Android小记-SQLiteOpenHelper正确使用避免leak

Posted 2022-11-27 everlastxgb

在开发中我们经常会使用到SQLite，android提供了一个叫SQLiteOpenHelper的帮助类，但在使用的时候，如果不谨慎，经常会出现泄漏问题。建议采用单例确保database实例只有一个。

public class DatabaseHelper extends SQLiteOpenHelper  

  private static DatabaseHelper sInstance;

  private static final String DATABASE_NAME = "database_name";
  private static final String DATABASE_TABLE = "table_name";
  private static final int DATABASE_VERSION = 1;

  public static synchronized DatabaseHelper getInstance(Context context) 

    // Use the application context, which will ensure that you 
    // don't accidentally leak an Activity's context.
    // See this article for more information: http://bit.ly/6LRzfx
    if (sInstance == null) 
      sInstance = new DatabaseHelper(context.getApplicationContext());
    
    return sInstance;
  

  /**
   * Constructor should be private to prevent direct instantiation.
   * make call to static method "getInstance()" instead.
   */
  private DatabaseHelper(Context context) 
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
  


// 下面方法用于校验某个database
private static boolean checkDatabase() 
    SQLiteDatabase checkDB = null;

    try 
        String myPath = "YourDatabasePath";
        checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
        checkDB.close();

     catch (Exception ex) 

    

    return checkDB != null ? true : false;