Implement ContentProvider

public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
		String sortOrder){
	SQLiteDatabase database = mDbHelper.getReadableDatabase();

	Cursor cursor;

	int match = sUriMatcher.match(uri);
	switch(match){
		case PETS:
			// 
			break;
		case PET_ID:
			selection = PetEntry._ID + "=?";
			selectionArgs = new String[] { String.valueOf(ContentUris.parseId(uri))};
			cursor = database.query(PetEntry.TABLE_NAME, projection, selection, selectionArgs,
				null, null, sortOrder);
			break;
		default:
			throw new IllegalArgumentException("Cannot query unknown URI " + uri);
	}
	return cursor;
}

public class PetProvider extends ContentProvider {

	@Override
	public Uri insert(Uri uri, ContentValues contentValues){
		final int match = sUriMatcher.match(uri);
		switch (match){
			case PETS:
				return insertPet(uri, contentValues);
			default:
				throw new IllegalArgumentException("Insertion is not supported for " + uri);
		}
	}

	private Uri insertPet(Uri uri, ContentValues values){
		return ContentUris.withAppendedId(uri, id):
	}
}

private Uri insertPet(Uri uri, ContentValues values){
	String name = values.getAsString(PetEntry.COLUMN_PET_NAME);
	if (name == null){
		throw new IllegalArgumentException("Pet requires a name");
	}

	SQLiteDatabase database = mDbHelper.getWritableDatabse();

	long id = database.insert(PetEntry.TABLE_NAME, null, values);
	if (id == -1){
		Log.e(LOG_TAG, "Failed to insert row for " + uri);
		return null;
	}

	return ContentUris.withAppendedId(uri, id);
}