对象的序列化与反序列化

概念
把对象转换成字节序列的为对象的序列化
把字节序列回恢复成对象为反序列化

serialVersionUID序列化版本标识
用于在反序列化时版本的判断。如果没有该属性，在类序列化后如果对该类做了修改，它默认的serialVersionUID就会发生变化，在反序列化时会对比硬盘与Class中的serialVersionUID，如果不相等处于安全考虑会禁止序列化并抛出错误：
1 Exception in thread “main” java.io.InvalidClassException: Customer;
2 local class incompatible:
3 stream classdesc serialVersionUID = -88175599799432325,
4 local class serialVersionUID = -5182532647273106745

序列化相关对象
ObjectOutputStream 序列化输出流
在输出序列化字节数据时不用创建指定的文件名
ObjectInputStream 序列化输入流

    /**
     * 序列化对象
     */
    @Test
    public void objectOutStream() throws IOException {

        ObjectOutputStream objectOutputStream = new ObjectOutputStream(new FileOutputStream(new File("D:\\aa.txt")));
        objectOutputStream.writeObject(new Person("张三", "重庆",13));
        objectOutputStream.close();


    }

    /**
     * 通过类文件进行反序列化
     */
    @Test
    public void objectInputStream() throws IOException, ClassNotFoundException {
        ObjectInputStream objectInputStream = new ObjectInputStream(new FileInputStream(new File("D:\\aa.txt")));
        Person person = (Person) objectInputStream.readObject();
        System.out.println(person);
        objectInputStream.close();
    }


}


class Person implements Serializable {

    private static final long serialVersionUID = 8289429897296233280L;

    private String name;
    private String home;
    private Integer age;

    public Person(String name, String home, Integer age) {
        this.name = name;
        this.home = home;
        this.age = age;
    }

    public String getHome() {
        return home;
    }

    public void setHome(String home) {
        this.home = home;
    }

    public String getName() {
        return name;
    }

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

    public Integer getAge() {
        return age;
    }

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

    @Override
    public String toString() {
        return "Person{" +
                "name='" + name + '\'' +
                ", home='" + home + '\'' +
                ", age=" + age +
                '}';
    }

Intellij IDEA 自动生成 serialVersionUID
Setting->Inspections->Serialization issues->Serializable class without ’serialVersionUID’
选上以后，在你的class中：Alt+Enter就会提示自动创建serialVersionUID了。