NullAway

Tech stack & purpose

NullAway is a static analysis tool built by Uber that eliminates NullPointerExceptions in Java code through annotation-based null checking. The tool works by requiring developers to add `@Nullable` annotations to fields, method parameters, and return values that may be null, then performs type-based local checks to ensure dereferenced pointers cannot be null. Built as a plugin to Error Prone, NullAway is designed for practical use with low build-time overhead (typically under 10%) and supports Java projects using Gradle, Android development, and various annotation libraries including JSpecify, AndroidX, and JetBrains annotations.

Community & reference links

• Error Prone
• Error Prone
• here
• Error Prone documentation
• Checker Framework
• join the NullAway Discord server
• Eradicate
• AutoValue
• Guava
• annotated JSpecify JDK
• Gradle Error Prone plugin
• no longer support Android
• Gradle NullAway plugin
• sample app `build.gradle` file
• open a GitHub issue
• here
• our detailed guide
• the configuration docs
• the docs
• the wiki docs on JSpecify support
• Dagger
• JSpecify
• WALA

Languages

Contributors (top 30 of 82)

• Manu Sridharan705 commits
• Lázaro Clapp149 commits
• Lazaro Clapp112 commits
• Yuxin Wang61 commits
• Nima Karimipour28 commits
• shubham ugare16 commits
• Md Armughanuddin16 commits
• Christopher Lambert15 commits
• Abhijit Kulkarni13 commits
• Seemanta Saha12 commits
• Raghavan Raman10 commits
• Yeahn Kim8 commits
• Dhruv Agrawal8 commits
• Zac Sweers7 commits
• Subarno5 commits
• Jochen Schalanda4 commits
• Nikita Dinkar Aware3 commits
• David Gang3 commits
• Michael Ernst3 commits
• NikitaAware3 commits
• Carter Kozak3 commits
• Thomas Broyer2 commits
• Gautam Korlam2 commits
• Salman Chishti2 commits
• haewiful2 commits
• Ullrich Hafner2 commits
• Ankit Yadav2 commits
• Yosuke Kobayashi2 commits
• Daniel Widdis2 commits
• Akshay Utture2 commits