网络通信

网络通信的第一个元素：IP地址。通过IP地址，唯一的定位互联网上一台 
 * 主机
 *InetAddress:位于java.net包下
 *1.InetAddress用来代表IP地址。一个InetAddress的对象就代表着一个IP
 *地址
 *2.如何创建InetAddress的对象：getName(String host)
 *3.getHostName()获取IP地址对应的域名。getHostAddress()获取IP地址
 *
 *
 *
 *
 */
/**
 * A类网络的IP地址范围为1.0.0.1－127.255.255.254； B类网络的IP地址范围为：128.1.0.1－191.255.255.254；
 * C类网络的IP地址范围为：192.0.1.1－223.255.255.254。
 * 
 * 
 */
public class TestInetAddress {
public static void main(String[] args) throws UnknownHostException {
// 创建一个InetAddress对象
InetAddress inet = InetAddress.getByName("www.beicai.com");
// inet = InetAddress.getByName("119.90.141.3");
System.out.println(inet);
System.out.println(inet.getHostName());
System.out.println(inet.getHostAddress());
System.out.println();
// 获取本机的IP
InetAddress inet1 = InetAddress.getLocalHost();
System.out.println(inet1);
System.out.println(inet1.getHostName());
System.out.println(inet1.getHostAddress());

}
}

public class TestInetAddress {public static void main(String[] args) throws UnknownHostException {// 创建一个InetAddress对象InetAddress inet = InetAddress.getByName("www.beicai.com");// inet = InetAddress.getByName("119.90.141.3");System.out.println(inet);System.out.println(inet.getHostName());System.out.println(inet.getHostAddress());System.out.println();// 获取本机的IPInetAddress inet1 = InetAddress.getLocalHost();System.out.println(inet1);System.out.println(inet1.getHostName());System.out.println(inet1.getHostAddress());}}

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编程例一：客户端给服务端发送信息。服务端输出信息到控制台上public class TestTCP {// 客户端@Testpublic void client() {Socket socket = null;OutputStream os = null;try {// 1.创建socket对象，通过构造器指明服务端的IP地址，及其// 接收的端口号socket = new Socket("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("你瞅啥？".getBytes());} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();} finally {if (os != null) {try {os.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}if (socket != null) {try {socket.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}}// 服务端@Testpublic 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端口号ss = new ServerSocket(9090);// 2.调用accept()方法，返回一个Socket的对象s = ss.accept();// 3.调用Socket对象的getInputStream()获取一个从客户端发送// 过来的输入流is = s.getInputStream();// 4.对获取的输入流进行操作byte[] b = new byte[20];int len;while ((len = is.read(b)) != -1) {String str = new String(b, 0, len);System.out.println(str);}} catch (IOException e) {e.printStackTrace();} finally {// TODO: handle finally clause// 5.关闭相应的流，Socket,ServerSocket的对象if (is != null) {try {is.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}if (s != null) {try {s.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}if (ss != null) {try {ss.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}}}

//客户端给服务端发送信息，服务端将信息打印到控制台上，同时发送回执
//给客户端
public class TestTCP2 {


// 客户端
@Test
public void client() {
Socket socket = null;
OutputStream os = null;
InputStream is = null;
try {
socket = new Socket("10.114.19.237", 8989);
os = socket.getOutputStream();
os.write("你瞅啥？".getBytes());
// shutdownOutput():显示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) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
if (is != null) {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (os != null) {
try {
os.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();
}
}
}


}


// 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("瞅你咋地！".getBytes());
} catch (IOException e) {
e.printStackTrace();
} finally {
// TODO: handle finally clause
if (os != null) {
try {
os.close();
} catch (IOException e) {
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();
}
}
}


}

}

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;


import org.junit.Test;
import java.io.InputStream;
import java.io.OutputStream;


//TCP编程例三：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
public class TestTCP3 {
// 客户端
@Test
public void client() {
// 1.创建Socket的对象
Socket socket = null;
// 2.从本地获取一个文件发送给服务端
OutputStream os = null;
FileInputStream fis = null;
// 3.接收来自于服务端的消息
InputStream is = null;
try {
socket = new Socket(InetAddress.getByName("127.0.0.1"), 9898);
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 ((len1 = is.read(b1)) != -1) {
String str = new String(b1, 0, len1);
System.out.println(str);
}
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} finally {


if (fis != null) {
try {
fis.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 (socket != null) {
try {
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// 4.关闭相应的流和服务端的消息
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();
}
}
}


// 服务端
@Test
public void server() {
// 1.创建一个ServerSocket的对象
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文件保存到本地
InputStream is = null;
FileOutputStream fos = null;
// 4.发送回执反馈给客户端
OutputStream os = null;
try {
ss = new ServerSocket(9898);


s = ss.accept();


is = s.getInputStream();
fos = new FileOutputStream(new File("2.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().getHostAddress() + "的文件");


os = s.getOutputStream();
os.write("头像上传成功".getBytes());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
// 5.关闭相应的流和Socket、ServerSocket的对象
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();
}
}
}
}
}