TaRSySAndroidORMKotlin2 (Yet Another Android ORM v2)

Why I created this ORM if there are already many others?

I created this ORM for one simple reason … I could not find one that would cover all my needs …

I was looking for a ORM that was easy to deploy, powerful, and without any interaction by the developer at the time of making changes to the persistent entities. Previously, I developed an ORM for Java (TaRSySAndroidORM), but I saw that there was not one developed with Kotlin and for Kotlin to cover my needs…

How it works?

The integration with your project is very simple, let’s see it in somesteps:

Add a reference in your build.gradle.

  implementation 'com.github.tarsys.android:kotlin-orm2:2.0.0.2'

Add some meta tags to your Manifest.xml

 <application
     android:allowBackup="true"
     android:icon="@mipmap/ic_launcher"
     android:label="@string/app_name"
     android:supportsRtl="true"
     android:theme="@style/AppTheme" >

     <meta-data android:name="IS_EXTERNALSTORAGE" android:value="true" />
     <meta-data android:name="DATABASE_DIRECTORY" android:value="ExampleTaRSySORM" />
     <meta-data android:name="DATABASE_NAME" android:value="exampletarsysorm.db" />
     <meta-data android:name="ENTITY_PACKAGES" android:value="com.tarsys.examplekotlinorm.entities" />
     <meta-data android:name="DB_STRING_DEFAULT_LENGTH" android:value="500" />

     <activity android:name=".MainActivity" >
         <intent-filter>
             <action android:name="android.intent.action.MAIN" />
             <category android:name="android.intent.category.LAUNCHER" />
         </intent-filter>
     </activity>
 </application>

Add in your Launcher activity this code:

 if (SgbdEngine.initialize(this)){
   // TODO: Do some stuff
 }else{
   // if something wrong, do other stuff
 }

Create the entity classes (All classes must implement the IOrmEntity Interface):

 package com.tarsys.examplekotlinorm.entities
  
 @DBEntity
 class Car: IOrmEntity {
   @TableField(PrimaryKey = true)
   var Id: Int = 0
   @TableField
   var CarPlate: String = AndroidSupport.EmptyString
   @TableField
   var Brand: String = AndroidSupport.EmptyString
   @TableField
   var Model: String = AndroidSupport.EmptyString
 }
  
 @DBEntity
 class Person: IOrmEntity {
   @TableField(PrimaryKey = true)
   var Id: Int = 0
   @TableField(DataTypeLength = 60)
   var FirstName: String = AndroidSupport.EmptyString
   @TableField(DataTypeLength = 60)
   var LastName: String = AndroidSupport.EmptyString
   @TableField(DataType = DBDataType.EntityListDataType, EntityClass = Car::class, CascadeDelete = true)
   var Cars: ArrayList<Car> = arrayListOf()
 }

Use it!

 // Create some Person entities
 val person1 = Person()
 val person2 = Person()
    
 // Create some Car entities
 val car1 = Car()
 val car2 = Car()
 val car3 = Car()
    
 car1.CarPlate = "1234BNZ"
 car1.Brand = "Mazda"
 car1.Model = "2"
    
 car2.CarPlate = "5432DSJ"
 car2.Brand = "Toyota"
 car2.Model = "Avensis"
    
 car3.CarPlate = "4356KDD"
 car3.Brand = "Mazda"
 car3.Model = "CX-5"
    
 person1.FirstName = "Jane"
 person1.LastName = "Nobody"
 person1.Cars.addAll(arrayListOf(car1, car2))
    
 person2.FirstName = "John"
 person2.LastName = "Nobody"
 person2.Cars.add(car3)
    
 // If we don't persist car entities, when we save persons, recursivelly save the cars too
 if (person1.save() && person2.save()){
   // because we have persons, we can filter using lambda or primary key loads...
   val personPk = Person()
   personPk.Id = 1 // We suppose person 1 has id = 1
   if (personPk.read()){
     // Successfully readed person...
              
     // we can delete entities...
     if (personPk.delete()){
       // if we have deleted the entity...
     }
   }
      
   // we can filter first level entities (don't filter sub entities, like arrays...)
   val fPersons = Person::class.filter { x -> x.LastName == "Nobody"} // returns a soft loaded entities (subentities, only with ids)
   val fullPersons = Person::class.fullFilter { x -> x.LastName == "Nobody"} // returns a full loaded entities      
 }

TaRSySAndroidKotlinORM2