public String read(String chunk_uuid) {
		Socket client = null;
		try {
			client = new Socket(InetAddress.getLocalHost(), port);// 򱾻port˿ڷͻ
		}catch (IOException e) {
			// TODO Auto-generated catch block
			return "-1";
		} 
		ObjectOutputStream out = null;
		try {out = new ObjectOutputStream(client.getOutputStream());} 
			catch (IOException e) {e.printStackTrace();}
		ObjectInputStream in = null;
		try {
			in = new ObjectInputStream(client.getInputStream());
		} catch (IOException e) {
			e.printStackTrace();
		}		
		String[] s = new String[] { "read", chunk_uuid};
		try {// 
			out.writeObject(s);
			out.flush(); // ˢʹServerյַ		
		} catch (IOException e) {
			e.printStackTrace();
		}  
		String[] arr = null;
		try {//
			arr = (String[]) in.readObject();
			client.close();

		} catch (ClassNotFoundException | IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} 
		return arr[0].toString();
	}