Should I close the cursor when exiting IntentService?

Question

I'm pretty sure the cursor is destroyed with the IntentService instance, but I just want to be sure there's no memory leak. And if it's a normal practice. I'm querying my custom ContentProvider.

class MyService extends IntentService {
    protected void onHandleIntent(Intent intent) {
        Cursor cursor = getContentResolver().query(
                MyContentProvider.CONTENT_URI, null, null, null, null);
        if (cursor.getCount() == 0) {
            return; // exit the method
        } else {
            cursor.close();
        }
        // some code...
    }
}

Answer 1

Every time you work with a cursor, you should wrap it in try - finally and close it:

Cursor cursor = …;
if (cursor == null)
    return;
try {
    …
} finally {
    cursor.close();
}

This will ensure no memory leaks will occur even when an exception is thrown.

Java 7 brings try-with-resources but only Android API 19+ supports it:

try (Cursor cursor = …)
{
    …
} // Cursor closed automatically