标签：java序列化   序列化   反序列化   保存对象   java反序列化   

1.概述

1.1序列化的含义和意义

所有需要保存在磁盘中的对象的类都必须是可序列化的，比如Web应用中需要保存到HttpSession或SevletContext属性中的应用。

2.使用对象流实现序列化

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

public class SerializeTest {
	public static void main(String[] args) {
		try {
			ObjectOutputStream oos=new ObjectOutputStream(
			new FileOutputStream("src/com/t/color.txt"));
			Color color=new Color("Red");
			oos.writeObject(color);//将对象写入输出流
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		try {
			ObjectInputStream ois=new ObjectInputStream(
			new FileInputStream("src/com/t/color.txt"));
			//从输入流中读取对象并强制转换成Color类
			Color col=(Color)ois.readObject();
			System.out.println(col.getColor());
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}

}
class Color implements Serializable{   
              private static final long serialVersionUID = -3398911857061187891L;
	private String color;
	public Color(String color) {
		this.color=color;
	}
	public String getColor() {
		return color;
	}
	public void setColor(String color) {
		this.color = color;
	}
}

3.对象引用的序列化

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

public class SerializeTest {
	public static void main(String[] args) {
		try {
			ObjectOutputStream oos=new ObjectOutputStream(
			new FileOutputStream("src/com/t/color.txt"));
			Color color=new Color("Red");
			Person person=new Person("lavor_zl", color);
			oos.writeObject(color);//将对象写入输出流
			oos.writeObject(person);//将对象写入输出流
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		try {
			ObjectInputStream ois=new ObjectInputStream(
			new FileInputStream("src/com/t/color.txt"));
			//从输入流中读取对象并强制转换成Color类
			Color col=(Color)ois.readObject();
			System.out.println(col.getColor());
                        Person per=(Person)ois.readObject();
                        System.out.println(per.getName());
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}

}
class Color implements Serializable{
	/**
	 * 
	 */
	private static final long serialVersionUID = -3398911857061187891L;
	private String color;
	public Color(String color) {
		this.color=color;
	}
	public String getColor() {
		return color;
	}
	public void setColor(String color) {
		this.color = color;
	}
}
class Person implements Serializable{
	/**
	 * 
	 */
	private static final long serialVersionUID = 3426878037487779564L;
	private String name;
	private Color color;
	public Person(String name,Color color) {
		this.name=name;
		this.color=color;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public Color getColor() {
		return color;
	}
	public void setColor(Color color) {
		this.color = color;
	}
	
}

4.自定义序列化

private void writeObject(java.io.ObjectOutputStream out)throws IOException
private void readObject(java.io.ObjectInputStream in)throws IOException,ClassNotFoundException
private void readObjectNoData()throws ObjectStreamException

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

public class Test implements Serializable{
	private static final long serialVersionUID = 6102026641912972144L;
	private int id;
	private String name;
	public Test(int id,String name) {
		this.id=id;
		this.name=name;
	}
	private void writeObject(ObjectOutputStream out)throws IOException{
		out.writeInt(id);
		out.writeChars(name);
	}
	private void readObject(ObjectInputStream in)throws IOException,ClassNotFoundException{
		this.id=in.readInt();
		//this.name=in.readLine()也可以，不过readLine()已经不推荐使用
		this.name=(String) in.readObject();
	}
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
}

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamException;
import java.io.Serializable;
import java.util.ArrayList;

public class Test implements Serializable{
	private int id;
	private String name;
	public Test(int id,String name) {
		this.id=id;
		this.name=name;
	}
	//重写writeReplace()方法，程序在序列化该类对象之前调用该方法
	private Object writeReplace()throws ObjectStreamException{
		ArrayList<Object> list=new ArrayList<Object>();
		list.add(id);
		list.add(name);
		return list;
	}
	public static void main(String[] args) {
		try{
			ObjectOutputStream oos=new ObjectOutputStream(new FileOutputStream("replace.txt"));
			ObjectInputStream ois=new ObjectInputStream(new FileInputStream("replace.txt"));
			Test test=new Test(1, "lavor_zl");
			oos.writeObject(test);
			ArrayList<Object> list=(ArrayList<Object>) ois.readObject();
			System.out.println(list);//输出：[1, lavor_zl]
		}catch(Exception e){
			e.printStackTrace();	
		}
	}
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
}

4.1另一种自定义序列化机制

Java序列化

标签：java序列化   序列化   反序列化   保存对象   java反序列化   

原文地址：http://blog.csdn.net/lavor_zl/article/details/42423183