java序列化

1.

package com.zh.serializable;
import java.io.*;
import java.util.*;
public class MySerializable {

 /**序列化与反序列化的运用,序列化就是把一个对象写到一个输入流中
  * 反序列化就是反过来
  * @param args
  * @throws IOException 
  * @throws Exception 
  */
 public static void main(String[] args) throws Exception {
  // TODO Auto-generated method stub
  //使用对象输出流
  ObjectOutputStream out=new ObjectOutputStream(new FileOutputStream("D:/abc.txt"));
  String obj1="hello";
  Date obj2=new Date();
  Customer obj3=new Customer("tom", 20);
  //序列化对象
  out.writeObject(obj1);
  out.writeObject(obj2);
  out.writeObject(obj3);
  out.close();
  //反序列化
  ObjectInputStream in=new ObjectInputStream(new FileInputStream("D:/abc.txt"));
  String obj11=(String)in.readObject();
  System.out.println("objll:"+obj11);
  System.out.println("objll==obj1:"+(obj11==obj1));
  System.out.println("obj11.equals(obj11):"+obj11.equals(obj11));
  
  Date obj22=(Date)in.readObject();
  System.out.println("obj22:"+obj22);
  System.out.println("obj2==obj22:"+(obj2==obj22));
  System.out.println("obj22.equals(obj2):"+obj2.equals(obj22));
  
  Customer obj33=(Customer)in.readObject();
  System.out.println("obj33:"+obj33);
  System.out.println("obj3==obj33:"+(obj3==obj33));
  System.out.println("obj3.equals(obj33):"+obj3.equals(obj33));
  System.out.println(obj33.getAge());
  
  in.close();
 }
}
//要想对象被序列化 就要继承Serializable
class Customer implements Serializable{
 private String name;
 private int age;
 
 public Customer(String name, int age) {
  this.name = name;
  this.age = age;
  System.out.println("call second constructor");
 }
 
 public boolean equals(Object o){
  if(this == o){
   return true;
  }
  if(! (o instanceof Customer)){
   return false;
  }
  final Customer other=(Customer)o;
  if(this.name.equals(other.name) && this.age==other.age){
   return true;
  }else{
   return false;
  }
 }
 
 
 public String toString(){
  return "name="+name+",age"+age;
 }

 public String getName() {
  return name;
 }

 public int getAge() {
  return age;
 }

 public void setName(String name) {
  this.name = name;
 }

 public void setAge(int age) {
  this.age = age;
 }
 
}



2.

package com.zh.serializable;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

public class MySerializable1 implements Serializable{

 /**
  * 用transient修饰可以不被序列化 因为在序列化后,容易被文件读取或拦截网络传输数据而
  * 偷窥
  * @param args
  */
 private String name;
 private transient String password;
 
 public MySerializable1(String name, String password) {
  super();
  this.name = name;
  this.password = password;
 }
 public String toString(){
  return name+" "+password;
 }
 public static void main(String[] args) throws IOException, ClassNotFoundException {
  // TODO Auto-generated method stub
  MySerializable1 user=new MySerializable1("zhouhai", "123456");
  System.out.println("before serialization: "+user);
  ByteArrayOutputStream buf=new ByteArrayOutputStream();
  
  //把user对象序列化到一个字节缓存中
  ObjectOutputStream o=new ObjectOutputStream(buf);
  o.writeObject(user);
  
  ObjectInputStream in=new ObjectInputStream(new ByteArrayInputStream(buf.toByteArray()));
  user=(MySerializable1)in.readObject();
  System.out.println("after serialization: "+user);
 }

}