Java基于Socket实现文件传输示例

package sterning; import java.io.BufferedInputStream; importjava.io.DataInputStream; import java.io.DataOutputStream; importjava.io.File; import java.io.FileInputStream; importjava.net.ServerSocket; import java.net.Socket; public classServerTest { int port = 8821; void start() { Socket s = null; try {ServerSocket ss = new ServerSocket(port); while (true) { //选择进行传输的文件 String filePath = "D:\lib.rar"; File fi = newFile(filePath); System.out.println("文件长度:" + (int) fi.length()); //public Socket accept() throws //IOException侦听并接受到此套接字的连接。此方法在进行连接之前一直阻塞。 s = ss.accept();System.out.println("建立socket链接"); DataInputStream dis = newDataInputStream(new BufferedInputStream( s.getInputStream()));dis.readByte(); DataInputStream fis = new DataInputStream(newBufferedInputStream( new FileInputStream(filePath)));DataOutputStream ps = new DataOutputStream(s.getOutputStream());//将文件名及长度传给客户端。这里要真正适用所有平台，例如中文名的处理， //还需要加工，具体可以参见Think In Java4th里有现成的代码。 ps.writeUTF(fi.getName()); ps.flush();ps.writeLong((long) fi.length()); ps.flush(); int bufferSize =8192; byte[] buf = new byte[bufferSize]; while (true) { int read =0; if (fis != null) { read = fis.read(buf); } if (read == -1) {break; } ps.write(buf, 0, read); } ps.flush(); //注意关闭socket链接哦，不然客户端会等待server的数据过来， // 直到socket超时，导致数据不完整。fis.close(); s.close(); System.out.println("文件传输完成"); } } catch(Exception e) { e.printStackTrace(); } } public static voidmain(String arg[]) { new ServerTest().start(); } } 2.socket的Util辅助类package sterning; import java.net.*; import java.io.*; public classClientSocket { private String ip; private int port; private Socketsocket = null; DataOutputStream out = null; DataInputStreamgetMessageStream = null; public ClientSocket(String ip, int port) {this.ip = ip; this.port = port; } public void CreateConnection()throws Exception { try { socket = new Socket(ip, port); } catch(Exception e) { e.printStackTrace(); if (socket != null)socket.close(); throw e; } finally { } } public voidsendMessage(String sendMessage) throws Exception { try { out = newDataOutputStream(socket.getOutputStream()); if(sendMessage.equals("Windows")) { out.writeByte(0x1); out.flush();return; } if (sendMessage.equals("Unix")) { out.writeByte(0x2);out.flush(); return; } if (sendMessage.equals("Linux")) {out.writeByte(0x3); out.flush(); } else {out.writeUTF(sendMessage); out.flush(); } } catch (Exception e) {e.printStackTrace(); if (out != null) out.close(); throw e; }finally { } } public DataInputStream getMessageStream() throwsException { try { getMessageStream = new DataInputStream(newBufferedInputStream( socket.getInputStream())); returngetMessageStream; } catch (Exception e) { e.printStackTrace(); if(getMessageStream != null) getMessageStream.close(); throw e; }finally { } } public void shutDownConnection() { try { if (out !=null) out.close(); if (getMessageStream != null)getMessageStream.close(); if (socket != null) socket.close(); }catch (Exception e) { } } } 3.客户端 package sterning; importjava.io.BufferedOutputStream; import java.io.DataInputStream;import java.io.DataOutputStream; import java.io.FileOutputStream;public class ClientTest { private ClientSocket cs = null; privateString ip = "localhost"; // 设置成服务器IP private int port = 8821;private String sendMessage = "Windwos"; public ClientTest() { try {if (createConnection()) { sendMessage(); getMessage(); } } catch(Exception ex) { ex.printStackTrace(); } } private booleancreateConnection() { cs = new ClientSocket(ip, port); try {cs.CreateConnection(); System.out.print("连接服务器成功!" + " "); returntrue; } catch (Exception e) { System.out.print("连接服务器失败!" + " ");return false; } } private void sendMessage() { if (cs == null)return; try { cs.sendMessage(sendMessage); } catch (Exception e) {System.out.print("发送消息失败!" + " "); } } private void getMessage() {if (cs == null) return; DataInputStream inputStream = null; try {inputStream = cs.getMessageStream(); } catch (Exception e) {System.out.print("接收消息缓存错误 "); return; } try {//本地保存路径，文件名会自动从服务器端继承而来。 String savePath = "E:\"; int bufferSize =8192; byte[] buf = new byte[bufferSize]; int passedlen = 0; longlen=0; savePath += inputStream.readUTF(); DataOutputStream fileOut= new DataOutputStream(new BufferedOutputStream( newBufferedOutputStream(new FileOutputStream(savePath)))); len =inputStream.readLong(); System.out.println("文件的长度为:" + len + " ");System.out.println("开始接收文件!" + " "); while (true) { int read = 0;if (inputStream != null) { read = inputStream.read(buf); }passedlen += read; if (read == -1) { break; }//下面进度条本为图形界面的prograssBar做的，这里如果是打文件， //可能会重复打印出一些相同的百分比System.out.println("文件接收了" + (passedlen * 100/ len) + "% ");fileOut.write(buf, 0, read); } System.out.println("接收完成，文件存为" +savePath + " "); fileOut.close(); } catch (Exception e) {System.out.println("接收消息错误" + " "); return; } } public static voidmain(String arg[]) { new ClientTest(); } }