Question

I’m using a custom Database class in my code to manage my database and handle transactions. Whenever I instantiate it, I pass the application context to it’s constructor. Reading up on the articles at the Android developer site makes me wonder if I’m doing something that could cause a huge memory leak in my application. Simplified, my code looks like this, first off an activity:

    public class MyActivity extends Activity
    {

        @Override
        protected void onCreate(Bundle savedInstanceState)
        {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.somelayout);

            Database db = new Database(getApplicationContext());
        }

    }

And my database class (in a seperate file) looks like this:

public class Database
{

    Context context;

    public Database(Context context)
    {
        this.context = context;
    }

    public DatabaseHelper extends SQLiteOpenHelper
    {
        // Pass the context to the constructor etc etc.
    }

}

The code might have bugs, I wrote it quickly in notepad. Anyway, this got me worried that the db object keeps the context when the user navigates away from the activity, thus uneccesarily spending a huge amount of resources. If this is indeed the case, how can I avoid this? Is there a way to destroy and object when it is no longer needed?

Answer 1

The object referenced by db is eligible for garbage collection as soon as onCreate finishes. So there is no problem here.

If you made db or Database.context into a static field, that’s when you should start to worry.