# Gradle training

Training files for learning Gradle

Further resources:
 - YSofters blog - http://www.ysofters.com/tag/gradle/
 - Georgik's blog - http://georgik.sinusgear.com/tag/gradle/

##01-build-and-test

Example contains one class and one simple test written in TestNG.
List all available tasks:

    gradle tasks

Try to compile source code:

    gradle jar

Run tests:

    gradle tests

Test report is available in build/reports/tests/index.html


## 02-pmd

Execute PMD check on project.

    gradle check

You should see one warning about empty if statement in source code.
Results are stored in: build/reports/pmd/main.html


## 03-checkstyle

Execute Checkstyle on project. Configuration of Checkstyle is stored in config/checkstyle/checkstyle.xml

    gradle check

Error report is available in file: build/reports/checkstyle/main.xml


## 04-findbugs

Execute FindBugs on project.

    gradle check

Report is available in file: build/reports/findbugs/main.html


## 05-jdepend

Execute JDepend on project.

    gradle check

Report is available in file: build/reports/jdepend/main.txt
You should see there one dependency cyle.


## 06-maven-deployer

Upload artifact to local repo (directory).

    gradle uA

Artifact will be stored at: /idea/training/repo


## 07-c-language

It is possible to build project written in C language by gradle.
Gradle automatically detects toolchain e.g. Visual Studio or GCC.

    gradle mainExecutable

Binary is stored in build/exe/main


## 08-c-visual-studio

Gradle is able to generate project files for Visual Studio for C/C++.

    gradle mainVisualStudio
    ii .\visualStudio\mainExe.sln

Solution file is stored in visualStudio/mainExe.sln


## 09-custom-task-dolast

Gradle evaluates build scripts in two phases. The first one is configuration.
Gradle examines each task definition and execute code in definition.
The second phase is execution where it actually executes code.
The code is stored in doLast block. If you omit that block then println
will execute always even when you run `gradle tasks`

    gradle tasks
    gradle helloWorld


## 10-custom-task-dofirst

doLast allows to append execution code at the end of task. There is another
method doFirst which prepends code before current code. It's useful when
building decorators.

    gradle tasks
    gradle helloWorld


## 11-task-class

Gradle allows to define custom task class. This class should contain
one method with annotation @TaskAction. This method will be executed.
Each property defined on class level is configurable from gradle task
(see verboseToday).

    gradle tasks
    gradle today
    gradle verboseToday


## 12-custom-plugin

It's possible to specify tasks outside build.gradle and then "include" file. 
Gradle uses notion of plugins. Check helloPlugin.gradle file.

    gradle tasks
    gradle helloFromPlugin


## 13-plugin-from-gist

Gradle allows to include code/plugins from network resource.
In this example plugin is stored as gist at Github
- https://gist.github.com/georgik/71663c6d8d4e01783733

    gradle tasks
    gradle helloFromGist


## 14-custom-groovy-plugin

Example of stand alone plugin written in Groovy. Compile and install this
plugin to your local Maven repository. Then you will be able to use it in
the next example.

    gradle install

Pay attention to special file: src/main/resources/META-INF/gradle-pluginslines-count.properties
This file will cause that it will be possible to apply plugin by it's id instead
of java class name. It's preferred solution in Gradle world, because it gives
you more flexibility when changing plugin implementation


## 15-use-custom-plugin

You need to install plugin to your local Maven storage (see example 14.).
This example shows how to include plugin from local Maven storage.
Plugin is just counting lines in build.gradle file in current directory.

    gradle tasks
    gradle countLines

## 16-stop-build

It is possible to stop build by throwing exception.

    gradle workingTask
    gradle failingTask


## 17-testng-groovy

Example combines usage of TestNG for testing and tests written in Groovy.
It is necessary to declare 'useTestNG()' in test configuration.
Otherwise tests won't be executed.

    gradle test

Reports are stored in build/reports/tests/index.html

## 18-debug-gradle-script

Do not run in daemon mode.
Set environment variable GRADLE_OPTS to

    "-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005"

Start gradle task

    gradle hello

Attach remote debugger from Ide.

More information: http://georgik.sinusgear.com/2014/06/23/how-to-debug-gradle-script/

## 19-war-jetty

Simple web app deployed to local jetty. It will compile sources from
src/main/webapp into web application.

    gradle jettyRun

Application is accessible at: http://localhost:8080/19-war-jetty

Press CTRL+C to stop server.

## 20-grails

Grails is framework for building web applications. 
This example let you bootstrap initial Grails project.

    gradle init

Gradle Grails plugin will create project skeleton.
You can start sample portal by:

    gradle grails-run-app

Result is available at: http://localhost:8080/20-grails

More information: https://github.com/grails/grails-gradle-plugin
Video recording from Building Grails App With Gradle: http://youtu.be/FwZvDU2Jeh8


## 21-custom-task-in-one-file

Gradle has support for defining custom task classes.
Task class could be extended e.g. from DefaultTask.

You can verify this sample by:

    gradle hello
    gradle greeting

## 22-custom-task-in-buildSrc

In previous example we discussed how to add custom task. Storing many
custom tasks in one file makes it unreadable. It's possible to split logic into
Groovy classes.

Create buildSrc directory with src/main/groovy.
Store here the class. It's necessary to add package name declaration and imports
from GradleAPI.

Functionality is the same:

    gradle hello
    gradle greeting