Serializable序列化(三)

package serializ;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
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;

/**
 * 自定义序列化 默认的序列化机制是自动完成的,
 * 如果想要修改序列化过程 要实现几个private级别方法
 * private void writeObject(ObjectOutputStream oos)
 * private void readObject(ObjectInputStream ois)
 * 并且该类还是正常实现Serializable接口,按照正常方式序列化
 * 不过在序列化过程中会自动调用你实现的 writeObject和readObject方法
 * 
 * @author yli
 * 
 */
public class CustomSerializable {

	public static void main(String[] args) {
		String file = "src/serializ/account.dat";

		Account acc = new Account("100034", 200d);
		System.out.println(acc);
		writeObject(acc, file);

		Account acc1 = (Account) readObject(file);
		System.out.println(acc1);
	}

	// 序列化对象
	private static void writeObject(Object obj, String file) {
		ObjectOutputStream oos = null;
		try {
			oos = new ObjectOutputStream(new BufferedOutputStream(new FileOutputStream(file)));
			oos.writeObject(obj);
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				oos.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}

	// 反序列化
	private static Object readObject(String file) {
		ObjectInputStream ois = null;
		Object obj = null;
		try {
			ois = new ObjectInputStream(new BufferedInputStream(new FileInputStream(file)));
			obj = ois.readObject();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		} finally {
			try {
				ois.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		return obj;
	}
}

/**
 * 实现writeObject和readObject方法
 * @author liyu
 *
 */
class Account implements Serializable{
	private static final long serialVersionUID = 1589558240016731037L;
	String name;
	double balance;

	public Account(String name, double balance) {
		this.name = name;
		this.balance = balance;
	}

	public void setBalance(double balance) {
		this.balance = balance;
	}
	
	public String toString(){
		return String.format("{name:%s,balance=%s}", name, balance);
	}

	private void writeObject(ObjectOutputStream oos) throws IOException {
		// defaultWriteObject会自动把类的描述信息以及签名写入
		// 并且将String类型字段自动write
		oos.defaultWriteObject();
		// 因此此处指write了balance字段
		oos.writeDouble(balance);
	}

	private void readObject(ObjectInputStream ois)
			throws ClassNotFoundException, IOException {
		// defaultReadObject会自动把类的描述信息以及签名写入
		// 并且将String类型字段自动read出来
		ois.defaultReadObject();
		// 因此此处只read了balance字段
		ois.readDouble();
	}
}