public File getFile( String fname ) {
		JFileChooser fc = new JFileChooser();
		fc.setSelectedFile( new File(fname) );
		int result = fc.showSaveDialog(new JFrame());
		File recvfile;
		if (result == JFileChooser.APPROVE_OPTION) {
			recvfile = fc.getSelectedFile();
			filename = recvfile.getAbsolutePath();
			//System.out.println( filename );
			jLabel1.setText("接收" + filename);
			jLabel2.setText("已完成 0 bytes / " + filesize + " bytes");
			return recvfile;
		}
		else return null;
	}