在 SQLite 數據庫中插入 ArrayList

Question

我有一個來自 API 的 ArrayList，我的 POJO（Plain Old Java Object）具有所需的 getter 和 setter。

@SerializedName("staff")
@Expose
private List<String> staff = new ArrayList<String>();
@SerializedName("departments")
@Expose
private List<String> departments = new ArrayList<String>();

我想將員工和部門添加到SQLite Table 中。 我現有的表具有其余的字符串值。 但我無法將ArrayList添加到表中。

public static final String CREATE_TABLE_QUERY = "CREATE TABLE " + TABLE_NAME + "" +
            " (" + ID + " TEXT PRIMARY KEY not null, " +
            //need to change product id into String or TEXT
            CLIENTS_NAME + " TEXT not null," +
            CLIENTS_ADDRESS1 + " TEXT not null," +
            CLIENTS_ADDRESS2 + " TEXT not null," +
            CLIENTS_ADDRESS3 + " TEXT not null," +
            CLIENTS_ADDRESS4 + " TEXT not null," +
            TYPE + " TEXT not null," +
            CLIENTS_CONTACT + " TEXT not null)" ;

我如何添加 Arraylist ？ 我試過這個，但它不工作。 任何鏈接或提示將不勝感激。

這是將其余的字符串值插入到數據庫中。注意，我還沒有將人員添加到數據庫表中，因為我不知道如何在表中插入一個 Arraylist。

 public void addProducts(Clients_POJO products) {
    //CRUD , adding Products

    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(Constants.ClientsDATABASE.ID, products.getId());
    values.put(Constants.ClientsDATABASE.CLIENTS_NAME, products.getName());
    values.put(Constants.ClientsDATABASE.CLIENTS_ADDRESS1, products.getAddress1());
    values.put(Constants.ClientsDATABASE.CLIENTS_ADDRESS2, products.getAddress2());
    values.put(Constants.ClientsDATABASE.CLIENTS_ADDRESS3, products.getAddress3());
    values.put(Constants.ClientsDATABASE.CLIENTS_ADDRESS4, products.getAddress4());
    values.put(Constants.ClientsDATABASE.TYPE, products.getType());
    values.put(Constants.ClientsDATABASE.CLIENTS_CONTACT, products.getContact());

    try {

        db.insert(Constants.ClientsDATABASE.TABLE_NAME, null, values);
    } catch (Exception e) {
        Log.d(TAG, e.getMessage());
    }

Answer 1

我找到了沒有使用 GSON 轉換的解決方案。 讓部門的 POJO 值是一個 ArrayList。

@SerializedName("departments")
@Expose
private List<String> departments = new ArrayList<String>();

為了創建數據庫，我們將列作為字符串存儲在表中。

public static final String INPUT_DEPARTMENTS = "departments";
public static final String CREATE_TABLE_QUERY = "CREATE TABLE " + TABLE_NAME + "" +
            " (" + ID + " TEXT PRIMARY KEY not null, " +
            INPUT_DEPARTMENTS + " TEXT not null)" ;

現在在 SQLite 數據庫中存儲和檢索數據時。存儲 ->

public void addProducts(Clients_POJO products) {
    //CRUD , adding Products
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put(Constants.ClientsDATABASE.INPUT_DEPARTMENTS, String.valueOf(products.getDepartments()));
    try {

        db.insert(Constants.ClientsDATABASE.TABLE_NAME, null, values);
    } catch (Exception e) {
        Log.d(TAG, e.getMessage());
    }

為了檢索數據，我們將其轉換回一個數組列表以將值存儲在 POJO 中。

SQLiteDatabase db = this.getWritableDatabase();
    final ProductFetchListener mListener = listener;
    Cursor cursor = db.rawQuery(Constants.ClientsDATABASE.GET_PRODUCTS_QUERY,null);
    final List<Clients_POJO> productsListDB = new ArrayList<>();
    if (cursor.getCount() > 0) {
        if (cursor.moveToFirst()) {
            do {
                Clients_POJO products = new Clients_POJO();
                products.setFromDatabase(true);

現在我們將其轉換為一個數組列表。

String s =  cursor.getString(cursor.getColumnIndex(Constants.ClientsDATABASE.INPUT_DEPARTMENTS));
List<String> myList = new ArrayList<String>(Arrays.asList(s.split(",")));
products.setDepartments(myList);