客戶端：

import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.Socket;

/**
 * 檔案傳送客戶端主程式
 * @author admin_Hzw
 *
 */
public class BxClient {
	
	/**
	 * 程式main方法
	 * @param args
	 * @throws IOException
	 */
	public static void main(String[] args) throws IOException {
		int length = 0;
		double sumL = 0 ;
		byte[] sendBytes = null;
		Socket socket = null;
		DataOutputStream dos = null;
		FileInputStream fis = null;
		boolean bool = false;
		try {
			File file = new File("D:/天啊.zip"); //要傳輸的檔案路徑
			long l = file.length(); 
			socket = new Socket();  
			socket.connect(new InetSocketAddress("127.0.0.1", 48123));
			dos = new DataOutputStream(socket.getOutputStream());
			fis = new FileInputStream(file);      
			sendBytes = new byte[1024];  
			while ((length = fis.read(sendBytes, 0, sendBytes.length)) > 0) {
				sumL += length;  
				System.out.println("已傳輸："+((sumL/l)*100)+"%");
				dos.write(sendBytes, 0, length);
				dos.flush();
			} 
			//雖然資料型別不同，但JAVA會自動轉換成相同資料型別後在做比較
			if(sumL==l){
				bool = true;
			}
		}catch (Exception e) {
			System.out.println("客戶端檔案傳輸異常");
			bool = false;
			e.printStackTrace();  
		} finally{  
			if (dos != null)
				dos.close();
			if (fis != null)
				fis.close();   
			if (socket != null)
				socket.close();    
		}
		System.out.println(bool?"成功":"失敗");
	}
}
 

import java.io.DataInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Random;
import com.boxun.util.GetDate;


/**
 * 接收檔案服務
 * @author admin_Hzw
 *
 */
public class BxServerSocket {
	
	/**
	 * 工程main方法
	 * @param args
	 */
	public static void main(String[] args) {
		try {
			final ServerSocket server = new ServerSocket(48123);
			Thread th = new Thread(new Runnable() {
				public void run() {
					while (true) {
						try {  
							System.out.println("開始監聽...");
							/*
							 * 如果沒有訪問它會自動等待
							 */
							Socket socket = server.accept();
							System.out.println("有連結");
							receiveFile(socket);
						} catch (Exception e) {
							System.out.println("伺服器異常");
							e.printStackTrace();
						}
					}
				}
			});
			th.run(); //啟動執行緒執行
		} catch (Exception e) {
			e.printStackTrace();
		}     
	}

	public void run() {
	}

	/**
	 * 接收檔案方法
	 * @param socket
	 * @throws IOException
	 */
	public static void receiveFile(Socket socket) throws IOException {
		byte[] inputByte = null;
		int length = 0;
		DataInputStream dis = null;
		FileOutputStream fos = null;
		String filePath = "D:/temp/"+GetDate.getDate()+"SJ"+new Random().nextInt(10000)+".zip";
		try {
			try {
				dis = new DataInputStream(socket.getInputStream());
				File f = new File("D:/temp");
				if(!f.exists()){
					f.mkdir();  
				}
				/*  
				 * 檔案儲存位置  
				 */
				fos = new FileOutputStream(new File(filePath));    
				inputByte = new byte[1024];   
				System.out.println("開始接收資料...");  
				while ((length = dis.read(inputByte, 0, inputByte.length)) > 0) {
					fos.write(inputByte, 0, length);
					fos.flush();    
				}
				System.out.println("完成接收："+filePath);
			} finally {
				if (fos != null)
					fos.close();
				if (dis != null)
					dis.close();
				if (socket != null)
					socket.close(); 
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}
 

import java.text.SimpleDateFormat;
import java.util.Date;
/**
 * 時間工具類
 * @author admin_Hzw
 *
 */
public class GetDate {
	/**
	 * 時間格式到毫秒
	 */
	private static SimpleDateFormat df = new SimpleDateFormat("yyyyMMddHHmmssSSS");
	public static String getDate(){
		return df.format(new Date());
	}  
}