Android保存Serializable数据到本地

1.定义一个Student类，实现Serializable接口

public class Student implements Serializable {    private Integer id;    private String name;    //注意定义此字段    public static final long serialVersionUID = 9527L;    public Student() {        super();    }    public Student(Integer id, String name) {        super();        this.id = id;        this.name = name;    }    public Integer getId() {        return id;    }    public void setId(Integer id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    @Override    public String toString() {        return "Student [id=" + id + ", name=" + name + "]";    }}

2.模拟数据进行存储并读取，在屏幕上显示。

public class MainActivity extends AppCompatActivity {    private TextView tvShow;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        tvShow=(TextView)findViewById(R.id.tvShow);        testSerializable();    }    private void testSerializable() {        FileOutputStream fileOutputStream=null;        ObjectOutputStream objectOutputStream =null;        FileInputStream fileInputStream = null;        ObjectInputStream objectInputStream = null;        StringBuffer sb=new StringBuffer();        ArrayList studentsArrayList = new ArrayList();        Student student = null;        for (int i = 1; i < 5; i++) {            student = new Student(i, "人物" + i);            studentsArrayList.add(student);        }        try {            //存入数据            File file = new File(Environment.getExternalStorageDirectory().toString()                    + File.separator +"Test"+File.separator + "data.txt");            if (!file.getParentFile().exists()) {                file.getParentFile().mkdirs();            }            if (!file.exists()) {                file.createNewFile();            }            fileOutputStream= new FileOutputStream(file.toString());            objectOutputStream= new ObjectOutputStream(fileOutputStream);            objectOutputStream.writeObject(studentsArrayList);            //取出数据            fileInputStream = new FileInputStream(file.toString());            objectInputStream = new ObjectInputStream(fileInputStream);            ArrayList savedArrayList =(ArrayList) objectInputStream.readObject();            for (int i = 0; i < savedArrayList.size(); i++) {                //System.out.println("取出的数据:" + savedArrayList.get(i).toString());                sb.append("取出的数据:"+savedArrayList.get(i).toString()+"\r\n");            }            tvShow.setText(sb.toString());        } catch (Exception e) {            // TODO: handle exception        }finally{            if (objectOutputStream!=null) {                try {                    objectOutputStream.close();                } catch (IOException e) {                    e.printStackTrace();                }            }            if (fileOutputStream!=null) {                try {                    fileOutputStream.close();                } catch (IOException e) {                    e.printStackTrace();                }            }            if (objectInputStream!=null) {                try {                    objectInputStream.close();                } catch (IOException e) {                    e.printStackTrace();                }            }            if (fileInputStream!=null) {                try {                    fileInputStream.close();                } catch (IOException e) {                    e.printStackTrace();                }            }        }    }}

3.添加权限

 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

4.效果如下图所示。

Android保存Serializable数据到本地_第1张图片

Android保存Serializable数据到本地_第2张图片

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