Gradle is the build system you have been waiting for or maybe the build system that has been waiting for you. The adoption rate is incredible from being the new Google Android development tools build system to most new Java opensource projects to JavaScript based front-end and back-end projects.

1. Gradle: The Build System
Corneil du Plessis
corneil.duplessis@gmail.com
@corneil

2. Gradle: Introduction
The Build System you have been waiting for.

3. Gradle: Introduction
 Scope
 History Lesson
- Make
- Ant
- Maven
 Gradle

4. Gradle: Make
 Targets, dependencies, rules
 Sample:
CFLAGS ?= -g
all: helloworld
helloworld: helloworld.o
# Commands start with TAB not spaces
$(CC) $(LDFLAGS) -o $@ $^
helloworld.o: helloworld.c
$(CC) $(CFLAGS) -c -o $@ $<
 Suffix rules:
.c.o:
$(CC) $(CFLAGS) -c $<

5. Gradle: Ant
 Projects, targets, dependency, built-in tasks, taskdef.
 <project name="My Project" default="all" basedir=".">
<property name="app.name" value="hello"/>
<property name="tcserver.home" value="/opt/tomcat-6.0.25.A.RELEASE"
/>
<property name="work.home" value="${basedir}/work"/>
<property name="dist.home" value="${basedir}/dist"/>
<property name="src.home" value="${basedir}/src"/>
<property name="web.home" value="${basedir}/web"/>
<path id="compile.classpath">
<fileset dir="${tcserver.home}/bin">
<include name="*.jar"/>
</fileset>
<pathelement location="${tcserver.home}/lib"/>
<fileset dir="${tcserver.home}/lib">
<include name="*.jar"/>
</fileset>
</path>

6. Gradle: Ant – cont.
 <target name="all" depends="clean,compile,dist" description="Clean work dirs, then compile and create a WAR"/>
<target name="clean" description="Delete old work and dist directories">
<delete dir="${work.home}"/>
<delete dir="${dist.home}"/>
</target>
<target name="prepare" depends="clean" description="Create work dirs copy static files to work dir">
<mkdir dir="${dist.home}"/>
<mkdir dir="${work.home}/WEB-INF/classes"/>
<copy todir="${work.home}">
<fileset dir="${web.home}"/>
</copy>
</target>
<target name="compile" depends="prepare" description="Compile sources and copy to WEB-INF/classes dir">
<javac srcdir="${src.home}" destdir="${work.home}/WEB-INF/classes">
<classpath refid="compile.classpath"/>
</javac>
<copy todir="${work.home}/WEB-INF/classes">
<fileset dir="${src.home}" excludes="**/*.java"/>
</copy>
</target>
<target name="dist" depends="compile"
description="Create WAR file for binary distribution">
<jar jarfile="${dist.home}/${app.name}.war"
basedir="${work.home}"/>
</target>
</project>

7. Gradle: Maven
 POM, Goals, Lifecycle, Plugins, Profiles
 Maven Repository
 <project
xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.mkyong</groupId>
<artifactId>CounterWebApp</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>CounterWebApp Maven Webapp</name>
<url>http://maven.apache.org</url>
<properties>
<spring.version>3.2.8.RELEASE</spring.version>
<junit.version>4.11</junit.version>
<jdk.version>1.6</jdk.version>
</properties>

8. Gradle: Maven – cont
 <dependencies>
<!-- Spring 3 dependencies →
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
</dependency>
</dependencies>

9. Gradle: Maven – cont
 <build>
<finalName>CounterWebApp</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.0</version>
<configuration>
<source>${jdk.version}</source>
<target>${jdk.version}</target>
</configuration>
</plugin>
</plugins>
</build>
</project>

10. Gradle: What is it?
 Gradle is a Groovy DSL for creating build scripts
 Gradle has a beautiful designed model for Tasks,
Dependencies, Conventions etc.
 Gradle understands Ivy and Maven repositories
 Gradle can execute Ant scripts and tasks directly

11. Gradle: What does it look like?
 gradle.properties
springVersion=3.2.8.RELEASE
junitVersion=4.11
 settings.gradle
rootProject.name = 'CounterWebApp'
 build.gradle
apply plugin: 'java'
apply plugin: 'war'
repositories {
mavenCentral()
}
group = 'com.mkyong'
archivesBaseName = 'CounterWebApp'
version = '1.0-SNAPSHOT'
sourceCompatibility = 1.6
dependencies {
compile 'org.springframework:spring-core:${springVersion}'
compile 'org.springframework:spring-web:${springVersion}'
compile 'org.springframework:spring-webmvc:${springVersion}'
testCompile group: 'junit', name: 'junit', version: junitVersion
}

12. Gradle: Artifacts
 build.gradle
- buildScript
- configurations
- dependencies
- apply plugin
- artifacts
- sourceSets
- other dsl sections and Groovy
 settings.gradle
- subprojects
 gradle.properties

13. Gradle: Builtin Support
 Ant Projects, Tasks
 Java, Jar, War, Ear
 Scala, Groovy
 Sonar, Pmd, Jacoco, CheckStyle, FindBugs, CodeNarc,
JDepend
 Maven Publish, Ivy Publish
 Jetty
 GNU Compilers, Clang, Visual C++
 Eclipse, IdeaJ, Netbeans

14. Gradle: Create scripts
 Create build.gradle and other files
- Basic, Java Library, Scala Library, Groovy Library
- Convert pom
 gradle init –type <project-type>
 Checkout lazybones at
https://github.com/pledbrook/lazybones

15. Gradle: Demo
 Conversion from pom
 Custom Tasks

16. Gradle: 3rd Party plugins
 http://plugins.gradle.org
 Google Android Development
 Bintray publishing.
 Artifactory
 Spring IO Framework
 https://github.com/nebula-plugins
 Google App Engine
 Tomcat
 lessCss, minCss, minJs

17. Gradle – Questions
 Discuss on JUG Facebook
 http://www.slideshare.net/CorneilduPlessis
 https://www.facebook.com/groups/jozijug