|
------<a href="http://www.itheima.com" target="blank">Java培训、Android培训、iOS培训、.Net培训</a>、期待与您交流! -------
一.IP地址
每个设备在网络中的唯一标识
每台网络终端在网络中都有一个独立的地址,我们在网络中传输数据就是使用这个地址。
ipconfig:查看本机IP
ping:测试连接
本地回路地址:127.0.0.1255.255.255.255是广播地址
IPv4:4个字节组成,4个0-255。大概42亿,30亿都在北美,亚洲4亿。2011年初已经用尽。
IPv6:8组,每组4个16进制数。
1a2b:0000:aaaa:0000:0000:0000:aabb:1f2f
1a2b::aaaa:0000:0000:0000:aabb:1f2f
1a2b:0000:aaaa::aabb:1f2f
1a2b:0000:aaaa::0000:aabb:1f2f
1a2b:0000:aaaa:0000::aabb:1f2f
二.端口号
每个程序在设备上的唯一标识
每个网络程序都需要绑定一个端口号,传输数据的时候除了确定发到哪台机器上,还要明确发到哪个程序。
端口号范围从0-65535
编写网络应用就需要绑定一个端口号,尽量使用1024以上的,1024以下的基本上都被系统程序占用了。
常用端口
mysql: 3306
oracle: 1521
web: 80
tomcat: 8080
QQ: 4000
feiQ: 2425
三.网络协议
为计算机网络中进行数据交换而建立的规则、标准或约定的集合。
UDP
面向无连接,数据不安全,速度快。不区分客户端与服务端。
TCP
面向连接(三次握手),数据安全,速度略低。分为客户端和服务端。
三次握手: 客户端先向服务端发起请求, 服务端响应请求, 传输数据
四.Socket
通信的两端都有Socket。
网络通信其实就是Socket间的通信。
数据在两个Socket间通过IO流传输。
Socket在应用程序中创建,通过一种绑定机制与驱动程序建立关系,告诉自己所对应的IP和port。
五.UDP传输
1.发送
创建DatagramSocket, 随机端口号
创建DatagramPacket, 指定数据, 长度, 地址, 端口
使用DatagramSocket发送DatagramPacket
关闭DatagramSocket
2.接收
创建DatagramSocket, 指定端口号
创建DatagramPacket, 指定数组, 长度
使用DatagramSocket接收DatagramPacket
关闭DatagramSocket
从DatagramPacket中获取数据
3.接收方获取ip和端口号
String ip =packet.getAddress().getHostAddress();
int port = packet.getPort();
- import java.io.IOException;
- import java.net.DatagramPacket;
- import java.net.DatagramSocket;
- import java.net.InetAddress;
- import java.net.SocketException;
- import java.util.Scanner;
-
- public class Demo2_Send {
-
-
-
-
-
-
-
- public static void main(String[] args) throws IOException {
-
- DatagramSocket socket = new DatagramSocket();
- Scanner sc = new Scanner(System.in);
- while (true) {
- String line = sc.nextLine();
- if("quit".equals(line))
- break;
- DatagramPacket packet =
- new DatagramPacket(line.getBytes(), line.getBytes().length,InetAddress.getByName("127.0.0.1"), 6666);
- socket.send(packet);
- }
- socket.close();
- }
-
- }
- import java.io.IOException;
- import java.net.DatagramPacket;
- import java.net.DatagramSocket;
- import java.net.SocketException;
-
- public class Demo2_Receive {
-
-
-
-
-
-
-
-
-
-
- public static void main(String[] args) throws IOException {
- DatagramSocket socket = new DatagramSocket(6666);
- DatagramPacket packet = new DatagramPacket(new byte[1024], 1024);
- while(true) {
- socket.receive(packet);
- byte[] arr = packet.getData();
- int len = packet.getLength();
- String ip = packet.getAddress().getHostAddress();
- System.out.println(ip + ":" + new String(arr,0,len));
- }
- }
-
- }
多线程
- import java.io.IOException;
- import java.net.DatagramPacket;
- import java.net.DatagramSocket;
- import java.net.InetAddress;
- import java.net.SocketException;
- import java.net.UnknownHostException;
- import java.util.Scanner;
-
- public class Demo3_MoreThread {
-
-
-
-
- public static void main(String[] args) {
- new Receive().start();
- new Send().start();
- }
-
- }
-
- class Receive extends Thread {
- public void run() {
- try {
- DatagramSocket socket = new DatagramSocket(6666);
- DatagramPacket packet = new DatagramPacket(new byte[1024], 1024);
- while(true) {
- socket.receive(packet);
- byte[] arr = packet.getData();
- int len = packet.getLength();
- String ip = packet.getAddress().getHostAddress();
- System.out.println(ip + ":" + new String(arr,0,len));
- }
- } catch (Exception e) {
-
- e.printStackTrace();
- }
- }
- }
-
- class Send extends Thread {
- public void run() {
- try {
- DatagramSocket socket = new DatagramSocket();
- Scanner sc = new Scanner(System.in);
- while (true) {
- String line = sc.nextLine();
- if("quit".equals(line))
- break;
- DatagramPacket packet =
- new DatagramPacket(line.getBytes(), line.getBytes().length,InetAddress.getByName("192.168.33.186"), 6666);
- socket.send(packet);
- }
- socket.close();
- } catch (Exception e) {
-
- e.printStackTrace();
- }
- }
- }
六.TCP传输
1.客户端
创建Socket连接服务端(指定ip地址,端口号)通过ip地址找对应的服务器
调用Socket的getInputStream()和getOutputStream()方法获取和服务端相连的IO流
输入流可以读取服务端输出流写出的数据
输出流可以写出数据到服务端的输入流
- import java.io.BufferedReader;
- import java.io.BufferedWriter;
- import java.io.IOException;
- import java.io.InputStream;
- import java.io.InputStreamReader;
- import java.io.OutputStream;
- import java.io.OutputStreamWriter;
- import java.io.PrintStream;
- import java.net.Socket;
- import java.net.UnknownHostException;
-
- public class Demo2_Client {
-
-
-
-
-
-
-
-
-
-
- public static void main(String[] args) throws Exception {
- Socket socket = new Socket("127.0.0.1", 12345);
-
-
-
-
-
-
-
-
-
- BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
-
- PrintStream ps = new PrintStream(socket.getOutputStream());
- System.out.println(br.readLine());
- ps.println("我要报名就业班");
- System.out.println(br.readLine())
- ps.println("不学了");
-
- socket.close();
- }
-
- }
2.服务端
创建ServerSocket(需要指定端口号)
调用ServerSocket的accept()方法接收一个客户端请求,得到一个Socket
调用Socket的getInputStream()和getOutputStream()方法获取和客户端相连的IO流
输入流可以读取客户端输出流写出的数据
输出流可以写出数据到客户端的输入流
- import java.io.BufferedReader;
- import java.io.BufferedWriter;
- import java.io.IOException;
- import java.io.InputStream;
- import java.io.InputStreamReader;
- import java.io.OutputStream;
- import java.io.OutputStreamWriter;
- import java.io.PrintStream;
- import java.net.ServerSocket;
- import java.net.Socket;
-
- public class Demo2_Server {
-
-
-
-
-
-
-
-
-
-
- public static void main(String[] args) throws Exception {
- ServerSocket server = new ServerSocket(54321);
- Socket socket = server.accept();
-
-
-
-
-
-
-
-
- BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
-
-
-
- PrintStream ps = new PrintStream(socket.getOutputStream());
- ps.println("欢迎咨询传智播客");
- System.out.println(br.readLine());
- ps.println("报满了,等下一期吧");
- System.out.println(br.readLine());
- server.close();
- socket.close();
- }
-
- }
创建多线程的服务端,可以不断的向服务端访问
- import java.io.BufferedReader;
- import java.io.IOException;
- import java.io.InputStreamReader;
- import java.io.PrintStream;
- import java.net.ServerSocket;
- import java.net.Socket;
-
- public class Demo3_MoreThread {
-
-
-
-
-
- public static void main(String[] args) throws IOException {
- ServerSocket server = new ServerSocket(12345);
- while(true) {
- final Socket socket = server.accept();
- new Thread() {
- public void run() {
- try {
- BufferedReader br =
- new BufferedReader(new InputStreamReader(socket.getInputStream()));
- PrintStream ps = new PrintStream(socket.getOutputStream());
-
- ps.println("欢迎咨询黑马程序员");
- System.out.println(br.readLine());
- ps.println("不一万就业不给一分钱");
- System.out.println(br.readLine());
- ps.println("不学拉到");
- socket.close();
- } catch (Exception e) {
-
- e.printStackTrace();
- }
- }
- }.start();
- }
- }
- }
编写网络应用就需要绑定一个端口号,尽量使用1024以上的,1024以下的基本上都被系统程序占用了。
常用端口
mysql: 3306
oracle: 1521
web: 80
tomcat: 8080
QQ: 4000
feiQ: 2425
三.网络协议
为计算机网络中进行数据交换而建立的规则、标准或约定的集合。
UDP
面向无连接,数据不安全,速度快。不区分客户端与服务端。
TCP
面向连接(三次握手),数据安全,速度略低。分为客户端和服务端。
三次握手: 客户端先向服务端发起请求, 服务端响应请求, 传输数据
四.Socket
通信的两端都有Socket。
网络通信其实就是Socket间的通信。
数据在两个Socket间通过IO流传输。
Socket在应用程序中创建,通过一种绑定机制与驱动程序建立关系,告诉自己所对应的IP和port。
五.UDP传输
1.发送
创建DatagramSocket, 随机端口号
创建DatagramPacket, 指定数据, 长度, 地址, 端口
使用DatagramSocket发送DatagramPacket
关闭DatagramSocket
2.接收
创建DatagramSocket, 指定端口号
创建DatagramPacket, 指定数组, 长度
使用DatagramSocket接收DatagramPacket
关闭DatagramSocket
从DatagramPacket中获取数据
3.接收方获取ip和端口号
String ip =packet.getAddress().getHostAddress();
int port = packet.getPort();
- import java.io.IOException;
- import java.net.DatagramPacket;
- import java.net.DatagramSocket;
- import java.net.InetAddress;
- import java.net.SocketException;
- import java.util.Scanner;
-
- public class Demo2_Send {
-
-
-
-
-
-
-
- public static void main(String[] args) throws IOException {
-
- DatagramSocket socket = new DatagramSocket();
- Scanner sc = new Scanner(System.in);
- while (true) {
- String line = sc.nextLine();
- if("quit".equals(line))
- break;
- DatagramPacket packet =
- new DatagramPacket(line.getBytes(), line.getBytes().length,InetAddress.getByName("127.0.0.1"), 6666);
- socket.send(packet);
- }
- socket.close();
- }
-
- }
- import java.io.IOException;
- import java.net.DatagramPacket;
- import java.net.DatagramSocket;
- import java.net.SocketException;
-
- public class Demo2_Receive {
-
-
-
-
-
-
-
-
-
-
- public static void main(String[] args) throws IOException {
- DatagramSocket socket = new DatagramSocket(6666);
- DatagramPacket packet = new DatagramPacket(new byte[1024], 1024);
- while(true) {
- socket.receive(packet);
- byte[] arr = packet.getData();
- int len = packet.getLength();
- String ip = packet.getAddress().getHostAddress();
- System.out.println(ip + ":" + new String(arr,0,len));
- }
- }
-
- }
多线程
- import java.io.IOException;
- import java.net.DatagramPacket;
- import java.net.DatagramSocket;
- import java.net.InetAddress;
- import java.net.SocketException;
- import java.net.UnknownHostException;
- import java.util.Scanner;
-
- public class Demo3_MoreThread {
-
-
-
-
- public static void main(String[] args) {
- new Receive().start();
- new Send().start();
- }
-
- }
-
- class Receive extends Thread {
- public void run() {
- try {
- DatagramSocket socket = new DatagramSocket(6666);
- DatagramPacket packet = new DatagramPacket(new byte[1024], 1024);
- while(true) {
- socket.receive(packet);
- byte[] arr = packet.getData();
- int len = packet.getLength();
- String ip = packet.getAddress().getHostAddress();
- System.out.println(ip + ":" + new String(arr,0,len));
- }
- } catch (Exception e) {
-
- e.printStackTrace();
- }
- }
- }
-
- class Send extends Thread {
- public void run() {
- try {
- DatagramSocket socket = new DatagramSocket();
- Scanner sc = new Scanner(System.in);
- while (true) {
- String line = sc.nextLine();
- if("quit".equals(line))
- break;
- DatagramPacket packet =
- new DatagramPacket(line.getBytes(), line.getBytes().length,InetAddress.getByName("192.168.33.186"), 6666);
- socket.send(packet);
- }
- socket.close();
- } catch (Exception e) {
-
- e.printStackTrace();
- }
- }
- }
六.TCP传输
1.客户端
创建Socket连接服务端(指定ip地址,端口号)通过ip地址找对应的服务器
调用Socket的getInputStream()和getOutputStream()方法获取和服务端相连的IO流
输入流可以读取服务端输出流写出的数据
输出流可以写出数据到服务端的输入流
- import java.io.BufferedReader;
- import java.io.BufferedWriter;
- import java.io.IOException;
- import java.io.InputStream;
- import java.io.InputStreamReader;
- import java.io.OutputStream;
- import java.io.OutputStreamWriter;
- import java.io.PrintStream;
- import java.net.Socket;
- import java.net.UnknownHostException;
-
- public class Demo2_Client {
-
-
-
-
-
-
-
-
-
-
- public static void main(String[] args) throws Exception {
- Socket socket = new Socket("127.0.0.1", 12345);
-
-
-
-
-
-
-
-
-
- BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
-
- PrintStream ps = new PrintStream(socket.getOutputStream());
- System.out.println(br.readLine());
- ps.println("我要报名就业班");
- System.out.println(br.readLine())
- ps.println("不学了");
-
- socket.close();
- }
-
- }
2.服务端
创建ServerSocket(需要指定端口号)
调用ServerSocket的accept()方法接收一个客户端请求,得到一个Socket
调用Socket的getInputStream()和getOutputStream()方法获取和客户端相连的IO流
输入流可以读取客户端输出流写出的数据
输出流可以写出数据到客户端的输入流
- import java.io.BufferedReader;
- import java.io.BufferedWriter;
- import java.io.IOException;
- import java.io.InputStream;
- import java.io.InputStreamReader;
- import java.io.OutputStream;
- import java.io.OutputStreamWriter;
- import java.io.PrintStream;
- import java.net.ServerSocket;
- import java.net.Socket;
-
- public class Demo2_Server {
-
-
-
-
-
-
-
-
-
-
- public static void main(String[] args) throws Exception {
- ServerSocket server = new ServerSocket(54321);
- Socket socket = server.accept();
-
-
-
-
-
-
-
-
- BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
-
-
-
- PrintStream ps = new PrintStream(socket.getOutputStream());
- ps.println("欢迎咨询传智播客");
- System.out.println(br.readLine());
- ps.println("报满了,等下一期吧");
- System.out.println(br.readLine());
- server.close();
- socket.close();
- }
-
- }
创建多线程的服务端,可以不断的向服务端访问
- import java.io.BufferedReader;
- import java.io.IOException;
- import java.io.InputStreamReader;
- import java.io.PrintStream;
- import java.net.ServerSocket;
- import java.net.Socket;
-
- public class Demo3_MoreThread {
-
-
-
-
-
- public static void main(String[] args) throws IOException {
- ServerSocket server = new ServerSocket(12345);
- while(true) {
- final Socket socket = server.accept();
- new Thread() {
- public void run() {
- try {
- BufferedReader br =
- new BufferedReader(new InputStreamReader(socket.getInputStream()));
- PrintStream ps = new PrintStream(socket.getOutputStream());
-
- ps.println("欢迎咨询黑马程序员");
- System.out.println(br.readLine());
- ps.println("不一万就业不给一分钱");
- System.out.println(br.readLine());
- ps.println("不学拉到");
- socket.close();
- } catch (Exception e) {
-
- e.printStackTrace();
- }
- }
- }.start();
- }
- }
-
- }
|