Get Android gradle plugin & checkstyle working together / command line usage

Question

I'm evaluating the ability of the new gradle-based build system to reproduce our current ant-based build process and, as a gradle beginner, I failed to get checkstyle running with the android gradle plugin.

Environment:

• gradle 1.6 running fine on a standard java project (checkstyle check target included)

• up-to-date android SDK (22.0.1 with platform tools and build tools 17)

• no eclipse, no android studio, only my lovely terminal

Symptom:

The target project is https://github.com/nibua-r/LigoTextDemo and I succeeded to build it using gradle but if I naively add apply plugin: checkstyle to my build.gradle:

buildscript {
  repositories {
    mavenCentral()
  }
  dependencies {
    classpath 'com.android.tools.build:gradle:0.4.2'
  }
}
apply plugin: 'android'
apply plugin: 'checkstyle'

android {
  buildToolsVersion '17'
  compileSdkVersion 15
  testBuildType 'debug'

  defaultConfig {
    versionCode = 1
    versionName = '1.0'
    minSdkVersion 12
    targetSdkVersion 15
  }

  buildTypes {
    debug {
      packageNameSuffix = '.debug'
    }
  }
}

then gradle check doesn't even complain on not finding the checkstyle.xml file (at the default config/checkstyle location) and returns:

:check UP-TO-DATE

BUILD SUCCESSFUL

What's needed:

First, I just need a running checkstyle target. Then, I need to automate checkstyle running as a dependency of the compilation (but lets get the chekstyle target up and running first).

Assumption:

This may be related to the fact that (from the [user guide][1]):

The Android plugin […] uses its own sourceSets

but I'm not enough gradle-efficient to understand what I'm missing there. Please, gradle Master, enlighten me with your valuable knowledge!

Answer 1

I got pmd, findbugs, and checkstyle working with Gradle 1.12 android plugin 0.12.+ using the following script:

apply plugin: 'checkstyle'
apply plugin: 'findbugs'
apply plugin: 'pmd'

check.dependsOn 'checkstyle', 'findbugs', 'pmd'

task checkstyle(type: Checkstyle) {
    configFile file("${project.rootDir}/config/quality/checkstyle/checkstyle.xml")
    source 'src'
    include '**/*.java'
    exclude '**/gen/**'

    classpath = files()
}

task findbugs(type: FindBugs) {
    ignoreFailures = true
    effort = "max"
    reportLevel = "high"
    excludeFilter = new File("${project.rootDir}/config/quality/findbugs/findbugs-filter.xml")
    classes = files("$project.buildDir/intermediates/classes/")

    source 'src'
    include '**/*.java'
    exclude '**/gen/**'

    reports {
        xml {
            destination "$project.buildDir/reports/findbugs/findbugs.xml"
            xml.withMessages true
        }
    }

    classpath = files()
}

task pmd(type: Pmd) {
    ruleSetFiles = files("${project.rootDir}/config/quality/pmd/pmd-ruleset.xml")
    ignoreFailures = true
    ruleSets = ["basic", "braces", "strings"]

    source 'src'
    include '**/*.java'
    exclude '**/gen/**'

    reports {
        xml.enabled = true
        html.enabled = false
    }
}

Running gradle build in command line will run all code quality plugins and generate xml reports in app/build/reports/ which are then ready to be viewed or parsed by CI tools.

Answer 2

Someone has a great answer to solve integrating PMD, findbugs and checkstyle with Gradle for Android. Unfortunately, the only solution for now is based on ant : http://sethrylan.org/2013/07/14/gradle-android-findbugs.html

I wish gradle will one day allow to do as much as maven for Android.

--- Update as of October 2013

With Gradle 1.8 and Android plugin for Gradle 0.6.+, you don't need this anymore. Android sourcesets and configurations are now compatible with the java plugin and all quality plugin work out of the box.

This includes pmd, findbugs, checkstyle and classycle.

--- Update A configuration, largely inspired from the project mentioned above, is proposed in this open source project as well, plus other tools.

Answer 3

To get this to work with my Android project, I had to declare the task explicitly.

Here's what worked for me:

apply plugin: 'checkstyle'

task checkstyle(type: Checkstyle) {
    source 'src'
    include '**/*.java'
    exclude '**/gen/**'

    // empty classpath
    classpath = files()
}

Be mindful that the Android plugin may choose to create a task of the same name in the future or work in conjunction with the checkstyle plugin in different ways.

Answer 4

You can try Android Check plugin (https://github.com/noveogroup/android-check):

• Checkstyle
• PMD

Configuration:

buildscript {
    repositories { jcenter() }
    dependencies {
        ...
        classpath 'com.noveogroup.android:check:+'
        ...
    }
}

apply plugin: 'com.noveogroup.android.check'

You can use hardcore configuration:

check {
    abortOnError true
    checkstyle { config hard() }
    pmd { config hard() }
}

Answer 5

I found by digging on the web that the Android plugin depends on java-base and not java (i.e. the sourceSets management is specific) and the checkstyle plugin rely on java. As a consequence, some gradle upstream modification are needed to get the thing done. The gradle team is working on that, as seen on twitter:

@anzix Android source sets will be soon understood by the generic code quality plugins. Work on that has already started.

— Gradle Build System (@Gradleware) May 26, 2013

Answer 6

Take a look at the Soter Gradle plugin to semlessly add support for Findbugs, Checkstyle and PMD to Android projects.