Install Realm - Java SDK

Note: The Java SDK is in best-effort maintenance mode and **no longer receives new development or non-critical bug fixes. To develop your app with new features, use the Kotlin SDK. You can use the Java SDK with the Kotlin SDK in the same project.

Learn more about how to Migrate from the Java SDK to the Kotlin SDK.

Overview

This page details how to install Realm using the Java SDK in your project and get started.

You can use multiple SDKs in your project. Because the Java SDK is no longer receiving new development, this is useful if you want to use new features in your app.

Prerequisites

Android Studio version 1.5.1 or higher.
Java Development Kit (JDK) 11 or higher.
An emulated or hardware Android device for testing.
Android API Level 16 or higher (Android 4.1 and above).

Installation

Realm only supports the Gradle build system. Follow these steps to add the Realm Java SDK to your project.

Note: Because Realm provides a ProGuard configuration as part of the Realm library, you do not need to add any Realm-specific rules to your ProGuard configuration.

Project Gradle Configuration

To add local realm to your application, make the following changes to your project-level Gradle build file, typically found at <project>/build.gradle:

Gradle Plugin

Tip: The Java SDK does not yet support the Gradle Plugin syntax. Fortunately, you can still add the SDK to projects that use this syntax.

Add a buildscript block that contains a repositories block and a dependencies block.
Add the mavenCentral() repository to the buildscript.repositories block.
Add the io.realm:realm-gradle-plugin dependency to the buildscript.dependencies block.

groovy

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath "io.realm:realm-gradle-plugin:10.18.0"
    }
}

plugins {
    id 'com.android.application' version '7.1.2' apply false
    id 'com.android.library' version '7.1.2' apply false
    id 'org.jetbrains.kotlin.android' version '1.6.10' apply false
    id "org.jetbrains.kotlin.kapt" version "1.6.20" apply false
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

Gradle Legacy

Add the io.realm:realm-gradle-plugin dependency to the buildscript.dependencies block.
Add the mavenCentral() repository to the allprojects.repositories block.

groovy

buildscript {
    repositories {
        google()
    }
    dependencies {
        classpath "com.android.tools.build:gradle:3.5.1"
        classpath "io.realm:realm-gradle-plugin:10.18.0"
    }
}

allprojects {
    repositories {
        google()
        mavenCentral()
    }
    dependencies {
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

Application Module Gradle Configuration

Then, make the following changes to your application-level Gradle build file, typically found at <project>/app/build.gradle:

Gradle Plugin

Apply the kotlin-kapt plugin if your application uses Kotlin
Beneath the plugins block, apply the realm-android plugin.

groovy

plugins {
    id 'com.android.application'
    id 'org.jetbrains.kotlin.android'
    id 'org.jetbrains.kotlin.kapt'
}

apply plugin: "realm-android"

android {
    compileSdk 31
    defaultConfig {
        applicationId "com.mongodb.example-realm-application"
        minSdk 28
        targetSdk 31
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_11
        targetCompatibility JavaVersion.VERSION_11
    }
    kotlinOptions {
        jvmTarget = '11'
    }
}

dependencies {
    implementation 'io.realm:realm-gradle-plugin:10.10.1'
    implementation 'androidx.core:core-ktx:1.7.0'
    implementation 'androidx.appcompat:appcompat:1.4.1'
    implementation 'com.google.android.material:material:1.5.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.3'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
}

Gradle Legacy

Apply the kotlin-kapt plugin if your application uses Kotlin
Apply the realm-android plugin

groovy

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-kapt'
apply plugin: 'realm-android'

android {
    compileSdkVersion 31
    buildToolsVersion "29.0.2"
    defaultConfig {
        applicationId "com.mongodb.example-realm-application"
        minSdkVersion 28
        targetSdkVersion 31
    }
    compileOptions {
        sourceCompatibility 1.11
        targetCompatibility 1.11
    }
    kotlinOptions {
        jvmTarget = '11'
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    implementation "androidx.appcompat:appcompat:1.1.0"
    implementation "androidx.core:core-ktx:1.2.0"
}

After updating the build.gradle files, resolve the dependencies by clicking File > Sync Project with Gradle Files.

Supported Platforms

Realm's Java SDK enables you to build apps for the following platforms:

Android
Wear OS
Android Automotive OS
Android TV
Android Things