java 클래스의 ArrayList 파일 만들기

Question

누군가의 생일이 언제인지 알려주는 Android 앱을 만들고 있습니다.

이제 이름과 해당 날짜를 추가 할 수있게되었습니다. 하지만 현재 내가 갇혀있는 곳은 저축 부분입니다. 이미 몇 가지 해결책을 찾아 보았지만 내 필요에 이식 할 수 없었습니다. ArrayList이기 때문에 간단한 문자열이 아니기 때문에 직렬화 할 수 없습니다 (맞으면?) 따라서 저장되지 않습니다. 이런 종류의 데이터를 저장하는 다른 방법이 있습니까?

Item.java : 여기

내 코드입니다

public class Item implements Serializable{ 
    private String name; 
    private String date; 

    public Item(String name, String date){ 
     this.name = name; 
     this.date = date; 
    } 

    public String getName(){ 
     return name; 
    } 

    public String getDate(){ 
     return date; 
    } 

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

    public void setDate(String date){ 
     this.date = date; 
    } 
} 

MainActivity.java :

자바 ArrayLists 직렬화 또는 직렬화 복원 아무 문제가 없습니다

public class MainActivity extends AppCompatActivity { 

RecyclerView recyclerView; 
static RecyclerviewAdapter adapter; 

static ArrayList<Item> itemList = new ArrayList<>(); 

private static String nameText; 
private static String birthString; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 

    setContentView(R.layout.activity_main); 

    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); 
    setSupportActionBar(toolbar); 

    recyclerView = (RecyclerView) findViewById(R.id.recyclerview); 

    LinearLayoutManager llm = new LinearLayoutManager(this); 
    llm.setOrientation(LinearLayoutManager.VERTICAL); 

    recyclerView.setLayoutManager(llm); 
    recyclerView.setItemAnimator(new DefaultItemAnimator()); 

    adapter = new RecyclerviewAdapter(itemList); 
    recyclerView.setAdapter(adapter); 

    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab); 
    fab.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View view) { 
      AddBirthday(); 
     } 
    }); 
} 

@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    // Inflate the menu; this adds items to the action bar if it is present. 
    getMenuInflater().inflate(R.menu.menu_main, menu); 
    return true; 
} 

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    // Handle action bar item clicks here. The action bar will 
    // automatically handle clicks on the Home/Up button, so long 
    // as you specify a parent activity in AndroidManifest.xml. 
    int id = item.getItemId(); 

    //noinspection SimplifiableIfStatement 
    if (id == R.id.action_settings) { 
     return true; 
    } 

    return super.onOptionsItemSelected(item); 
} 

public static class DatePickerFragment extends DialogFragment 
     implements DatePickerDialog.OnDateSetListener { 

    @Override 
    public Dialog onCreateDialog(Bundle savedInstanceState) { 
     // Use the current date as the default date in the picker 
     final Calendar c = Calendar.getInstance(); 
     int year = c.get(Calendar.YEAR); 
     int month = c.get(Calendar.MONTH); 
     int day = c.get(Calendar.DAY_OF_MONTH); 

     // Create a new instance of DatePickerDialog and return it 
     return new DatePickerDialog(getActivity(), this, year, month, day); 
    } 

    public void onDateSet(DatePicker view, int year, int month, int day) { 
     // Do something with the date chosen by the user 
     month++; 
     birthString = day + "-" + month + "-" + year; 
     itemList.add(new Item(nameText, birthString)); 
     adapter.notifyDataSetChanged(); 
     saveArrayList(getContext(), itemList); 
    } 
} 

private void AddBirthday() { 
    AlertDialog.Builder builder = new AlertDialog.Builder(this); 
    builder.setTitle("Name"); 

    final EditText input = new EditText(this); 
    input.setInputType(InputType.TYPE_CLASS_TEXT); 
    builder.setView(input); 
    builder.setPositiveButton("OK", new DialogInterface.OnClickListener() { 
     @Override 
     public void onClick(DialogInterface dialog, int which) { 
      nameText = input.getText().toString(); 

      DialogFragment newFragment = new DatePickerFragment(); 
      newFragment.show(getSupportFragmentManager(), "datePicker"); 
     } 
    }); 
    builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() { 
     @Override 
     public void onClick(DialogInterface dialog, int which) { 
      dialog.cancel(); 
     } 
    }); 
    builder.show(); 
} 

public static void saveArrayList(Context c, ArrayList<Item> arrayList) { 

} 
} 

Answer 1

:

List<Item> list = new ArrayList<>(); 

    list.add(new Item("A", "2006")); 
    list.add(new Item("B", "2016")); 


    // Serialize 
    FileOutputStream fos = context.openFileOutput("list.ser", Context.MODE_PRIVATE); 
    ObjectOutputStream os = new ObjectOutputStream(fos); 
    os.writeObject(list); 
    os.close(); 
    fos.close(); 


    // Deserialize 

    FileInputStream fileIn = context.openFileInput("list.ser"); 
    ObjectInputStream in = new ObjectInputStream(fileIn); 
    list = (List<Item>) in.readObject(); 
    in.close(); 
    fileIn.close(); 

    // Implement toString() in Item 
    System.out.println(list); 

가