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Atlas Device SDKs

Install Realm - Java SDK

On this page

  • Overview
  • Prerequisites
  • Installation
  • Project Gradle Configuration
  • Application Module Gradle Configuration
  • Enable Atlas Device Sync
  • Supported Platforms

Note

Java SDK in Maintenance Mode

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.

Note

New Java SDK apps cannot use RealmAny

New App Services Apps will not be able to synchronize data models with properties of type RealmAny.

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. For example, you can add Atlas Device Sync's Data Ingest feature to your app using the Kotlin SDK while continuing to use Java for everything else.

Prerequisites

Installation

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

Note

ProGuard

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

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.

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
}

  • Add the io.realm:realm-gradle-plugin dependency to the buildscript.dependencies block.

  • Add the mavenCentral() repository to the allprojects.repositories block.

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:

  • Apply the kotlin-kapt plugin if your application uses Kotlin

  • Beneath the plugins block, apply the realm-android plugin.

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'
}

  • Apply the kotlin-kapt plugin if your application uses Kotlin

  • Apply the realm-android plugin

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.

Enable Atlas Device Sync

To use Atlas Device Sync in your application, create a realm block in your application module build.gradle. Within this block, set syncEnabled to true.

realm {
    syncEnabled = true
}

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

Next

Welcome to the Atlas Device SDK Docs