package com.kook.ch15Project; import java.io.*; import java.util.*; public class Ex15_20 { public static void main(String[] args) { try { String fileName = "UserInfo.ser"; //직렬화 값을 작성할 파일 FileOutputStream fos = new FileOutputStream(fileName); BufferedOutputStream bos = new BufferedOutputStream(fos); ObjectOutputStream out = new ObjectOutputStream(bos); UserInfo u1 = new UserInfo("JavaMan", "1234..