- this.socket = socket;
- }
-
- @Override
- public void run() {
- try {
-
- BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
- PrintWriter pw = new PrintWriter(socket.getOutputStream());
- char[] by = new char[22];
- br.read(by, 0, 22);
- String s = new String(by);
- if(s.equals(policy_xml)){
- System.out.println("接收policy-file-request認證");
- pw.print(cross_xml);
- pw.flush();
- br.close();
- pw.close();
- socket.close();
- System.out.println("完成policy-file-request認證");
- }
- } catch (IOException e) {
- if(!socket.isClosed()){
- try {
- socket.close();
- } catch (IOException e1) {
- e1.printStackTrace();
- }
- }
- throw new RuntimeException("執行policy認證時發生異常",e);
- }
- }
-
- }
/**
* 處理與Flex認證的線程類
* @author Administrator
*/
public class PolicyThread implements Runnable {
private final String policy_xml = "<policy-file-request/>";
private final String cross_xml = "<?xml version=\"1.0\"?><cross-domain-policy><site-control permitted-cross-domain-policies=\"all\"/><allow-access-from domain=\"*\" to-ports=\"*\"/></cross-domain-policy>\0";
private Socket socket;
public PolicyThread(Socket socket){
this.socket = socket;
}
@Override
public void run() {
try {
//接收并發送Flex安全驗證請求
BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
PrintWriter pw = new PrintWriter(socket.getOutputStream());
char[] by = new char[22];
br.read(by, 0, 22);
String s = new String(by);
if(s.equals(policy_xml)){
System.out.println("接收policy-file-request認證");
pw.print(cross_xml);
pw.flush();
br.close();
pw.close();
socket.close();
System.out.println("完成policy-file-request認證");
}
} catch (IOException e) {
if(!socket.isClosed()){
try {
socket.close();
} catch (IOException e1) {
e1.printStackTrace();
}
}
throw new RuntimeException("執行policy認證時發生異常",e);
}
}
}
- public class PolicyServer implements Runnable{
-
- private final int policy_port = 843;
- private boolean status = true;
-
- private ServerSocket server = null;
- @Override
- public void run() {
-
- server = SocketUtil.getServerSocket(policy_port);
-
- while(status){
- Socket socket = SocketUtil.getSocket(server);
- new Thread(new PolicyThread(socket)).start();
- }
- }
-
-
-
-
-
- public void startPolicy(){
- new Thread(this).start();
- }
-
-
-
-
- public void stopPolicy(){
- status = false;
- if(server!=null && !server.isClosed()){
- try {
- server.close();
- } catch (IOException e) {
- e.printStackTrace();
- }
- }
- }
- }
public class PolicyServer implements Runnable{
private final int policy_port = 843;
private boolean status = true;
private ServerSocket server = null;
@Override
public void run() {
//創建安全驗證服務器
server = SocketUtil.getServerSocket(policy_port);
while(status){
Socket socket = SocketUtil.getSocket(server);
new Thread(new PolicyThread(socket)).start();
}
}
/**
* 啟動服務器
*/
public void startPolicy(){
new Thread(this).start();
}
/**
* 關閉服務器
*/
public void stopPolicy(){
status = false;
if(server!=null && !server.isClosed()){
try {
server.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
Flex客戶端向Java發送第一次Socket請求(例子里的端口號是10086)時,ServerSocket843端口會收到安全沙箱驗證,隨后server將正確的驗證消息返回給Flex客戶端,Flex認證成功后真正的10086端口Socket連結就已經搭建了,隨后雙方就可以暢通無阻通信了(一次會話只進行一次沙箱驗證)。
我通常比較喜歡創建一個servlet,在web.xml中配置容器啟動時運行servlet的init方法,這樣端口號為10086和843的serverSocket就會啟動:
- public class InitServers extends HttpServlet {
- private static final long serialVersionUID = 1L;
-
-
-
-
- public InitServers() {
- super();
- }
-
-
-
-
- public void init(ServletConfig config) throws ServletException {
- new PolicyServer().startPolicy();
- new SocketServer().startSocket();
- }
-
-
-
-
- protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
-
- }
-
-
-
-
- protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
-
- }
-
- }
public class InitServers extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public InitServers() {
super();
}
/**
* @see Servlet#init(ServletConfig)
*/
public void init(ServletConfig config) throws ServletException {
new PolicyServer().startPolicy();
new SocketServer().startSocket();
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
}
web.xml
- <servlet>
- <display-name>InitServers</display-name>
- <servlet-name>InitServers</servlet-name>
- <servlet-class>socket.InitServers</servlet-class>
- <load-on-startup>1</load-on-startup>
- </servlet>
<servlet>
<display-name>InitServers</display-name>
<servlet-name>InitServers</servlet-name>
<servlet-class>socket.InitServers</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
以上一個完整的Flex+Java的Socket通信就完成了。