java Socket编程 客户端与服务器端在两个网里怎么实现连接 s = new Socket("127.0.0.1", 8880);这个IP怎么

s

=

new

socket("127001",

8880)

前面那个ip是服务器的地址，只要这个ip写正确了，服务器放在哪里，客户端都能连上去的。

1270。01最简单的解释就是本机地址，你用这个ip，访问的就是你自己。

你可以去服务器上查看一下网络地址，然后把1270。01换成服务器的ip。

写个简单点的服务器跟客服端就行了我写了个很简单的，只能在一个客户端跟一个服务器通信，在控制台输入下面这个是服务器import javaio;

import javanet;

import javautilScanner;public class Server

{

public static void main(String[] args)

{

try {

ServerSocket server=new ServerSocket(8888);//定义客户端的端口号

Socket client=serveraccept();//定义一个Socket对象

InputStream is=clientgetInputStream();//服务器接受信息输入流，也就是接受从服务器段发送过来的消息

BufferedReader br=new BufferedReader(new InputStreamReader(is));//用bufferedreader包装下输入流

OutputStream os=clientgetOutputStream();//这是用来给服务器发送消息的输出流

PrintStream ps=new PrintStream(os);

Scanner scanner=new Scanner(Systemin);//从键盘输入字符串

boolean flag=true;//定义一个死循环，让服务器不停的接受从客户端发送来的字符串

while(flag)

{

String s=brreadLine();//s是从客户端接受到得字符串

Systemoutprintln(s);

String s2=scannernextLine();//s2是写给客户端的字符串

psprintln(s2); //给客户端发送你写的东西

}

clientclose();

} catch (IOException e) {//try 跟catch你不用管，这是用来处理异常的，就是固定格式

eprintStackTrace();

}

}

} 下面是客户端import javaio;

import javanet;

import javautilScanner;public class Client

{ public static void main(String[] args)

{

try

{

Socket client=new Socket("192168----",8888);//IP地址是个字符串，端口号是个整数，这个端口号要跟前面你写的那个一样，还有IP地址，写你的机器的IP地址

InputStream is=clientgetInputStream();//这边的两个流跟上面服务器的差不多的作用

BufferedReader bf=new BufferedReader(new InputStreamReader(is));

OutputStream os=clientgetOutputStream();

PrintStream ps=new PrintStream(os);

Scanner scanner=new Scanner(Systemin);

boolean flag=true;

while(flag)//这句话可以让客户端不停的说话

{

String s2=scannernextLine();

psprintln(s2);

String s=bfreadLine();

Systemoutprintln(s); }

clientclose();

}

catch (UnknownHostException e)

{

eprintStackTrace();

}

catch (IOException e)

{

eprintStackTrace();

} }}

使用session机制，将参数动态的放在url后或使用cookies保存，将信息保存在url后或url链接后面。从服务器上再保存一份，就可以了。不过实现起来太复杂了。 暂不做介绍

现在有一个简单的办法就是可以在发送的消息前面加入一个随机值，当有新的请求到来的时候创建一个，然后保存起来。当客户端接收到这个随机值的时候，再回信息的时候将这个消息一并发给服务器。服务器可以这样判断，如果没有这个消息值的话就认为是一个新的用户，并为其创建一个消息。如果带有这消息的话，就是已经链接过的。这样就可以保持链接状态了。

import javaio;

import javanet;

import javautil;

public class ChatServer {

boolean started = false;

ServerSocket ss = null;

List<Client> clients = new ArrayList<Client>();//创建一个线程数组，这样每连接一个客户端就开启一个线程管理

public static void main(String[] args) {

new ChatServer()start();

}

public void start() {

try {

ss = new ServerSocket(8888);//服务器端监听8888号端口，如果有客户端向这个端口发起请求就可以被服务器端监听到

started = true;

} catch (BindException e) {

Systemoutprintln("端口使用中");

Systemoutprintln("请关掉相关程序并重新运行服务器！");

Systemexit(0);

} catch (IOException e) {

eprintStackTrace();

}

try {

while(started) {

Socket s = ssaccept();//服务器等待客户端的连接

Client c = new Client(s);//如果有客户端发出请求，把s传给Client

Systemoutprintln("a client connected!");

new Thread(c)start();//启动一个新进程，客户端与服务端建立通信

clientsadd(c);//

}

} catch (IOException e) {

eprintStackTrace();

} finally {

try {

ssclose();

} catch (IOException e) {

eprintStackTrace();

}

}

}

}

class Client implements Runnable {

private Socket s;

private DataInputStream dis = null;

private DataOutputStream dos = null;

private boolean bConnected = false;

public Client(Socket s) {

thiss = s;

try {

dis = new DataInputStream(sgetInputStream());//建立通信后，获得输入流

dos = new DataOutputStream(sgetOutputStream());//获得输出流

bConnected = true;

} catch (IOException e) {

eprintStackTrace();

}

}

public void send(String str) {

try {

doswriteUTF(str);//向流里面写入数据str

} catch (IOException e) {

eprintStackTrace();

}

}

public void run() {

try {

while(bConnected) {

String str = disreadUTF();//从流里面读取数据赋给str

Systemoutprintln(str);

for(int i=0; i<new ChatServer()clientssize(); i++) {

Client c = new ChatServer()clientsget(i);

csend(str);

}

}

} catch (EOFException e) {

Systemoutprintln("Client closed!");

} catch (IOException e) {

eprintStackTrace();

} finally {

try {

if(dis != null) disclose();

if(dos != null) dosclose();

if(s != null) {

sclose();

//s = null;

}

} catch (IOException e1) {

e1printStackTrace();

}

}

}

}

主要就是这些，客户端的程序不完整，而且跟服务端差不多，你对照着书看 应该能看懂

程序分Server和Client

服务器端打开侦听的端口，一有客户端连接就创建两个新的线程来负责这个连接

一个负责客户端发送的信息(ClientMsgCollectThread 类)，

另一个负责通过该Socket发送数据（ServerMsgSendThread ）

Serverjava代码如下:

/

创建日期 2009-3-7

TODO 要更改此生成的文件的模板，请转至

窗口 － 首选项 － Java － 代码样式 － 代码模板

/

package faueMutiUser;

import javaioBufferedReader;

import javaioIOException;

import javaioInputStreamReader;

import javaioPrintWriter;

import javanetServerSocket;

import javanetSocket;

/

服务器端

@author Faue

/

public class Server extends ServerSocket {

private static final int SERVER_PORT = 10000;

/

构造方法，用于实现连接的监听

@throws IOException

/

public Server() throws IOException {

super(SERVER_PORT);

try {

while (true) {

Socket socket = superaccept();

new Thread(new ClientMsgCollectThread(socket), "getAndShow"

+ socketgetPort())start();

new Thread(new ServerMsgSendThread(socket), "send"

+ socketgetPort())start();

}

} catch (IOException e) {

eprintStackTrace();

}

}

public static void main(String[] args) throws IOException {

new Server();

}

/

该类用于创建接收客户端发来的信息并显示的线程

@author Faue

@version 100

/

class ClientMsgCollectThread implements Runnable {

private Socket client;

private BufferedReader in;

private StringBuffer inputStringBuffer = new StringBuffer("Hello");

/

得到Socket的输入流

@param s

@throws IOException

/

public ClientMsgCollectThread(Socket s) throws IOException {

client = s;

in = new BufferedReader(new InputStreamReader(client

getInputStream(), "GBK"));

}

public void run() {

try {

while (!clientisClosed()) {

inputStringBufferdelete(0, inputStringBufferlength());

inputStringBufferappend(inreadLine());

Systemoutprintln(getMsg(inputStringBuffertoString()));

}

} catch (IOException e) {

//eprintStackTrace();

Systemoutprintln(clienttoString() + " is closed!");

}

}

/

构造显示的字符串

@param line

@return

/

private String getMsg(String line) {

return clienttoString() + " says:" + line;

}

}

/

该类用于创建发送数据的线程

@author Faue

@version 100

/

class ServerMsgSendThread implements Runnable {

private Socket client;

private PrintWriter out;

private BufferedReader keyboardInput;

private StringBuffer outputStringBuffer = new StringBuffer("Hello");

/

得到键盘的输入流

@param s

@throws IOException

/

public ServerMsgSendThread(Socket s) throws IOException {

client = s;

out = new PrintWriter(clientgetOutputStream(), true);

keyboardInput = new BufferedReader(new InputStreamReader(Systemin));

}

public void run() {

try {

while (!clientisClosed()) {

outputStringBufferdelete(0, outputStringBufferlength());

outputStringBufferappend(keyboardInputreadLine());

outprintln(outputStringBuffertoString());

}

} catch (IOException e) {

//eprintStackTrace();

Systemoutprintln(clienttoString() + " is closed!");

}

}

}

}

客户端：

实现基于IP地址的连接，连接后也创建两个线程来实现信息的发送和接收

/

创建日期 2009-3-7

/

package faueMutiUser;

import javaioBufferedReader;

import javaioIOException;

import javaioInputStreamReader;

import javaioPrintWriter;

import javanetSocket;

/

客户端

@author Faue

/

public class Client {

private Socket mySocket;

/

创建线程的构造方法

@param IP

@throws IOException

/

public Client(String IP) throws IOException {

try {

mySocket = new Socket(IP, 10000);

new Thread(new ServerMsgCollectThread(mySocket), "getAndShow"

+ mySocketgetPort())start();

new Thread(new ClientMsgSendThread(mySocket), "send"

+ mySocketgetPort())start();

} catch (IOException e) {

//eprintStackTrace();

Systemoutprintln("ServerIP:" + IP

+ " port:10000 can not be Connected");

}

}

public static void main(String[] args) throws IOException {

try {

new Client(args[0]);

} catch (Exception e) {

Systemoutprintln("输入的IP地址错误");

}

}

/

该类用于创建接收服务端发来的信息并显示的线程

@author Faue

@version 100

/

class ServerMsgCollectThread implements Runnable {

private Socket client;

private BufferedReader in;

private StringBuffer inputStringBuffer = new StringBuffer("Hello");

/

得到Socket的输入流

@param s

@throws IOException

/

public ServerMsgCollectThread(Socket s) throws IOException {

client = s;

in = new BufferedReader(new InputStreamReader(client

getInputStream(), "GBK"));

}

public void run() {

try {

while (!clientisClosed()) {

inputStringBufferdelete(0, inputStringBufferlength());

inputStringBufferappend(inreadLine());

Systemoutprintln(getMsg(inputStringBuffertoString()));

}

} catch (IOException e) {

//eprintStackTrace();

Systemoutprintln(clienttoString() + " is closed!");

Systemexit(0);

}

}

/

构造输入字符串

@param line

@return

/

private String getMsg(String line) {

return clienttoString() + " says:" + line;

}

}

/

该类用于创建发送数据的线程

@author Faue

@version 100

/

class ClientMsgSendThread implements Runnable {

private Socket client;

private PrintWriter out;

private BufferedReader keyboardInput;

private StringBuffer outputStringBuffer = new StringBuffer("Hello");

/

得到键盘的输入流

@param s

@throws IOException

/

public ClientMsgSendThread(Socket s) throws IOException {

client = s;

out = new PrintWriter(clientgetOutputStream(), true);

keyboardInput = new BufferedReader(new InputStreamReader(Systemin));

}

public void run() {

try {

while (!clientisClosed()) {

outputStringBufferdelete(0, outputStringBufferlength());

outputStringBufferappend(keyboardInputreadLine());

outprintln(outputStringBuffertoString());

}

outprintln("--- See you, bye! ---");

} catch (IOException e) {

//eprintStackTrace();

Systemoutprintln(clienttoString() + " is closed!");

Systemexit(0);

}

}

}

}

如果对您有帮助，请记得采纳为满意答案，谢谢！祝您生活愉快！

vaela

PrintWriter out = new PrintWriter(sgetOutputStream());

outwrite("你好!");

替换成

PrintStream out = new PrintStream(sgetOutputStream());

outprint("你好!");