findbugs-exclude.xml

<FindBugsFilter>
    <Match>
        <Class name="~.*R\$.*"/>
    </Match>
    <Match>
        <Class name="~.*Manifest\$.*"/>
    </Match>
    <Match>
        <Class name="~.*_234$"/>
    </Match>
    <Match>
        <Bug pattern="EI_EXPOSE_REP"/>
    </Match>
    <Match>
        <Bug pattern="EI_EXPOSE_REP2"/>
    </Match>
</FindBugsFilter>

pmd-ruleset.xml

<?xml version="1.0"?>
<ruleset xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" name="Android Application Rules"
         xmlns="http://pmd.sf.net/ruleset/1.0.0"
         xsi:noNamespaceSchemaLocation="http://pmd.sf.net/ruleset_xml_schema.xsd"
         xsi:schemaLocation="http://pmd.sf.net/ruleset/1.0.0 http://pmd.sf.net/ruleset_xml_schema.xsd">

    <description>Custom ruleset for Android application</description>

    <exclude-pattern>.*/R.java</exclude-pattern>
    <exclude-pattern>.*/gen/.*</exclude-pattern>

    <rule ref="rulesets/java/android.xml"/>
    <rule ref="rulesets/java/clone.xml" />
    <rule ref="rulesets/java/finalizers.xml" />
    <rule ref="rulesets/java/imports.xml" />
    <rule ref="rulesets/java/logging-java.xml" />
    <rule ref="rulesets/java/braces.xml" />
    <rule ref="rulesets/java/strings.xml" />
    <rule ref="rulesets/java/basic.xml" />
    <rule ref="rulesets/java/naming.xml">
        <exclude name="AbstractNaming" />
        <exclude name="LongVariable" />
        <exclude name="ShortMethodName" />
        <exclude name="ShortVariable" />
        <exclude name="AvoidFieldNameMatchingMethodName" />
        <exclude name="VariableNamingConventions" />
    </rule>
    <rule ref="rulesets/java/imports.xml/TooManyStaticImports">
        <properties>
            <property name="maximumStaticImports" value="15" />
        </properties>
    </rule>
</ruleset>

qa-check.gradle

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

task checkstyle(type: Checkstyle) {
    description 'Checks if the code is somewhat acceptable'
    group 'verification'

    configFile file('./qa-checks/checkstyle.xml')
    source 'src'
    include '**/*.java'
    exclude '**/gen/**'

    classpath = files()
    ignoreFailures = false
}

task findbugs(type: FindBugs) {
    description 'Run findbugs'
    group 'verification'

    classes = files("$project.buildDir/intermediates/classes")
    source 'src'
    classpath = files()

    effort 'max'
    excludeFilter file('./qa-checks/findbugs-exclude.xml')

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

    ignoreFailures = true
}

task pmd(type: Pmd) {
    description 'Run PMD'
    group 'verification'

    ruleSetFiles = files("./qa-checks/pmd-ruleset.xml")
    ruleSets = []

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

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

    ignoreFailures = true
}

assembleDebug.doLast {
    project.tasks.getByName("checkstyle").execute()
    project.tasks.getByName("findbugs").execute()
    project.tasks.getByName("pmd").execute()
    project.tasks.getByName("lint").execute()
}