Java
Realm is a mobile database: a replacement for SQLite & ORMs

Realm is a mobile database that runs directly inside phones, tablets or wearables. This repository holds the source code for the Java version of Realm, which currently runs only on Android.

Features

• Mobile-first: Realm is the first database built from the ground up to run directly inside phones, tablets and wearables.
• Simple: Data is directly exposed as objects and queryable by code, removing the need for ORM's riddled with performance & maintenance issues. Plus, we've worked hard to keep our API down to very few classes: most of our users pick it up intuitively, getting simple apps up & running in minutes.
• Modern: Realm supports easy thread-safety, relationships & encryption.
• Fast: Realm is faster than even raw SQLite on common operations, while maintaining an extremely rich feature set.

Getting Started

Please see the detailed instructions in our docs to add Realm to your project.

Documentation

Documentation for Realm can be found at realm.io/docs/java. The API reference is located at realm.io/docs/java/api.

Getting Help

• Need help with your code?: Look for previous questions on the #realm tag — or ask a new question. We activtely monitor & answer questions on SO!
• Have a bug to report? Open an issue. If possible, include the version of Realm, a full log, the Realm file, and a project that shows the issue.
• Have a feature request? Open an issue. Tell us what the feature should do, and why you want the feature.
• Sign up for our Community Newsletter to get regular tips, learn about other use-cases and get alerted of blogposts and tutorials about Realm.

Using Snapshots

If you want to test recent bugfixes or features that have not been packaged in an official release yet, you can use a -SNAPSHOT release of the current development version of Realm via Gradle, available on OJO

buildscript {
    repositories {
        maven {
            url 'http://oss.jfrog.org/artifactory/oss-snapshot-local'
        }
    }
    dependencies {
        classpath "io.realm:realm-gradle-plugin:<version>-SNAPSHOT"
    }
}

repositories {
    maven {
        url 'http://oss.jfrog.org/artifactory/oss-snapshot-local'
    }
}

See version.txt for the latest version number.

Building Realm

In case you don't want to use the precompiled version, you can build Realm yourself from source.

Prerequisites:

• Make sure make is available in your $PATH
• Download the JDK 7 or JDK 8 from Oracle and install it.
• Download & install the Android SDK, Android 4.4.2 (API 19), Android 4.4W (API 20) and Android 5.0 (API 21) (for example through Android Studio’s Android SDK Manager)
• Download the Android NDK (= r10e) for OS X or Linux.

• Or you can use Hombrew-versions to install Android NDK for Mac:

  brew tap homebrew/versions
  brew install android-ndk-r10e
  

• Add two environment variables to your profile:

  export ANDROID_HOME=~/Library/Android/sdk
  export NDK_HOME=/usr/local/Cellar/android-ndk-r10e/r10e
  

• If you are using OS X, you'd be better to add following lines to ~/.profile (or ~/.zprofile if the login shell is zsh) in order for Android Studio to see those environment variables.

  launchctl setenv ANDROID_HOME "$ANDROID_HOME"
  launchctl setenv NDK_HOME "$NDK_HOME"
  

• And if you'd like to specify the location to store the archives of Realm's core, set REALM_CORE_DOWNLOAD_DIR environment variable. It enables you to keep core's archive when executing git clean -xfd.

  export REALM_CORE_DOWNLOAD_DIR=~/.realmCore
  

  OS X users should also add following line to ~/.profile (or ~/.zprofile if the login shell is zsh) in order for Android Studio to see this environment variable..

  launchctl setenv REALM_CORE_DOWNLOAD_DIR "$REALM_CORE_DOWNLOAD_DIR"
  

Once you have completed all the pre-requisites building Realm is done with a simple command

./gradlew assemble

That command will generate:

• a jar file for the Realm Gradle plugin
• an aar file for the Realm library
• a jar file for the annotations
• a jar file for the annotations processor

Other Commands

• ./gradlew tasks will show all the available tasks
• ./gradlew javadoc will generate the Javadocs
• ./gradlew monkeyExamples will run the monkey tests on all the examples
• ./gradlew installRealmJava will install the Realm library and plugin to mavenLocal()
• ./gradlew clean -PdontCleanJniFiles will remove all generated files except for JNI related files. This saves recompilation time a lot.
• ./gradlew connectedUnitTests -PbuildTargetABIs=$(adb shell getprop ro.product.cpu.abi) will build JNI files only for the ABI which corresponds to the connected device.

Generating the Javadoc using the command above will report a large number of warnings. The Javadoc is generated, and we will fix the issue in the near future.

Gotchas

The repository is organized in six Gradle projects:

• realm: it contains the actual library (including the JNI layer) and the annotations processor.
• realm-annotations: it contains the annotations defined by Realm.
• realm-transformer: it contains the bytecode transformer.
• gradle-plugin: it contains the Gradle plugin.
• examples: it contains the example projects. This project directly depends on gradle-plugin which adds a dependency to the artifacts produced by realm.
• The root folder is another Gradle project and all it does is orchestrating the other jobs

This means that ./gradlew clean and ./gradlew cleanExamples will fail if assembleExamples has not been executed first. Note that IntelliJ does not support multiple projects in the same window so each sub-project must be opened in its own window.

Contributing

See CONTRIBUTING.md for more details!

License

Realm Java is published under the Apache 2.0 license. The underlying core is available under the Realm Core Binary License while we work to open-source it under the Apache 2.0 license.

This product is not being made available to any person located in Cuba, Iran, North Korea, Sudan, Syria or the Crimea region, or to any other person that is not eligible to receive the product under U.S. law.

Feedback

If you use Realm and are happy with it, all we ask is that you please consider sending out a tweet mentioning @realm, announce your app on our mailing-list, or email help@realm.io to let us know about it!

And if you don't like it, please let us know what you would like improved, so we can fix it!