android ormlite登录注册的例子(9)

     
    private Dao<UsersEntity, Integer> userDao = null; 
 
    public DataHelper(Context context) 
    { 
        super(context, DATABASE_NAME, null, DATABASE_VERSION); 
    } 
 
    @Override 
    public void onCreate(SQLiteDatabase db, ConnectionSource connectionSource) 
    { 
        try 
        { 
            TableUtils.createTable(connectionSource, UsersEntity.class);  
        } catch (SQLException e) 
        { 
            Log.e(DataHelper.class.getName(), "创建数据库失败", e); 
            e.printStackTrace(); 
        } 
    } 
 
    @Override 
    public void onUpgrade(SQLiteDatabase db, ConnectionSource connectionSource, 
            int arg2, int arg3) 
    { 
        try 
        { 
            TableUtils.dropTable(connectionSource, UsersEntity.class, true); 
            onCreate(db, connectionSource); 
        } catch (SQLException e) 
        { 
            Log.e(DataHelper.class.getName(), "更新数据库失败", e); 
            e.printStackTrace(); 
        } 
    } 
 
    @Override 
    public void close() 
    { 
        super.close(); 
        userDao = null; 
    } 
 
    public Dao<UsersEntity, Integer> getUserDataDao() throws SQLException 
    { 
        if (userDao == null) 
        {