Tcp编程demo之三部曲

下面的demo的目的是通过代码来快速的了解tcp编程的步骤

1首先呢，对InetAddress类简单了解其作用

public static void main(String[] args) throws Exception {
InetAddress inet=InetAddress.getByName("www.baidu.com");
System.out.println(inet);//百度地址
System.out.println(inet.getHostName());//ip地址对应的域名
System.out.println(inet.getHostAddress());//获取IP地址
InetAddress inet1=InetAddress.getLocalHost();//本地地址
System.out.println(inet1);//获取本机的地址ip

}

下面的demo的目的是：客户端给服务端发送消息，然后服务端打印到控制台上

package com.henu.liulei;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;

import org.junit.Test;

public class TestTcp1 {
public static void main(String[] args) {

}
@Test
public void client() {
Socket socket=null;
OutputStream os=null;
try {
socket=new Socket(InetAddress.getByName("127.0.0.1"),9090);
os=socket.getOutputStream();
os.write("我是客户端".getBytes());
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally {

try {
if(os!=null) {
os.close();
}
if(socket!=null) {
socket.close();
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
@Test
public void server() {
try {
ServerSocket socket=new ServerSocket(9090);
Socket socket1=socket.accept();
InputStream is=socket1.getInputStream();
byte[]b=new byte[20];
int len;
while((len=is.read(b))!=-1) {
String str=new String(b,0,len);
System.out.println(str);
}
is.close();
socket1.close();
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}
}

下面的demo的目的是客户端给服务端发送消息，然后服务端打印到控制台上，同时给客户端反馈消息

package com.henu.liulei;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;

import org.junit.Test;

public class TestTcp2 {

@Test
public void client() {
Socket socket=null;
OutputStream os=null;
try {
socket=new Socket(InetAddress.getByName("127.0.0.1"),9090);
os=socket.getOutputStream();
os.write("我是客户端".getBytes());
socket.shutdownOutput();//执行此方法告诉服务端表示已经发送完了
InputStream is=socket.getInputStream();
byte[]b=new byte[20];
int len;
while((len=is.read(b))!=-1) {
String str=new String(b,0,len);
System.out.println(str);
}
is.close();
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally {

try {
if(os!=null) {
os.close();
}
if(socket!=null) {
socket.close();
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
@Test
public void server() {
try {
ServerSocket socket=new ServerSocket(9090);
Socket socket1=socket.accept();
InputStream is=socket1.getInputStream();
byte[]b=new byte[20];
int len;
while((len=is.read(b))!=-1) {
String str=new String(b,0,len);
System.out.println(str);
}
OutputStream os=socket1.getOutputStream();
os.write("收到".getBytes());
os.close();
is.close();
socket1.close();
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}
}

最后一个demo的目的是从客户端发送给服务端，服务端接受并保存在本地，然后发消息给客户端表示接收到

package com.henu.liulei;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;

import org.junit.Test;

public class TestTcp3 {
@Test
public void client()
{
try {
//1:创建socket对象，
Socket socket=new Socket(InetAddress.getByName("127.0.0.1"),9090);
socket.setSoTimeout(10000);
//从本地获取一个文件，发送给服务端
OutputStream os=socket.getOutputStream();
FileInputStream fis=new FileInputStream(new File("C:/aaaaa.jpg"));
byte []b=new byte[1024];
int len;
while((len=fis.read(b))!=-1) {
os.write(b,0,len);
}
socket.shutdownOutput();
//接受来自服务端的信息
InputStream is= socket.getInputStream();
byte []b1=new byte[1024];
int len1;
while((len1 = is.read(b1))!=-1)
{
String str=new String(b1,0 , len1);
System.out.println(str);
}
//关闭相应的流
is.close();
fis.close();
os.close();
socket.close();
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}
@Test
public void server()
{
try {
//1创建一个serversocket对象
ServerSocket ss=new ServerSocket(9090);
//2:调用accept方法，返回一个socket对象
while(true) {
Socket s=ss.accept();
//把接受到的信息保存在本地
InputStream is=s.getInputStream();
FileOutputStream fos=new FileOutputStream(new File("C:/bbbbb.jpg"));
byte []b=new byte[1024];
int len ;
while((len=is.read(b))!=-1) {
fos.write(b, 0, len);
}
//发送“接收成功”的消息反馈给客户端
OutputStream os=s.getOutputStream();
os.write("你发送成功,已经接受".getBytes());
//关闭流
os.close();
fos.close();
is.close();
s.close();
}
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

}