LitePal is an Open Source Android library that allows developers to use SQLite database extremely easy. You can finish most of the database operations without writing even a SQL statement, including create or upgrade tables, crud operations, aggregate functions, etc. The setup of LitePal is quite simple as well, you can integrate it into your project in less than 5 minutes.

Experience the magic right now and have fun!

• Using object-relational mapping (ORM) pattern.
• Almost zero-configuration(only one configuration file with few properties).
• Maintains all tables automatically(e.g. create, alter or drop tables).
• Encapsulated APIs for avoiding writing SQL statements.
• Awesome cluster query function.
• Alternative choice to use SQL still, but easier and better APIs than the originals.
• More for you to explore.

• litepal-1.2.1.jar (library contains *.class files)
• litepal-1.2.1-src.jar (library contains *.class files and *.java files)

• Download the latest jar in the above section. Or browse all versions here to choose one to download.
• Put the jar into libs folder of your Android project.

Edit your build.gradle file and add below dependency:

dependencies {
    compile 'org.litepal.android:core:1.2.1'
}

Create a file in the assets folder of your project and name it as litepal.xml. Then copy the following codes into it.

<?xml version="1.0" encoding="utf-8"?>
<litepal>
    <!--
    	Define the database name of your application. 
    	By default each database name should be end with .db. 
    	If you didn't name your database end with .db, 
    	LitePal would plus the suffix automaticly for you.
    	For example:    
    	<dbname value="demo" ></dbname>
    -->
    <dbname value="demo" ></dbname>

    <!--
    	Define the version of your database. Each time you want 
    	to upgrade your database, the version tag would helps.
    	Modify the models you defined in the mapping tag, and just 
    	make the version value plus one, the upgrade of database
    	will be processed automaticly without concern.
			For example:    
    	<version value="1" ></version>
    -->
    <version value="1" ></version>

    <!--
    	Define your models in the list with mapping tag, LitePal will
    	create tables for each mapping class. The supported fields
    	defined in models will be mapped into columns.
    	For example:    
    	<list>
    		<mapping class="com.test.model.Reader"></mapping>
    		<mapping class="com.test.model.Magazine"></mapping>
    	</list>
    -->
    <list>
    </list>
</litepal>

This is the only configuration file, and the properties are simple.

• dbname configure the database name of project.
• version configure the version of database. Each time you want to upgrade database, plus the value here.
• list configure the mapping classes.

You don't want to pass the Context param all the time. To makes the APIs simple, just configure the LitePalApplication in AndroidManifest.xml as below:

<manifest>
	<application
		android:name="org.litepal.LitePalApplication"
		...
	>
    ...
	</application>
</manifest>

Of course you may have your own Application and has already configured here, like:

<manifest>
	<application
		android:name="com.example.MyOwnApplication"
		...
	>
    ...
	</application>
</manifest>

That's OK. LitePal can still live with that. Just change the inheritance of MyOwnApplication from Application to LitePalApplication, like:

public class MyOwnApplication extends LitePalApplication {
	...
}

Finally, if it still didn't work for you because you have to inherit from another Application. In this case, you can call LitePalApplication.initialize(context) instead of inheritance:

public class MyOwnApplication extends AnotherApplication {

	@Override
	public void onCreate() {
		super.onCreate();
		LitePalApplication.initialize(this);
	}
	...
}

Just make sure to call this method as early as you can. In the onCreate() method of Application will be fine. And always remember to use the application context as parameter. Do not use any intance of activity or service as parameter, or memory leaks might happen.

After setup, you can experience the powerful function now.

Define the models first. For example you have two models, Album and Song. The models can be defined as below:

public class Album extends DataSupport {
	
	private String name;
	
	private float price;
	
	private List<Song> songs = new ArrayList<Song>();

	// generated getters and setters.
	...
}

public class Song extends DataSupport {
	
	private String name;
	
	private int duration;
	
	private Album album;

	// generated getters and setters.
	...
}

Then add these models into the mapping list in litepal.xml:

<list>
    <mapping class="org.litepal.litepalsample.model.Album"></mapping>
    <mapping class="org.litepal.litepalsample.model.Song"></mapping>
</list>

OK! The tables will be generated next time you operate database. For example, gets the SQLiteDatabase with following codes:

SQLiteDatabase db = Connector.getDatabase();

Now the tables will be generated automatically with SQLs like this:

CREATE TABLE album (
	id integer primary key autoincrement,
	price real, 
	name text
);

CREATE TABLE song (
	id integer primary key autoincrement,
	duration integer, 
	name text, 
	album_id integer
);

The saving API is quite object oriented. Each model which inherits from DataSupport would have the save() method directly.

Album album = new Album();
album.setName("album");
album.setPrice(10.99f);
album.save();
Song song1 = new Song();
song1.setName("song1");
song1.setDuration(320);
song1.setAlbum(album);
song1.save();
Song song2 = new Song();
song2.setName("song2");;
song2.setDuration(356);
song2.setAlbum(album);
song2.save();

This will insert album, song1 and song2 into database with relations.

Each model which inherits from DataSupport would also have update() and updateAll() method. You can update a single record with a specified id:

Album albumToUpdate = new Album();
albumToUpdate.setPrice(20.99f); // raise the price
albumToUpdate.update(id);

Or you can update multiple records with a where condition:

Album albumToUpdate = new Album();
albumToUpdate.setPrice(20.99f); // raise the price
albumToUpdate.updateAll("name = ?", "album");

You can delete a single record using the static delete() method in DataSupport:

DataSupport.delete(Song.class, id);

Or delete multiple records using the static deleteAll() method in DataSupport:

DataSupport.deleteAll(Song.class, "duration > ?" , "350");

Find a single record from song table with specified id:

Song song = DataSupport.find(Song.class, id);

Find all records from song table:

List<Song> allSongs = DataSupport.findAll(Song.class);

Constructing complex query with cluster query:

List<Song> songs = DataSupport.where("name like ?", "song%").order("duration").find(Song.class);

• Tony Green - tonygreendev@gmail.com

The sample app has been published onto Google Play for easy access.

Get it on:

If you find any bug when using LitePal, please report here. Thanks for helping us building a better one.

Copyright (C)  Tony Green, LitePal Framework Open Source Project

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.