java打印时间精确到毫秒

package net.floodlightcontroller.conflict;

import java.io.*;
import java.util.*;
import java.text.SimpleDateFormat;

public class OutputLog {
    public static void outPutLogToDeaktop(String fileName, String info) {
        File out_file = new File("/home/wangyong/Desktop/" + fileName);
        try {
            FileWriter fw = new FileWriter(out_file, out_file.exists());
            fw.write( new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS").format(new Date())
                    + " : " + info + "\n" );
            fw.close();
        } catch (IOException e) {
            System.out.println("FileWriter IOException!");
            e.printStackTrace();
        }

    }
}