我想用查询中的where子句计算行数

Question

此代码返回总行数。在哪里我想要用户输入username和password的行数。

public boolean logInUser(String un,String pass){
    int row;
    SQLiteDatabase db = getReadableDatabase();
    String query = "SELECT * FROM USER WHERE USERNAME = '" + un + "' AND PASSWORD = '" + pass + "'";
    Cursor c = db.rawQuery(query, null);
    row=c.getCount();
    return row > 0;
}