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Android 序列化对象方法：

• 实现Serializable接口，Java自带；
• 实现Parcelable接口，android特有接口，效率高于Serializable接口，支持Intent数据传递，也可用于跨进程通讯（IPC）；

实现Parcelable接口方法步骤：

Java 实体实现 Parcelable 接口，且需要实现以下几个方法：

1. describeContents方法。内容接口描述，默认返回0就可以;

2. writeToParcel 方法。该方法将类的数据写入外部提供的Parcel中.即打包需要传递的数据到Parcel容器保存，以便从parcel容器获取数据，该方法声明如下：writeToParcel (Parcel dest, int flags)

3. 静态的Parcelable.Creator接口，本接口有两个方法：

createFromParcel(Parcel in)  
//从Parcel容器中读取传递数据值，封装成Parcelable对象返回逻辑层。

newArray(int size) 
//创建一个类型为T，长度为size的数组，仅一句话（return new T[size])即可。方法是供外部类反序列化本类数组使用。

Demo 代码实现

1. 建立实现Parcelable接口Person类

/**
 * Created by JerryLiu on 2016/7/21.
 */
public class Person implements Parcelable {


    private static final String TAG = "LiuDongBing";

    private String userName;
    private String passWord;


    public Person() {
        Log.d(TAG, "Person(): ");
    }

    public Person(String userName, String passWord) {
        Log.d(TAG, "Person() called with: " + "userName = [" + userName + "], passWord = [" + passWord + "]");
        this.userName = userName;
        this.passWord = passWord;
    }

    public String getUserName() {
        Log.d(TAG, "getUserName: = " + userName);
        return userName;
    }

    public void setUserName(String userName) {
        Log.d(TAG, "setUserName: = " + userName);
        Log.d(TAG, "setUserName() called with: " + "userName = [" + userName + "]");
        this.userName = userName;
    }

    public String getPassWord() {
        Log.d(TAG, "getPassWord: =  " + passWord);
        return passWord;
    }

    public void setPassWord(String passWord) {
        Log.d(TAG, "setPassWord: = passWord");
        this.passWord = passWord;
    }

    /**
     * Describe the kinds of special objects contained in this Parcelable's
     * marshalled representation.
     *
     * @return a bitmask indicating the set of special object types marshalled
     * by the Parcelable.
     */
    @Override
    public int describeContents() {
        Log.d(TAG, "describeContents: ");
        return 0;
    }

    /**
     * Flatten this object in to a Parcel.
     *
     * @param dest  The Parcel in which the object should be written.
     * @param flags Additional flags about how the object should be written.
     *              May be 0 or {@link #PARCELABLE_WRITE_RETURN_VALUE}.
     */
    @Override
    public void writeToParcel(Parcel dest, int flags) {

        Log.d(TAG, "writeToParcel: = " + flags);
        dest.writeString(userName);
        dest.writeString(passWord);

    }

    public static final Parcelable.Creator<Person> CREATOR = new Creator<Person>() {
        @Override
        public Person createFromParcel(Parcel source) {
            Log.d(TAG, "createFromParcel: ");
            Person person = new Person();
            person.userName = source.readString();
            person.passWord = source.readString();
            Log.d(TAG, "createFromParcel: " + "person.userName = " + person.userName
                    + "\nperson.passWord" + person.passWord);
            LogUtils.d(person);
            return person;
        }

        @Override
        public Person[] newArray(int size) {
            Log.d(TAG, "newArray: size = " + size);
            return new Person[size];
        }
    };
}

2. MainActivity中序列化

 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        bundle_btn = (Button) findViewById(R.id.button);

        bundle_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent();
                intent.setClass(MainActivity.this, SecondActivity.class);
                Person person = new Person("LiuDongBing", "abc.1234");
                Bundle bundle = new Bundle();
                //Parcelable 序列化
                bundle.putParcelable("person", person);
                intent.putExtras(bundle);
                Log.d(TAG, "onClick: startActivity(intent)");
                startActivity(intent);
            }
        });
    }

3. SecondActivity 中反序列化

 protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);

        Intent intent = getIntent();
        Bundle extras = intent.getExtras();
        //Parcelable 反序列化
        Person person = extras.getParcelable("person");
        Log.d(TAG, "onCreate: " + "person.getUserName()" + person.getUserName()
                + "\nperson.getPassWord()" + person.getPassWord());
    }

4. 打印结果

 D/LiuDongBing: Person() called with: userName = [LiuDongBing], passWord = [abc.1234]
 D/LiuDongBing: onClick: startActivity(intent)
 D/LiuDongBing: writeToParcel: = 0
 D/LiuDongBing: createFromParcel: 
 D/LiuDongBing: Person(): 
 D/LiuDongBing: createFromParcel: person.userName = LiuDongBing
                                  person.passWord = abc.1234
 D/LogUtils-/Person$1.createFromParcel(Person.java:90): Person {CREATOR =  {}, TAG = "LiuDongBing", passWord = "abc.1234", userName = "LiuDongBing"} 
 D/LiuDongBing: getUserName: = LiuDongBing
 D/LiuDongBing: getPassWord: =  abc.1234
 D/LiuDongBing: onCreate: person.getUserName()LiuDongBing
                                                                    person.getPassWord()abc.1234

源码连接：https://github.com/JerrryLiu/ParceleableTest