JAVA之旅(三十三)

1、JAVA之旅（三十三）一.TCP說完UDP，我們就來說下我們應該重點掌握的TCP了TCP傳輸 Socket和ServiceSocket建立客戶端和服務端建立連接后，通過Socket中的IO流進行數(shù)據(jù)的傳輸關閉Socket同樣的，我們的客戶端和服務端都是兩個獨立的應用我們通過查閱API文檔發(fā)現(xiàn)，該對象在建立的時候，就可以去連接指定主機，因為tcp是面向連接的，所以在建立socket服務時，就要有服務存在，并成功連接，形成通路后，在該通道進行數(shù)據(jù)傳輸所以我們用代碼來看下他的步驟客戶端package com.lgl.hellojava;import java.io.IOException;impor

2、t java.io.InputStream;import java.io.OutputStream;import .ServerSocket;import .Socket;import .UnknownHostException;public class TcpClient public static void main(String args) try /1.創(chuàng)建客戶端的服務，傳地址和端口 Socket s = new Socket("192.168.1.102",10000); /2.為了發(fā)送數(shù)據(jù)，應該獲得socket流中的輸出流 OutputStream out =

3、s.getOutputStream(); out.write("你好".getBytes(); s.close(); catch (UnknownHostException e) / TODO Auto-generated catch block e.printStackTrace(); catch (IOException e) / TODO Auto-generated catch block e.printStackTrace(); 服務端package com.lgl.hellojava;import java.io.IOException;import java.

4、io.InputStream;import .ServerSocket;import .Socket;/* * 定義端點接收數(shù)據(jù)打印出來 * 服務端： * 1.建立服務端的socket服務，servicesocket,并監(jiān)聽一個端口 * 2.獲取連接過來的客戶端對象，通過accept方法，這個方法是阻塞的，沒有連接就會等 * 3.客戶端如果發(fā)過來數(shù)據(jù)，那么服務端要使用對應的客戶端對象，并獲取到該對象的讀取流 * 4.關閉服務端（可選操作） * author LGL * */public class TcpService public static void main(String args)

5、try /1.建立連接，監(jiān)聽端口 ServerSocket ss = new ServerSocket(10000); /2.連接客戶端對象 Socket accept = ss.accept(); /獲取ip String ip = accept.getInetAddress().getHostAddress(); /3.獲取客戶端發(fā)送過來的數(shù)據(jù) InputStream in = accept.getInputStream(); /4.開始讀取 byte buf = new byte1024; int len = in.read(buf); System.out.println(new St

6、ring(buf,0,len); /5.關閉 ss.close(); catch (IOException e) / TODO Auto-generated catch block e.printStackTrace(); 二.TCP互相傳輸我們在來寫一個實例去說明，他們的互訪動作，這里為了寫起來方便，就寫在一個類中了package com.lgl.hellojava;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import .ServerSocket;import .Soc

7、ket;import .UnknownHostException;/* * 客戶端發(fā)送信息，服務端收到，反饋信息 * * author LGL * */public class Tcp public static void main(String args) try Socket s = new Socket("192.168.1.102", 10005); OutputStream out = s.getOutputStream(); out.write("我是客戶端".getBytes(); InputStream in = s.getInputSt

8、ream(); byte buf = new byte1024; int len = in.read(buf); System.out.println(new String(buf, 0, len); s.close(); catch (UnknownHostException e) / TODO Auto-generated catch block e.printStackTrace(); catch (IOException e) / TODO Auto-generated catch block e.printStackTrace(); /* * 服務端 * author LGL * *

9、/class Server public static void main(String args) try ServerSocket ss = new ServerSocket(10005); Socket s = ss.accept(); InputStream in = s.getInputStream(); byte buf = new byte1024; int len = in.read(buf); System.out.println(new String(buf, 0, len); OutputStream out = s.getOutputStream(); out.writ

10、e("收到后反饋".getBytes(); s.close(); ss.close(); catch (IOException e) / TODO Auto-generated catch block e.printStackTrace(); 三.復制文件同樣的這里也是使用的流，我們具體來看下怎么去操作，我們同樣的，寫在一個類中package com.lgl.socket;import java.io.BufferedReader;import java.io.FileReader;import java.io.FileWriter;import java.io.IOExc

11、eption;import java.io.InputStreamReader;import java.io.PrintWriter;import .ServerSocket;import .Socket;import .UnknownHostException;public class FileClient public static void main(String args) try Socket s = new Socket("192.168.1.102", 10006); BufferedReader bufr = new BufferedReader(new F

12、ileReader("test.txt"); PrintWriter pw = new PrintWriter(s.getOutputStream(), true); String line = null; while (line = bufr.readLine() != null) pw.println(line); pw.print("over"); BufferedReader bufIn = new BufferedReader(new InputStreamReader( s.getInputStream(); String str = buf

13、In.readLine(); System.out.println(str); bufr.close(); s.close(); catch (UnknownHostException e) / TODO Auto-generated catch block e.printStackTrace(); catch (IOException e) / TODO Auto-generated catch block e.printStackTrace(); class FileServer public static void main(String args) try ServerSocket s

14、s = new ServerSocket(10006); Socket s = ss.accept(); BufferedReader bufIn = new BufferedReader(new InputStreamReader( s.getInputStream(); PrintWriter out = new PrintWriter(new FileWriter("test1.txt"), true); String line = null; while (line = bufIn.readLine() != null) if ("over".e

15、quals(line) break; out.println(line); PrintWriter pw = new PrintWriter(s.getOutputStream(), true); pw.println("上傳成功"); out.close(); s.close(); ss.close(); catch (IOException e) / TODO Auto-generated catch block e.printStackTrace(); 四.上傳圖片我們再來看下圖片是怎么上傳的，我們先來分析下步驟客戶端1.服務端點2.讀取客戶端已有的圖片數(shù)據(jù)3.通過s

16、ocket，發(fā)送給服務端4.讀取服務端反饋的信息5.關閉資源* * 客戶端 * * author LGL * */public class PicClient public static void main(String args) try Socket s = new Socket("192.168.1.102", 10009); FileInputStream fis = new FileInputStream("1.png"); OutputStream out = s.getOutputStream(); byte buf = new byte1

17、024; int len = 0; while (len = fis.read(buf) != -1) out.write(buf, 0, len); /告訴服務端數(shù)據(jù)寫完 s.shutdownInput(); InputStream in = s.getInputStream(); byte bufn = new byte1024; int num = in.read(bufn); System.out.println(new String(bufn, 0, num); fis.close(); s.close(); catch (UnknownHostException e) / TODO

18、 Auto-generated catch block e.printStackTrace(); catch (IOException e) / TODO Auto-generated catch block e.printStackTrace(); 服務端直接看代碼/* * 服務端 * author LGL * */class PicServer public static void main(String args) try ServerSocket ss = new ServerSocket(10009); Socket s = cept(); InputStream in = s.ge

19、tInputStream(); FileOutputStream fos = new FileOutputStream("2.png"); byte buf = new byte1024; int len = 0; while (len = in.read(buf) != -1) fos.write(buf, 0, len); OutputStream out = s.getOutputStream(); out.write("上傳成功".getBytes(); fos.close(); s.close(); ss.close(); catch (IOE

20、xception e) / TODO Auto-generated catch block e.printStackTrace(); 其實跟I/O區(qū)別真不大，但是概念一定要了解清楚五.多并發(fā)上傳多并發(fā)這個概念就是多人互動了，這對服務器的負荷還是有考究的，這里呢，我們就模擬一下，多人上傳圖片的場景，我們是怎么做的？我們還是在上傳圖片的那份代碼上更改首先我們可以確定的是，這是服務端的代碼這個服務端有個局限性，當A客戶端連接之后，被服務端獲取到，服務端就在執(zhí)行代碼了，這個時候如果B客戶端連接只有等待，這就是我們需要多并發(fā)的原因了，為了讓多個客戶端同時連接，服務端最好就是講每個客戶端封裝到一個單獨的線

21、程中，這樣就可以同時處理多個客戶端請求如何定義線程？只要明確了每個客戶端要在服務端執(zhí)行的代碼即可/* * 服務端 * * author LGL * */class PicServer public static void main(String args) try ServerSocket ss = new ServerSocket(10009); while (true) Socket s = ss.accept(); new Thread(new PicThread(s).start(); catch (IOException e) / TODO Auto-generated catch

22、block e.printStackTrace(); /* * 并發(fā)線程 * author LGL * */class PicThread implements Runnable private Socket s; public PicThread(Socket s) this.s = s; Override public void run() try String ip = s.getInetAddress().getHostAddress(); System.out.println("ip：" + ip); long millis = System.currentTim

23、eMillis(); File file = new File(millis + ".png"); InputStream in = s.getInputStream(); FileOutputStream fos = new FileOutputStream(file); byte buf = new byte1024; int len = 0; while (len = in.read(buf) != -1) fos.write(buf, 0, len); OutputStream out = s.getOutputStream(); out.write("上

24、傳成功".getBytes(); fos.close(); s.close(); catch (Exception e) throw new RuntimeException("上傳失敗"); 其實我寫的代碼還是有點爛的，但是思想在就好，我們得先把思想學會了六.多并發(fā)登錄上面說的多并發(fā)的上傳，實在服務端端，現(xiàn)在我們來說下登錄，是作用在客戶端package com.lgl.socket;import java.io.BufferedReader;import java.io.FileReader;import java.io.IOException;import j

25、ava.io.InputStreamReader;import java.io.PrintWriter;import .ServerSocket;import .Socket;import .UnknownHostException;public class LoginClient public static void main(String args) try Socket s = new Socket("192.168.1.102", 10008); BufferedReader bufr = new BufferedReader(new InputStreamRead

26、er( System.in); PrintWriter out = new PrintWriter(s.getOutputStream(), true); BufferedReader bufIn = new BufferedReader(new InputStreamReader( s.getInputStream(); for (int i = 0; i < 3; i+) String line = bufr.readLine(); if (line = null) break; out.println(line); String info = bufIn.readLine(); S

27、ystem.out.println("info:" + info); if (info.contains("歡迎") break; bufr.close(); s.close(); catch (UnknownHostException e) / TODO Auto-generated catch block e.printStackTrace(); catch (IOException e) / TODO Auto-generated catch block e.printStackTrace(); /* * 服務端 * * author LGL * */class LoginServer public static void main(String args) try ServerSocket ss = new ServerSocket(10008); while (true) Socket s = ss.accept(); new Thread(new UserThread(s).start(); catch (IOException e) / TODO Auto-generated catch block e.printStackTrace(); /*