transient关键字

transient关键字用于声明序列化的时候不被存储

public class Test {
	public static void main(String[] args) throws Exception {
		String logFile = "e:/login.log";
		Login zhangs = new Login("zhangs", "1234");
		System.out.println(zhangs);
		// {username:zhangs, password:1234, logTime:Wed May 25 15:17:45 CST 2011}
		ObjectOutputStream o = new ObjectOutputStream(new FileOutputStream(logFile));
		o.writeObject(zhangs);
		o.close();
		wait(1);
		ObjectInputStream in = new ObjectInputStream(new FileInputStream(logFile));
		Login zhangsLog;
		zhangsLog = (Login) in.readObject();
		in.close();
		System.out.println(zhangsLog);
		// {username:zhangs, password:null, logTime:Wed May 25 15:17:45 CST 2011}
	}

	private static void wait(int seconds) {
		long delay = System.currentTimeMillis() + seconds * 1000;
		while (true) {
			if(System.currentTimeMillis() >= delay){
				break;
			}
		}
	}
}

class Login implements Serializable {
	private static final long serialVersionUID = 1L;
	private String username;
	private transient String password;
	private Date logTime = new Date();

	Login(String name, String pwd) {
		username = name;
		password = pwd;
	}

	public String toString() {
		return "{username:" + username + ", password:" + password
				+ ", logTime:" + logTime + "}";
	}
}