Java IO 中对象的序列化操作

 

Java IO 中对象的序列化操作

博客分类： JavaSe

Java 面试 ITeye C C++

Java IO 中对象的序列化操作

这是一个在IO中比较基础的问题,但是因为很少用到,很容易遗忘,面试的时候可能会遇到,所以记录到博客上,防止忘记

 

其实代码很简单:主要是用到两个类ObjectInputStream 和ObjectOutputStream 分别实现对类的读取和写入

 

注意的一点是:要序列化的类应该实现Serialiable接口,其实是一个空的接口,包含写入和读取的测试程序代码

 

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.UUID;


public class TestSerialized {
    /**
     * 把对象写入文件
     * @throws Exception
     */
    public static void WriteObject(Object obj)throws Exception{
        FileOutputStream fis = new FileOutputStream(new File("c:\\object.obj"));
        ObjectOutputStream oos = new ObjectOutputStream(fis);
        oos.writeObject(obj);
        oos.close();
    }
    /**
     * 从文件读取对象
     * @return
     * @throws Exception
     */
    public static Object readObject() throws Exception {
        FileInputStream fis = new FileInputStream(new File("c:\\object.obj"));
        ObjectInputStream oos = new ObjectInputStream(fis);
        return oos.readObject();
    }
    public static void testWrite() throws Exception{
        SerializedClass sc = new SerializedClass();
        sc.setId(UUID.randomUUID().toString());
        sc.setName("zhougege");
        WriteObject(sc);
        System.out.println("写入的对象:");
        System.out.println(sc.getId());
        System.out.println(sc.getName());
    }
    public static void testRead() throws Exception{
        Object obj = readObject();
        SerializedClass sc = (SerializedClass)obj;
        System.out.println("读取到的对象:");
        System.out.println(sc.getId());
        System.out.println(sc.getName());
    }
    public static void main(String[] args) throws Exception {
        testWrite();
        testRead();
    }
}

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.UUID;


public class TestSerialized {
	/**
	 * 把对象写入文件
	 * @throws Exception
	 */
	public static void WriteObject(Object obj)throws Exception{
		FileOutputStream fis = new FileOutputStream(new File("c:\\object.obj"));
		ObjectOutputStream oos = new ObjectOutputStream(fis);
		oos.writeObject(obj);
		oos.close();
	}
	/**
	 * 从文件读取对象
	 * @return
	 * @throws Exception
	 */
	public static Object readObject() throws Exception {
		FileInputStream fis = new FileInputStream(new File("c:\\object.obj"));
		ObjectInputStream oos = new ObjectInputStream(fis);
		return oos.readObject();
	}
	public static void testWrite() throws Exception{
		SerializedClass sc = new SerializedClass();
		sc.setId(UUID.randomUUID().toString());
		sc.setName("zhougege");
		WriteObject(sc);
		System.out.println("写入的对象:");
		System.out.println(sc.getId());
		System.out.println(sc.getName());
	}
	public static void testRead() throws Exception{
		Object obj = readObject();
		SerializedClass sc = (SerializedClass)obj;
		System.out.println("读取到的对象:");
		System.out.println(sc.getId());
		System.out.println(sc.getName());
	}
	public static void main(String[] args) throws Exception {
		testWrite();
		testRead();
	}
}

 写入对象的核心代码

/**
 * 把对象写入文件
 * @throws Exception
 */
public static void WriteObject(Object obj)throws Exception{
    FileOutputStream fis = new FileOutputStream(new File("c:\\object.obj"));
    ObjectOutputStream oos = new ObjectOutputStream(fis);
    oos.writeObject(obj);
    oos.close();
}

	/**
	 * 把对象写入文件
	 * @throws Exception
	 */
	public static void WriteObject(Object obj)throws Exception{
		FileOutputStream fis = new FileOutputStream(new File("c:\\object.obj"));
		ObjectOutputStream oos = new ObjectOutputStream(fis);
		oos.writeObject(obj);
		oos.close();
	}

 

读取对象的核心代码

/**
 * 从文件读取对象
 * @return
 * @throws Exception
 */
public static Object readObject() throws Exception {
    FileInputStream fis = new FileInputStream(new File("c:\\object.obj"));
    ObjectInputStream oos = new ObjectInputStream(fis);
    return oos.readObject();
}