Java中的serialize接口与transient关键字

package com.jd;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Date;

public class App {
public static void main(String[] args) {
//现在我们创建一个类的实例,并且串行化(serialize)它,然后将这个串行化对象写入磁盘

LoggingInfo logInfo = new LoggingInfo("MIKE", "MECHANICS");
System.out.println(logInfo.toString());
try {
ObjectOutputStream o = new ObjectOutputStream(new FileOutputStream("logInfo.out"));
o.writeObject(logInfo);
o.close();
} catch (Exception e) {
}
//读出上面写入文件中的串行化对像,发现transient标识的pwd属性值并不会被存储

try {
ObjectInputStream in = new ObjectInputStream(
new FileInputStream("logInfo.out"));
logInfo = (LoggingInfo) in.readObject();
System.out.println(logInfo.toString());
}
catch (Exception e) {
}
}

static class LoggingInfo implements java.io.Serializable {
private Date loggingDate = new Date();
private String uid;
private transient String pwd;

LoggingInfo(String user, String password) {
uid = user;
pwd = password;
}

public String toString() {
String password = null;
if (pwd == null) {
password = "NOT SET";
} else {
password = pwd;
}
return "logon info: \n " + "user: " + uid +
"\n logging date : " + loggingDate.toString() +
"\n password: " + password;
}
}
}

总之，transient关键字是为了安全性，防止这种类型的数据在IO中存储（例如网络传输或本地存盘）