1、建立服务端，用于接收上传的文件。这里使用Socket，文件可能会比较大。采用多线程编程，防止并发。
package com.socket.service; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.OutputStream; import java.io.PushbackInputStream; import java.io.RandomAccessFile; import java.net.ServerSocket; import java.net.Socket; import java.text.SimpleDateFormat; import java.util.Date; import java.util.HashMap; import java.util.Map; import java.util.Properties; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import com.socket.service.util.StreamTool; public class FileServer { private ExecutorService executorService;// 线程池,实现网络多用户并发 private int port;// 监听端口 private boolean quit = false;// 退出 private ServerSocket server; private Map<Long, FileLog> datas = new HashMap<Long, FileLog>();// 存放断点数据 public FileServer(int port) { this.port = port; // 创建线程池，池中具有(cpu个数*50)条线程 executorService = Executors.newFixedThreadPool(Runtime.getRuntime() .availableProcessors() * 50); } /** * 退出 */ public void quit() { this.quit = true; try { server.close(); } catch (IOException e) { } } /** * 启动服务 * * @throws Exception */ public void start() throws Exception { server = new ServerSocket(port); while (!quit) { try { Socket socket = server.accept(); // 为支持多用户并发访问，采用线程池管理每一个用户的连接请求 executorService.execute(new SocketTask(socket)); } catch (Exception e) { // e.printStackTrace(); } } } private final class SocketTask implements Runnable { private Socket socket = null; public SocketTask(Socket socket) { this.socket = socket; } public void run() { try { System.out.println("accepted connection " + socket.getInetAddress() + ":" + socket.getPort()); PushbackInputStream inStream = new PushbackInputStream( socket.getInputStream()); // 得到客户端发来的第一行协议数据：Content-Length=143253434;filename=xxx.3gp;sourceid= // 如果用户初次上传文件，sourceid的值为空。 String head = StreamTool.readLine(inStream); System.out.println(head); if (head != null) { // 下面从协议数据中提取各项参数值 String[] items = head.split(";"); String filelength = items[0].substring(items[0].indexOf("=") + 1); String filename = items[1].substring(items[1].indexOf("=") + 1); String sourceid = items[2].substring(items[2].indexOf("=") + 1); long id = System.currentTimeMillis();// 生产资源id，如果需要唯一性，可以采用UUID FileLog log = null; if (sourceid != null && !"".equals(sourceid)) { id = Long.valueOf(sourceid); log = find(id);// 查找上传的文件是否存在上传记录 } File file = null; int position = 0; if (log == null) {// 如果不存在上传记录,为文件添加跟踪记录 String path = new SimpleDateFormat("yyyy/MM/dd/HH/mm").format(new Date()); File dir = new File("file/" + path); if (!dir.exists()) dir.mkdirs(); file = new File(dir, filename); if (file.exists()) {// 如果上传的文件发生重名，然后进行改名 filename = filename.substring(0,filename.indexOf(".") - 1) + dir.listFiles().length + filename.substring(filename.indexOf(".")); file = new File(dir, filename); } save(id, file); } else {// 如果存在上传记录,读取已经上传的数据长度 file = new File(log.getPath());// 从上传记录中得到文件的路径 if (file.exists()) { File logFile = new File(file.getParentFile(),file.getName() + ".log"); if (logFile.exists()) { Properties properties = new Properties(); properties.load(new FileInputStream(logFile)); position = Integer.valueOf(properties.getProperty("length"));// 读取已经上传的数据长度 } } } OutputStream outStream = socket.getOutputStream(); String response = "source + position + "\r\n"; // 服务器收到客户端的请求信息后，给客户端返回响应信息：sourceid=1274773833264;position=0 // sourceid由服务器端生成，唯一标识上传的文件，position指示客户端从文件的什么位置开始上传 outStream.write(response.getBytes()); RandomAccessFile fileOutStream = new RandomAccessFile(file, "rwd"); if (position == 0) fileOutStream.setLength(Integer.valueOf(filelength));// 设置文件长度 fileOutStream.seek(position);// 指定从文件的特定位置开始写入数据 byte[] buffer = new byte[1024]; int len = -1; int length = position; while ((len = inStream.read(buffer)) != -1) {// 从输入流中读取数据写入到文件中 fileOutStream.write(buffer, 0, len); length += len; Properties properties = new Properties(); properties.put("length", String.valueOf(length)); FileOutputStream logFile = new FileOutputStream( new File(file.getParentFile(), file.getName() + ".log")); properties.store(logFile, null);// 实时记录已经接收的文件长度 logFile.close(); } if (length == fileOutStream.length()) delete(id); fileOutStream.close(); inStream.close(); outStream.close(); file = null; } } catch (Exception e) { e.printStackTrace(); } finally { try { if (socket != null && !socket.isClosed()) socket.close(); } catch (IOException e) { } } } } public FileLog find(Long sourceid) { return datas.get(sourceid); } // 保存上传记录 public void save(Long id, File saveFile) { // 日后可以改成通过数据库存放 datas.put(id, new FileLog(id, saveFile.getAbsolutePath())); } // 当文件上传完毕，删除记录 public void delete(long sourceid) { if (datas.containsKey(sourceid)) datas.remove(sourceid); } private class FileLog { private Long id; private String path; public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getPath() { return path; } public void setPath(String path) { this.path = path; } public FileLog(Long id, String path) { this.id = id; this.path = path; } } }
2、通过swing编程启动服务：可以导出运行时jar文件。
package com.socket.service; import java.awt.BorderLayout; import java.awt.Frame; import java.awt.Label; import java.awt.event.WindowEvent; import java.awt.event.WindowListener; public class ServerWindow extends Frame { /** * */ private static final long serialVersionUID = -2723969590211090349L; private FileServer s = new FileServer(7788); private Label label; public ServerWindow(String title) { super(title); label = new Label(); add(label, BorderLayout.PAGE_START); label.setText("服务器已经启动"); this.addWindowListener(new WindowListener() { public void windowOpened(WindowEvent e) { new Thread(new Runnable() { public void run() { try { s.start(); } catch (Exception e) { // e.printStackTrace(); } } }).start(); } public void windowIconified(WindowEvent e) { } public void windowDeiconified(WindowEvent e) { } public void windowDeactivated(WindowEvent e) { } public void windowClosing(WindowEvent e) { s.quit(); System.exit(0); } public void windowClosed(WindowEvent e) { } public void windowActivated(WindowEvent e) { } }); } /** * @param args */ public static void main(String[] args) { ServerWindow window = new ServerWindow("文件上传服务端"); window.setSize(300, 300); window.setVisible(true); } }