浅析java网络编程

         Socket简称套接字，用于实现网络上客户和服务器之间的连接，也就是说网络上两个或两个以上通信的进程间总有一个连接，这个连接的端点称为套接字，套接字是比较低层次上的通信，不同操作系统对Scoket有不同的支持方式，不同的开发工具，对Socket的实现也均不相同，而且Scoket在TCP与UDP两大协议族系中有各自的工作方式。

 

           网络中互相通信的两端，其中提供服务的一端叫服务器，而请求服务的一端叫客户机。Scoket通常用来实现Client/Server设计过程，所谓Client/Server是指通信双方一方作为服务器（Server）等待客户（Client）提出请求并予以响应。客户则在需要服务时向服务器提出申请。服务器监听网络端口，一旦有客户请求，就会启动一个服务进程来响应客户，同时继续监听服务端口，使其他客户的请求也能及时得到处理。一般连接过程是：Server端监听某个端口（port）是否有连接请求，Client端向Server端发出连接（Connect）请求，Server端向Client端发出接受（Accept）消息，一个连接就建立起来了。Server端和Client端都可以通过Send，Write等方法与对方通信。

        在java中实现Scoket通讯：

        首先在服务器端创建ServerSocket类对象，来创建服务器对象，其格式如下：

        ServerSocket 服务器对象名 = new ServerSocket（端口号）；

通过调用accept（）方法来创建一个Scoket对象，其格式如下：

        Scoket 对象名 = 服务器对象名.accept（）；

服务器端可以用利用这个Scoket对象与客户端进行通讯，通过Scoket对象拿到输入输出流。在所有通信结束后，关闭输入输出流，再关闭Scoket。

 

        服务器和客户端属于两个不同项目

        以下是服务器类代码的实现：（MyServer类和ServerThread类在同一个项目包中）

 

 

import java.io.IOException;

import java.net.ServerSocket;

import java.net.Socket;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Map;

 

/**

 * 服务器类

 *

 */

public class MyServer {

//队列保存对象

public static ArrayList<ServerThread> list  = new ArrayList<ServerThread>();

 

//Map定义用户名密码集合

public static Map<String,String> userInfoMap = new HashMap<String,String>();

 

 

 

public static void main(String[] args) {

//初始化用户登录信息

for(int i=0;i<5;i++){

userInfoMap.put("user"+i, "pwd"+i);

}

MyServer ms = new MyServer();

ms.initServer(9090);

}

public void initServer(int port){

boolean flag = true;

try {

//创建服务器套接字对象，并给定端口号

ServerSocket server = new ServerSocket(port);

System.out.println("服务器创建成功，端口号为"+port+"，等待客户机连接");

 

while(flag){

//等待客户机连接服务器

Socket socket = server.accept();

System.out.println("客户机连接成功!");

//创建服务器线程对象

ServerThread st = new ServerThread(socket);

list.add(st);

st.start();

}

server.close();

} catch (IOException e) {

e.printStackTrace();

}

}

}

 

 

import java.io.BufferedReader;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.net.Socket;

 

import com.huaxin.client.CommonNet;

/**

 * 服务器线程对象

 */

public class ServerThread extends Thread{

public Socket socket;

public InputStream ins;

public OutputStream ous;

public ServerThread(Socket socket){

this.socket = socket;

}

public void run() {

try{

//拿到输入输出流

ins= socket.getInputStream();

ous =socket.getOutputStream();

 

//把字节流封装为字符流

InputStreamReader isReader = new InputStreamReader(ins);

BufferedReader read = new BufferedReader(isReader);

 

//发送消息给客户机

String msg = "欢迎连接服务器!\r\n";

CommonNet.sendMsg(ous,msg);

 

String user_msg = "请输入用户名：\r\n";

CommonNet.sendMsg(ous,user_msg);

//接收客户端发送过来的用户名

String username = read.readLine();

String user_pwd = "请输入密码：\r\n";

CommonNet.sendMsg(ous,user_pwd);

//接收客户端发送过来的用户名

String password = read.readLine();

 

//验证是否登录成功

if(MyServer.userInfoMap.containsKey(username)){

String pwd = MyServer.userInfoMap.get(username);

if(pwd.equals(password)){

CommonNet.sendMsg(ous,"true\r\n");

//循环读取消息

String value = "";

while(!"bye".equals(value)){

value = CommonNet.readMsg(ins);

System.out.println("客户机说："+value);

//把读取到的消息转发到其他客户

CommonNet.castMsg(this,username+"说："+value);

}

}else{

CommonNet.sendMsg(ous,"false\r\n");

}

}else{

CommonNet.sendMsg(ous,"false\r\n");

}

 

//关闭相关链接

ous.flush();

ous.close();

ins.close();

socket.close();

}catch(Exception e){

e.printStackTrace();

}

}

 

}

 

 

         下面是客户端类代码的实现：（MyClient类和CommonNet类属于同一项目的包中）

 

 

import java.io.BufferedReader;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.net.Socket;

import java.util.Scanner;

 

public class MyClient {

public static void main(String[] args) {

//连接服务器

try {

Socket client = new Socket("localhost",5656);

InputStream ins = client.getInputStream();

OutputStream ous = client.getOutputStream();

 

//把字节流封装为字符流

InputStreamReader isReader = new InputStreamReader(ins);

BufferedReader read = new BufferedReader(isReader);

//读取欢迎

String value = read.readLine();

System.out.println(value);

//读取请输入用户名

String value1 = read.readLine();

System.out.println(value1);

//发送消息

Scanner scan = new Scanner(System.in);

String scan_value = scan.nextLine();

CommonNet.sendMsg(ous, scan_value+"\r\n");

 

value1 = read.readLine();

System.out.println(value1);

scan_value = scan.nextLine();

CommonNet.sendMsg(ous, scan_value+"\r\n");

 

if("true".equals(read.readLine())){

System.out.println("登录成功");

}else{

System.out.println("登录失败");

}

 

ins.close();

ous.close();

client.close();

} catch (Exception e) {

e.printStackTrace();

}

}

 

}

 

 

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}

 

import java.io.InputStream;

import java.io.OutputStream;

import com.huaxin.server.MyServer;

import com.huaxin.server.ServerThread;

 

public class CommonNet {

/**

* 

* @param ous

* @param msg

* @throws Exception

*/

public static void sendMsg(OutputStream ous,String msg) throws Exception{

byte[] bytes = msg.getBytes();

ous.write(bytes);

}

/**

* 

* @param ins

* @return

* @throws Exception

*/

public static String readMsg(InputStream ins) throws Exception{

//接收客户机发送的消息

int readByte = ins.read();

String value = "";

StringBuffer sb = new StringBuffer();

//循环读取字节

while(readByte!=13){

sb.append((char)readByte);

readByte = ins.read();

}

//String.trim()去除字符串前后空格回车

value = sb.toString().trim();

return value;

}

/**

* 

* @param st

* @param value

* @throws Exception

*/

public static void castMsg(ServerThread st,String value) throws Exception{

for(int i=0;i<MyServer.list.size();i++){

OutputStream list_ous = MyServer.list.get(i).ous;

if(MyServer.list.get(i)!=st){

sendMsg(list_ous,value+"\r\n");

}

}

}

}