Sample Build.Gradle that adds the two lines to enable New Relic Logs in Context for Log4J v2.x.

build.gradle

//
// This is a full example showing the two lines you need to add to your Gradle file to enable New Relic Logs in Context.
// Most of this file is stock - the only changes needed shown below, flagged with comments.
//
description = 'Ad Service'

buildscript {
    repositories {
        mavenCentral()
        mavenLocal()
        maven {
            url "https://plugins.gradle.org/m2/"
        }
    }
    dependencies {
        classpath 'com.google.protobuf:protobuf-gradle-plugin:0.8.3'
        classpath "gradle.plugin.com.github.sherter.google-java-format:google-java-format-gradle-plugin:0.7.1"
    }
}

apply plugin: 'idea'
apply plugin: 'java'
apply plugin: 'com.google.protobuf'
apply plugin: 'com.github.sherter.google-java-format'

repositories {
    mavenCentral()
    mavenLocal()
}

configurations {
    newrelic
}

group = "adservice"
version = "0.1.0-SNAPSHOT"

def opencensusVersion = "0.18.0"
def grpcVersion = "1.17.0"
def jacksonVersion = "2.9.6"

tasks.withType(JavaCompile) {
    sourceCompatibility = '1.8'
    targetCompatibility = '1.8'
}

ext {
    speed = project.hasProperty('speed') ? project.getProperty('speed') : false
    offlineCompile = new File("$buildDir/output/lib")
    newrelicVersion = '5.8.0'
}

dependencies {
    newrelic "com.newrelic.agent.java:newrelic-agent:${newrelicVersion}"
    
    //New Relic Logs in Context - Add this line for Log4J support.
    compile("com.newrelic.logging:log4j2:1.0-rc2")

    if (speed) {
        compile fileTree(dir: offlineCompile, include: '*.jar')
    } else {
        compile "com.google.api.grpc:proto-google-common-protos:1.12.0",
                "io.opencensus:opencensus-api:${opencensusVersion}",
                "io.opencensus:opencensus-contrib-grpc-util:${opencensusVersion}",
                "io.opencensus:opencensus-exporter-trace-jaeger:${opencensusVersion}",
                "io.opencensus:opencensus-exporter-stats-stackdriver:${opencensusVersion}",
                "io.opencensus:opencensus-exporter-trace-stackdriver:${opencensusVersion}",
                "io.opencensus:opencensus-exporter-trace-logging:${opencensusVersion}",
                "io.grpc:grpc-protobuf:${grpcVersion}",
                "io.grpc:grpc-stub:${grpcVersion}",
                "io.grpc:grpc-netty:${grpcVersion}",
                "io.grpc:grpc-services:${grpcVersion}",
                "org.apache.logging.log4j:log4j-core:2.11.1"

        runtime "com.fasterxml.jackson.core:jackson-core:${jacksonVersion}",
                "com.fasterxml.jackson.core:jackson-databind:${jacksonVersion}",
                "io.opencensus:opencensus-contrib-log-correlation-log4j2:${opencensusVersion}",
                "io.opencensus:opencensus-impl:${opencensusVersion}",
                "io.netty:netty-tcnative-boringssl-static:2.0.8.Final"
    }
}

protobuf {
    protoc {
        artifact = 'com.google.protobuf:protoc:3.5.1-1'
    }
    plugins {
        grpc {
            artifact = "io.grpc:protoc-gen-grpc-java:${grpcVersion}"
        }
    }
    generateProtoTasks {
        all()*.plugins {
            grpc {}
        }
        ofSourceSet('main')
    }
}

googleJavaFormat {
    toolVersion '1.7'
}

// Inform IDEs like IntelliJ IDEA, Eclipse or NetBeans about the generated code.
sourceSets {
    main {
        java {
            srcDirs 'hipstershop'
            srcDirs 'build/generated/source/proto/main/java/hipstershop'
            srcDirs 'build/generated/source/proto/main/grpc/hipstershop'
        }
    }
}

// Provide convenience executables for trying out the examples.
apply plugin: 'application'

startScripts.enabled = false

// This to cache dependencies during Docker image building. First build will take time.
// Subsequent build will be incremental.
task downloadRepos(type: Copy) {
    from configurations.compile
    into offlineCompile
    from configurations.runtime
    into offlineCompile
}

task adService(type: CreateStartScripts) {
    mainClassName = 'hipstershop.AdService'
    applicationName = 'AdService'
    outputDir = new File(project.buildDir, 'tmp')
    classpath = jar.outputs.files + project.configurations.runtime
    
    // New Relic Logs in Context - set log4j2.messageFactory.
    defaultJvmOpts =
        ["-javaagent:/app/build/libs/newrelic.jar","-Dnewrelic.config.file=/app/newrelic/newrelic.yml","-Dnewrelic.config.app_name=adservice-server","-Dlog4j2.messageFactory=com.newrelic.logging.log4j2.NewRelicMessageFactory"]
}

task adServiceClient(type: CreateStartScripts) {
    mainClassName = 'hipstershop.AdServiceClient'
    applicationName = 'AdServiceClient'
    outputDir = new File(project.buildDir, 'tmp')
    classpath = jar.outputs.files + project.configurations.runtime
    
     // New Relic Logs in Context - set log4j2.messageFactory.
    defaultJvmOpts =
        ["-javaagent:/app/build/libs/newrelic.jar","-Dnewrelic.config.file=/app/newrelic/newrelic.yml","-Dnewrelic.config.app_name=adservice-client","-Dlog4j2.messageFactory=com.newrelic.logging.log4j2.NewRelicMessageFactory"]
}

task copyAgent(type: Copy) {
    from { configurations.newrelic } into "$buildDir/libs"
    from { "newrelic/newrelic.yml "} into "$buildDir/libs"

    rename ("newrelic-agent-${newrelicVersion}.jar", 'newrelic.jar')
}

applicationDistribution.into('bin') {
    from(adService)
    from(adServiceClient)
    fileMode = 0755
}

adService.dependsOn copyAgent
adServiceClient.dependsOn copyAgent