Java transient 关键字用法

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

public class LoggingInfo implements java.io.Serializable {

private static final long serialVersionUID = 1L;
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;
}

public static void main(String[] args) {

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) {// deal with exception

}

// To read the object back, we can write
try {
ObjectInputStream in = new ObjectInputStream(new FileInputStream(
"logInfo.out"));
LoggingInfo logInfo1 = (LoggingInfo) in.readObject();
System.out.println(logInfo1.toString());
} catch (Exception e) {// deal with exception

}
}
}