Serializable使用

android的另一个序列化Serializable比较简单,实现它的接口,然后生成所有成员变量的方法,再生成所有成员变量的getset方法,serializable可以存储对象,所以下面代码传递了一个man对象,然后保存在外置内存卡路径/sdcard/AAAData/output.txt如果没有output.txt文件,打开输出流后会自动生成一个空文件然后写入此空文件,后缀.txt让系统默认用text文本打开.点击按钮打开另一个activity然后反序列化读取output.txt文件.最后不要忘了在配置文件中申明读取文件权限,

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />运行后手机设置也要打开存储权限,再运行一次就好

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        try {
            Man man = new Man("huhx", "123456");
            Person person = new Person(man, "刘力", 21);
            ObjectOutputStream objectOutputStream = new ObjectOutputStream(new FileOutputStream(new File("/sdcard/AAAData/output.txt")));
            objectOutputStream.writeObject("string");
            objectOutputStream.writeObject(person);
            objectOutputStream.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        Button button = findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(MainActivity.this, Main2Activity.class));
            }
        });
    }
}

上面是第一个activity代码

public class Main2Activity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        try {
            ObjectInputStream objectInputStream = new ObjectInputStream(new FileInputStream("/sdcard/AAAData/output.txt"));
            String string = (String) objectInputStream.readObject();
            Person person = (Person) objectInputStream.readObject();
            objectInputStream.close();
            System.out.println(string + ", age: " + person.getAge() + ", man username: " + person.getMan().getUsername());
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

上面是第二个activity代码

public class Person implements Serializable {
    private static final long serialVersionUID = 1L;

    private Man man;
    private String username;
    private  int age;

    public Person() {
        System.out.println("person constru");
    }

    public Person(Man man, String username, int age) {
        this.man = man;
        this.username = username;
        this.age = age;
    }

    public Man getMan() {
        return man;
    }
    public void setMan(Man man) {
        this.man = man;
    }
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }

}

上面是自定义类Person代码

public class Man implements Serializable {
    private static final long serialVersionUID = 1L;

    private String username;
    private String password;

    public Man(String username, String password) {
        this.username = username;
        this.password = password;
    }

    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;
    }

}

上面是自定义对象man代码