Java Io 对象序列化和反序列化

Java 支持将任何对象进行序列化操作，序列化后的对象文件便可通过流进行网络传输。

1.      对象序列化就是将对象转换成字节序列，反之叫对象的反序列化

2.      序列化流ObjectOutputStream

3.      反序列化流 OjbectInputStream

4.      序列化的对象必须实现一个接口 Serializable

5.      如果在对象中不想序列化某个字段，那么可以在该字段中添加transient关键字

6.      对子类进行序列化操作时，父类的构造函数会被递归调用

7.      对子类进行反序列操作时，如果父类没有实现序列化接口那么父类的构造函数会被调用

写一个将Users对象序列化和反序列化的事例：

package com.dcz.io;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;

public class ObjectSerializableDemo {

	public static void main(String[] args) throws Exception {

		// 序列化对象
		File writeObjectFile = new File("d:\\users.dat");
		if(!writeObjectFile.exists()){
			writeObjectFile.createNewFile();
		}
		OutputStream fileOutputStream = new FileOutputStream(writeObjectFile);
		ObjectOutputStream oos = new ObjectOutputStream(fileOutputStream);

		Users user = new Users("admin","123456","管理员用户");
		oos.writeObject(user);
		oos.flush();
		oos.close();

		// 反序列化对象
		File readerObjectFile = new File("d:\\users.dat");
		InputStream fileInputStream = new FileInputStream(readerObjectFile);
		ObjectInputStream ois = new ObjectInputStream(fileInputStream);
		Users user2 = (Users)ois.readObject();
		System.out.println(user2);

	}

}

package com.dcz.io;

import java.io.Serializable;

public class Users implements Serializable{

	private static final long serialVersionUID = 4345979997811128454L;

	private String username;

	private String password;

	private String describe;

	public Users(){}

	public Users(String username, String password, String describe) {
		super();
		this.username = username;
		this.password = password;
		this.describe = describe;
	}

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

	public String getPassword() {
		return password;
	}

	public void setPassword(String password) {
		this.password = password;
	}

	public String getDescribe() {
		return describe;
	}

	public void setDescribe(String describe) {
		this.describe = describe;
	}

	@Override
	public String toString() {
		return "Users [username=" + username + ", password=" + password
				+ ", describe=" + describe + "]";
	}

}

如果不想默认序列化，想自定义序列化操作和反序列化操作就添加方法

private void writeObject(java.io.ObjectOutputStream s)
        throws java.io.IOException{
   // 在这里做处理序列化
}

 private void readObject(java.io.ObjectInputStream s)
        throws java.io.IOException, ClassNotFoundException {
   // 在这里做处理反序列化
}