NullAway initial commit

.github/ISSUE_TEMPLATE.md

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+Thanks for using NullAway. Before you create an issue, please consider the following points:
+
+  - [ ] If you think you found a bug, please include a code sample that reproduces the problem. A test case that reproduces the issue is preferred. A stack trace alone is ok but may not contain enough context for us to address the issue.
+
+  - [ ] Please include the library version number, including the minor and patch version, in the issue text.

.github/PULL_REQUEST_TEMPLATE.md

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+Thank you for contributing to NullAway. Before pressing the "Create Pull Request" button, please provide the following:
+
+  - [ ] A description about what and why you are contributing, even if it's trivial.
+
+  - [ ] The issue number(s) or PR number(s) in the description if you are contributing in response to those.
+
+  - [ ] If applicable, unit tests.

.gitignore

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+###OSX###
+
+.DS_Store
+.AppleDouble
+.LSOverride
+
+# Icon must ends with two \r.
+Icon
+
+
+# Thumbnails
+._*
+
+# Files that might appear on external disk
+.Spotlight-V100
+.Trashes
+
+
+###Linux###
+
+*~
+
+# KDE directory preferences
+.directory
+
+
+###Android###
+
+# Built application files
+*.apk
+*.ap_
+
+# Files for ART and Dalvik VM
+*.dex
+
+# Java class files
+*.class
+
+# Generated files
+bin/
+gen/
+
+# Gradle files
+.gradle/
+.gradletasknamecache
+build/
+
+# Local configuration file (sdk path, etc)
+local.properties
+
+# Proguard folder generated by Eclipse
+proguard/
+
+# Lint
+lint-report.html
+lint-report_files/
+lint_result.txt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.war
+*.ear
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+
+
+###IntelliJ###
+
+*.iml
+*.ipr
+*.iws
+.idea/
+
+
+###Eclipse###
+
+*.pydevproject
+.metadata
+tmp/
+*.tmp
+*.bak
+*.swp
+*~.nib
+.settings/
+.loadpath
+
+# External tool builders
+.externalToolBuilders/
+
+# Locally stored "Eclipse launch configurations"
+*.launch
+
+# CDT-specific
+.cproject
+
+# PDT-specific
+.buildpath
+
+# sbteclipse plugin
+.target
+
+# TeXlipse plugin
+.texlipse
+
+# kotlin
+annotations/

.travis.yml

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+language: java
+
+jdk:
+  - oraclejdk8
+
+script:
+  - ./gradlew build
+
+
+
+notifications:
+  email: false
+
+sudo: false
+
+cache:
+  directories:
+    - $HOME/.gradle

CHANGELOG.md

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+Changelog
+=========
+
+Version 0.1.0
+----------------------------
+
+* Initial release

CONTRIBUTING.md

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+Contributing to Uber's Android Template
+=======================
+
+Uber welcomes contributions of all kinds and sizes. This includes everything from from simple bug reports to large features.
+
+Workflow
+--------
+
+We love GitHub issues!
+
+For small feature requests, an issue first proposing it for discussion or demo implementation in a PR suffice.
+
+For big features, please open an issue so that we can agree on the direction, and hopefully avoid investing a lot of time on a feature that might need reworking.
+
+Small pull requests for things like typos, bug fixes, etc are always welcome.
+
+DOs and DON'Ts
+--------------
+
+* DO follow our [coding style](https://github.com/uber/java-code-styles) 
+* DO include tests when adding new features. When fixing bugs, start with adding a test that highlights how the current behavior is broken.
+* DO keep the discussions focused. When a new or related topic comes up it's often better to create new issue than to side track the discussion.
+
+* DON'T submit PRs that alter licensing related files or headers. If you believe there's a problem with them, file an issue and we'll be happy to discuss it.
+
+Guiding Principals
+------------------
+
+* We allow anyone to participate in our projects. Tasks can be carried out by anyone that demonstrates the capability to complete them
+* Always be respectful of one another. Assume the best in others and act with empathy at all times
+* Collaborate closely with individuals maintaining the project or experienced users. Getting ideas out in the open and seeing a proposal before it's a pull request helps reduce redundancy and ensures we're all connected to the decision making process

LICENSE.txt

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+Copyright (c) 2017 Uber Technologies, Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

README.md

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+## NullAway: Fast Annotation-Based Null Checking for Java [![Build Status](https://travis-ci.org/uber/NullAway.svg?branch=master)](https://travis-ci.org/uber/NullAway)
+
+NullAway is a tool to help eliminate `NullPointerException`s (NPEs) in your Java code.  To use NullAway, first add `@Nullable` annotations in your code wherever a field, method parameter, or return value may be `null`.  Given these annotations, NullAway performs a series of type-based, local checks to ensure that any pointer that gets dereferenced in your code cannot be `null`.  NullAway is similar to the type-based nullability checking in the Kotlin and Swift languages, and the [Checker Framework](https://checkerframework.org/) and [Eradicate](http://fbinfer.com/docs/eradicate.html) null checkers for Java.
+
+NullAway is *fast*.  It is built as a plugin to Error Prone and can run on every single build of your code.  In our measurements, the build-time overhead of running NullAway is usually less than 10%.  NullAway is also *practical*: it does not prevent all possible NPEs in your code, but it catches most of the NPEs we have observed in production while imposing a reasonable annotation burden, giving a great "bang for your buck."  At Uber, we combine NullAway with [RAVE](https://github.com/uber-common/rave) to obtain thorough protection against NPEs in our Android apps.
+
+## Installation
+
+### Overview
+
+NullAway requires that you build your code with [Error Prone](http://errorprone.info), version 2.1.1 or higher.  See the [Error Prone documentation](http://errorprone.info/docs/installation) for instructions on getting started with Error Prone and integration with your build system.  The instructions below assume you are using the Gradle build system; integration with other systems should require similar steps.
+
+### Gradle
+To integrate NullAway into your project add the following to your `build.gradle` file:
+
+```
+buildscript {
+  repositories {
+    maven {
+      url "https://plugins.gradle.org/m2/"
+    }
+  }
+  dependencies {
+    classpath "net.ltgt.gradle:gradle-errorprone-plugin:0.0.11"
+    classpath "net.ltgt.gradle:gradle-apt-plugin:0.11"
+  }
+}
+
+apply plugin: "java"
+apply plugin: "net.ltgt.errorprone"
+apply plugin: "net.ltgt.apt"
+
+configurations.errorprone {
+  resolutionStrategy.force "com.google.errorprone:error_prone_core:2.1.1"
+}
+
+dependencies {
+    apt "com.uber:nullaway:0.1.0"
+
+    compile "com.google.code.findbugs:jsr305:3.0.2"
+}
+
+compileJava {
+    options.compilerArgs += ["-Xep:NullAway:ERROR", "-XepOpt:NullAway:AnnotatedPackages=com.uber"]
+}
+```
+
+Let's walk through this script step by step.  The `buildscript` section of the script pulls in the [Gradle Error Prone plugin](https://github.com/tbroyer/gradle-errorprone-plugin) for Error Prone integration, and the [Gradle APT plugin](https://github.com/tbroyer/gradle-apt-plugin) to ease specification of annotation processor dependencies for a build.  We need the latter since Error Prone loads plugin checkers from the annotation processor path.  Note that the Gradle APT plugin is appropriate for Java projects; for Android projects, use an `annotationProcessor` dependence with the [Android Gradle plugin](https://developer.android.com/studio/releases/gradle-plugin.html).  The `apply plugin` lines load the relevant plugins.  The `configurations.errorprone` section forces our desired Error Prone version.
+
+In `dependencies`, the `apt` line loads NullAway, and the `compile` line loads a [JSR 305](https://jcp.org/en/jsr/detail?id=305) library which provides a suitable `@Nullable` annotation (`javax.annotation.Nullable`).  NullAway allows for any `@Nullable` annotation to be used, so, e.g., `@Nullable` from the Android support or IntelliJ annotations is also fine.
+
+Finally, in the `compileJava` section, we pass some configuration options to NullAway as compiler arguments.  The first argument `-Xep:NullAway:ERROR` is a standard Error Prone argument that sets NullAway issues to the error level; by default NullAway emits warnings.  The second argument, `-XepOpt:NullAway:AnnotatedPackages=com.uber`, tells NullAway that source code in packages under the `com.uber` namespace should be checked for null dereferences and proper usage of `@Nullable` annotations, and that class files in these packages should be assumed to have correct usage of `@Nullable` (see [the docs](https://github.com/uber/NullAway/wiki/Configuration) for more detail).  NullAway requires at least the `AnnotatedPackages` configuration argument to run, in order to distinguish between annotated and unannotated code.  See [the configuration docs](https://github.com/uber/NullAway/wiki/Configuration) for other useful configuration options.
+
+## Code Example
+
+Let's see how NullAway works on a simple code example:
+```java
+static void log(Object x) {
+    System.out.println(x.toString());
+}
+static void foo() {
+    log(null);
+}
+```
+This code is buggy: when `foo()` is called, the subsequent call to `log()` will fail with an NPE.  You can see this error in the NullAway sample app by running:
+```
+cp sample/src/main/java/com/uber/mylib/MyClass.java.buggy sample/src/main/java/com/uber/mylib/MyClass.java
+./gradlew build
+```
+
+By default, NullAway assumes every method parameter, return value, and field is _non-null_, i.e., it can never be assigned a `null` value.  In the above code, the `x` parameter of `log()` is assumed to be non-null.  So, NullAway reports the following error:
+```
+warning: [NullAway] passing @Nullable parameter 'null' where @NonNull is required
+    log(null);
+        ^
+```
+We can fix this error by allowing `null` to be passed to `log()`, with a `@Nullable` annotation:
+```java
+static void log(@Nullable Object x) {
+    System.out.println(x.toString());
+}
+```
+With this annotation, NullAway points out the possible null dereference:
+```
+warning: [NullAway] dereferenced expression x is @Nullable
+    System.out.println(x.toString());
+                        ^
+```
+We can fix this warning by adding a null check:
+```java
+static void log(@Nullable Object x) {
+    if (x != null) {
+        System.out.println(x.toString());
+    }
+}
+```
+With this change, all the NullAway warnings are fixed.
+
+For more details on NullAway's checks, error messages, and limitations, see [our detailed guide](https://github.com/uber/NullAway/wiki).
+
+## Contributors
+
+We'd love for you to contribute to our open source projects. Before we can accept your contributions, we kindly ask you to sign our [Uber Contributor License Agreement](https://docs.google.com/a/uber.com/forms/d/1pAwS_-dA1KhPlfxzYLBqK6rsSWwRwH95OCCZrcsY5rk/viewform).
+
+- If you **find a bug**, open an issue or submit a fix via a pull request.
+- If you **have a feature request**, open an issue or submit an implementation via a pull request
+- If you **want to contribute**, submit a pull request.
+
+## License
+
+NullAway is licensed under the MIT license.  See the LICENSE.txt file for more information.

RELEASING.md

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+Releasing
+=========
+
+ 1. Change the version in `gradle.properties` to a non-SNAPSHOT version.
+ 2. Update the `CHANGELOG.md` for the impending release.
+ 3. Update the `README.md` with the new version.
+ 4. `git commit -am "Prepare for release X.Y.Z."` (where X.Y.Z is the new version)
+ 5. `git tag -a X.Y.Z -m "Version X.Y.Z"` (where X.Y.Z is the new version)
+ 6. `./gradlew clean uploadArchives`
+ 7. Update the `gradle.properties` to the next SNAPSHOT version.
+ 8. `git commit -am "Prepare next development version."`
+ 9. `git push && git push --tags`
+ 10. Visit [Sonatype Nexus](https://oss.sonatype.org/) and promote the artifact.

build.gradle

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+/*
+ * Copyright (C) 2017. Uber Technologies
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+subprojects {
+    buildscript {
+        repositories {
+            jcenter()
+            maven {
+               url "https://plugins.gradle.org/m2/"
+            }
+        }
+    }
+
+    repositories {
+        jcenter()
+    }
+
+}
+
+apply from: 'gradle/dependencies.gradle'

config/checkstyle/checkstyle-suppressions.xml

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+<?xml version="1.0"?>
+
+<!DOCTYPE suppressions PUBLIC
+    "-//Puppy Crawl//DTD Suppressions 1.1//EN"
+    "http://www.puppycrawl.com/dtds/suppressions_1_1.dtd">
+
+<suppressions>
+    <suppress checks="JavadocType" files="[\\/]test[\\/]" />
+    <suppress checks="JavadocMethod" files="[\\/]test[\\/]" />
+</suppressions>