Java使用TCP实现数据传输

TCP所提供服务的主要特点：

　　1．面向连接的传输；

　　2．端到端的通信；

　　3．高可靠性，确保传输数据的正确性，不出现丢失或乱序；

　　4．全双工方式传输；

　　5．采用字节流方式，即以字节为单位传输字节序列；

　　6．紧急数据传送功能。

TCP传输需要建立客户端和服务器端，即Socket和Server Socket ， 建立连接后，通过Socket中的IO流进行数据的传输 。传输结束后关闭Socket。

客户端和服务器端是两个独立的应用程序。

以下是实现基本的TCP数据传输的Demo code：

package javase.day18;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.ServerSocket;
import java.net.Socket;

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

}

class TcpClient2{
public static void main(String[] args) throws Exception{
System.out.println("client start...");
Socket s = new Socket("192.168.1.2",10005);
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(s.getOutputStream()));
String sendDataStr=null;
while((sendDataStr=br.readLine())!=null){
if(sendDataStr.equals("bye")){
break;
}
bw.write(sendDataStr);
bw.newLine();
bw.flush();
}
bw.close();
}
}

class TcpServer2{
public static void main(String[] args) throws Exception{
System.out.println("server start...");
ServerSocket ss = new ServerSocket(10005);
Socket s = ss.accept();
BufferedReader br = new BufferedReader(new InputStreamReader(s.getInputStream()));
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(s.getOutputStream()));
String receiveDataStr=null;
while((receiveDataStr=br.readLine())!=null){
if(receiveDataStr.equals("bye")){
break;
}
System.out.println("receive data:"+receiveDataStr);
}
}
}

使用TCP实现文本文件上传的Demo code：

package javase.day18;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class UploadText {

public static void main(String[] args) {
// TODO Auto-generated method stub

}
}

class TextServer{
public static void main(String[] args) throws Exception{
System.out.println("Server start...");
ServerSocket ss = new ServerSocket(10008);
Socket s = ss.accept();
BufferedReader br = new BufferedReader(new InputStreamReader(s.getInputStream()));
PrintWriter out = new PrintWriter(new FileWriter("C:\\java_test\\server.txt"),true);
String line=null;
while((line=br.readLine())!=null){
System.out.println(line);
out.println(line);
}

PrintWriter pw = new PrintWriter(new OutputStreamWriter(s.getOutputStream()),true);
pw.println("upload successful");
pw.close();
s.close();
ss.close();
}
}

class TextClient{
public static void main(String[] args) throws Exception{
System.out.println("Client start...");
Socket clientSocket = new Socket("192.168.1.2",10008);
BufferedReader br = new BufferedReader(new FileReader("C:\\java_test\\SystemDemo.java"));
PrintWriter out = new PrintWriter(clientSocket.getOutputStream(),true);
String line=null;
while((line=br.readLine())!=null){
System.out.println(line);
out.println(line);
}
clientSocket.shutdownOutput();
BufferedReader br2 = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
String confirmMsgStr=br2.readLine();
System.out.println(confirmMsgStr);
br2.close();
clientSocket.close();

}
}

实现图片上传的Demo code：

package javase.day18;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.net.ServerSocket;
import java.net.Socket;

public class UploadImage {

public static void main(String[] args) {

}

}

class ImageClient{
public static void main(String[] args) throws Exception{
Socket imageClientSocket = new Socket("192.168.1.2",10010);
BufferedInputStream bis = new BufferedInputStream(new FileInputStream("C:\\java_test\\client\\生活用品01.jpg"));
BufferedOutputStream bos = new BufferedOutputStream(imageClientSocket.getOutputStream());
byte[] buf = new byte[1024*100];
int len = 0 ;
while((len=bis.read(buf))!=-1){
bos.write(buf,0,len);
}
imageClientSocket.shutdownOutput();
BufferedInputStream bis2 = new BufferedInputStream(imageClientSocket.getInputStream());
byte[] buf2 = new byte[1024];
int len2 = 0 ;
while((len2=bis2.read(buf2))!=-1){
System.out.println(new String(buf2,0,len2));
}
bis.close();
imageClientSocket.close();

}
}

class ImageServer{
public static void main(String[] args) throws Exception{
ServerSocket ss = new ServerSocket(10010);
Socket s = ss.accept();
BufferedInputStream bis = new BufferedInputStream(s.getInputStream());
BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("C:\\java_test\\server\\生活用品01.jpg"));
byte[] buf = new byte[1024*100];
int len = 0 ;
while((len=bis.read(buf))!=-1){
bos.write(buf, 0, len);
}
BufferedOutputStream bos2 = new BufferedOutputStream(s.getOutputStream());
bos2.write("upload successful".getBytes());
bos2.close();
s.close();
ss.close();
}
}