Java 基于TCP_IP协议的网络编程

网络编程TCP_IP Socket ServerSocket

TCP编程：Socket ServerSocket

下面是三个情况下的网络编程TCP_IP：

1.客户端发送内容给服务端，服务端将内容打印到控制台上。

2.客户端发送内容给服务端，服务端给予反馈。

3.从客户端发送文件给服务端，服务端保存到本地。并返回“发送成功”给客户端。并关闭相应的连接。

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 org.junit.Test;

//TCP编程例一：客户端给服务端发送信息，服务端输出信息到控制台
//网络编程实际上就是Socket的编程
public class TestTCP1 {
// 客户端
@Test
public void client() {
Socket socket = null;
OutputStream os = null;
try {
//1.创建一个Socket的对象，通过构造器指明服务端的ip地址以及其接受程序的端口号
socket = new Socket(InetAddress.getByName("127.0.0.1"), 9090);
//2.getOutputStream()，发送数据，方法返回OutputStream的对象
os = socket.getOutputStream();
//3.具体的输出过程
os.write("我是客户端~".getBytes());
} catch (IOException e) {
e.printStackTrace();
} finally {
//4.关闭相应的流
if (os != null) {
try {
os.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}

}
}

}

// 服务端
@Test
public void server() {
ServerSocket ss = null;
Socket s = null;
InputStream is = null;
try {
//1.创建一个ServerSocket的对象，通过构造器指明自身的对象
ss = new ServerSocket(9090);
//2.调用其accept()地方法，返回一个Socket的对象
s = ss.accept();
//3.调用Socket的getInputStream()方法，获取一个从客户端发送过来的输入流
is = s.getInputStream();
//4.对获取到的流进行的操作
byte[] b = new byte[20];
int len;
while ((len = is.read(b)) != -1) {
String str = new String(b, 0, len);
System.out.println(str);

}
System.out.println("收到来自于" + s.getInetAddress().getHostAddress());
} catch (IOException e) {
e.printStackTrace();
} finally {
//5.关闭相应的Socket、SocketServer的对象
if (is != null) {
try {
is.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (is != null) {
try {
s.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (is != null) {
try {
ss.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

}
}

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import org.junit.Test;

//TCP编程例二：客户端给服务端发送信息，服务端将信息打印到控制台，同时发送“已收到信息”给服务端

public class TestTCP2 {
// 客户端
@Test
public void client() {
Socket socket = null;
OutputStream os = null;
InputStream is = null;
try {
socket = new Socket("127.0.0.1", 8989);
os = socket.getOutputStream();
os.write("我是客户端".getBytes());

//shutdownOutput()显式地告诉服务端发送完毕
socket.shutdownOutput();
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);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (is != null) {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}

}
if (os != null) {
try {
os.close();
} catch (IOException e) {
e.printStackTrace();
}

}
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}

}
}

}

// 服务端
@Test
public void server() {
ServerSocket ss = null;
Socket s = null;
InputStream is = null;
OutputStream os = null;
try {
ss = new ServerSocket(8989);
s = ss.accept();
is = s.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);
}

os = s.getOutputStream();
os.write("我已收到你的信息".getBytes());
} catch (IOException e) {
e.printStackTrace();
} finally {

if (os != null) {
try {
os.close();
} catch (IOException e) {
e.printStackTrace();
}

}
if (is != null) {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}

}
if (s != null) {
try {
s.close();
} catch (IOException e) {
e.printStackTrace();
}

}
if (ss != null) {
try {
ss.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}

}

}

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;

//TCP编程例三

//3.从客户端发送文件给服务端，服务端保存到本地。

//并返回“发送成功”给客户端。并关闭相应的连接

public class TestTCP3 {

@Test

public void client() {

// 1.创建Socket对象

Socket socket = null;

// 2.从本地获取一个文件发送服务器

OutputStream os = null;

FileInputStream fis = null;

// 3.接收来自服务器的信息

InputStream is = null;

try {

socket = new Socket(InetAddress.getByName(“127.0.0.1”), 8888);

os = socket.getOutputStream();

fis = new FileInputStream(new File("1.jpg"));
byte[] b = new byte[1024];
int len;
while ((len = fis.read(b)) != -1) {
os.write(b, 0, len);
}
socket.shutdownOutput();

is = socket.getInputStream();
byte[] b1 = new byte[1024];
int len1;
while ((len = is.read(b1)) != -1) {
String str = new String(b1);
System.out.println(str);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
// 4.关闭相应的流和Socket对象
if (is != null) {
try {
is.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (os != null) {
try {
os.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (fis != null) {
try {
fis.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

}

}

@Test
public void server() {
// 1.创建一个ServerSocket对象
ServerSocket ss = null;
// 2.调用accept()方法，返回一个Socket()的对象
Socket s = null;
// 3.将从客户端发送来的信息保存在本地
InputStream is = null;
FileOutputStream fos = null;
// 4.发送反馈信息
OutputStream os = null;
try {
ss = new ServerSocket(8888);
s = ss.accept();
is = s.getInputStream();

fos = new FileOutputStream(new File("4.jpg"));

byte[] b = new byte[1024];
int len;
while ((len = is.read(b)) != -1) {
fos.write(b, 0, len);
}
System.out.println("收到来自于" + s.getInetAddress().getHostName());
os = s.getOutputStream();
os.write("我已收到图片".getBytes());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {

if (os != null) {
try {
os.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (fos != null) {
try {
fos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (is != null) {
try {
is.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (s != null) {
try {
s.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (ss != null) {
try {
ss.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

}

}

}