MyServiceIntent.java

package monakhv.android.samlib.service;

import android.app.IntentService;
import android.content.Context;
import com.j256.ormlite.android.apptools.OpenHelperManager;
import monakhv.android.samlib.SamlibApplication;
import monakhv.android.samlib.data.DataExportImport;
import monakhv.android.samlib.data.SettingsHelper;
import monakhv.android.samlib.sql.DatabaseHelper;
import monakhv.samlib.db.AuthorController;


/*
 * Copyright 2015  Dmitry Monakhov
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * 02.07.15.
 */
public abstract class MyServiceIntent extends IntentService {
    private volatile DatabaseHelper helper;
    private volatile boolean created = false;
    private volatile boolean destroyed = false;

    private SamlibApplication mSamlibApplication;
    /**
     * Creates an IntentService.  Invoked by your subclass's constructor.
     *
     * @param name Used to name the worker thread, important only for debugging.
     */
    public MyServiceIntent(String name) {
        super(name);
    }

    public DatabaseHelper getHelper() {
        if (helper == null) {
            if (!created) {
                throw new IllegalStateException("A call has not been made to onCreate() yet so the helper is null");
            } else if (destroyed) {
                throw new IllegalStateException(
                        "A call to onDestroy has already been made and the helper cannot be used after that point");
            } else {
                throw new IllegalStateException("Helper is null for some unknown reason");
            }
        } else {
            return helper;
        }
    }

     @Override
    public void onCreate() {
        if (helper == null) {
			helper = getHelperInternal(this);
			created = true;
		}
        super.onCreate();
        mSamlibApplication= (SamlibApplication) getApplication();
    }

    public SettingsHelper getSettingsHelper(){
        return mSamlibApplication.getSettingsHelper();
    }

    public DataExportImport getDataExportImport(){
        return mSamlibApplication.getDataExportImport();
    }

    public AuthorController getAuthorController(){
        return mSamlibApplication.getDatabaseComponent(getHelper()).getAuthorController();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        releaseHelper(helper);
		destroyed = true;
        mSamlibApplication.releaseDatabaseComponent();
        mSamlibApplication.releaseServiceComponent();
    }

/**
	 * This is called internally by the class to populate the helper object instance. This should not be called directly
	 * by client code unless you know what you are doing. Use {@link #getHelper()} to get a helper instance. If you are
	 * managing your own helper creation, override this method to supply this activity with a helper instance.
	 *
	 * <p>
	 * <b> NOTE: </b> I
	 */
	protected DatabaseHelper getHelperInternal(Context context) {
		@SuppressWarnings({ "unchecked", "deprecation" })
        DatabaseHelper newHelper = (DatabaseHelper) OpenHelperManager.getHelper(context,DatabaseHelper.class);
		return newHelper;
	}
    /**
	 * Release the helper instance created in {@link #getHelperInternal(Context)}. You most likely will not need to call
	 * this directly since {@link #onDestroy()} does it for you.
	 *
	 * <p>
	 * <b> NOTE: </b> If you override this method, you most likely will need to override the
	 * {@link #getHelperInternal(Context)} method as well.
	 * </p>
	 */
	protected void releaseHelper(DatabaseHelper helper) {
		OpenHelperManager.releaseHelper();
		this.helper = null;
	}

}