Gradle is a build automation tool. It can automate build-related tasks such as

  • Running tests

  • Managing library dependencies

  • Analyzing code for style compliance

The gradle configuration for this project is defined in the build script build.gradle.

To learn more about gradle build scripts, refer Build Scripts Basics.

Running Gradle Commands

To run a Gradle command, open a command window on the project folder and enter the Gradle command. Gradle commands look like this:

  • On Windows: gradlew <task1> <task2> …​ e.g. gradlew clean test

  • On Mac/Linux: ./gradlew <task1> <task2>…​ e.g. ./gradlew clean test

If you do not specify any tasks, Gradlew will run the default tasks clean test coverage

Cleaning the Project

  • clean
    Deletes the files created during the previous build tasks (e.g. files in the build folder). e.g. ./gradlew clean

clean to force Gradle to execute a task:
When running a Gradle task, Gradle will try to figure out if the task needs running at all. If Gradle determines that the output of the task will be same as the previous time, it will not run the task. For example, it will not build the JAR file again if the relevant source files have not changed since the last time the JAR file was built. If we want to force Gradle to run a task, we can combine that task with clean. Once the build files have been clean ed, Gradle has no way to determine if the output will be same as before, so it will be forced to execute the task.

Creating the JAR file

  • shadowJar
    Creates the addressbook.jar file in the build/jar folder, if the current file is outdated.
    e.g. ./gradlew shadowJar

To force Gradle to create the JAR file even if the current one is up-to-date, you can ‘clean’ first.
e.g. ./gradlew clean shadowJar

Why do we create a fat JAR? If we package only our own class files into the JAR file, it will not work properly unless the user has all the other JAR files (i.e. third party libraries) our classes depend on, which is rather inconvenient. Therefore, we package all dependencies into a single JAR files, creating what is also known as a fat JAR file. To create a fat JAR file, we use the Gradle plugin shadow jar.

Rendering AsciiDoc files

  • asciidoctor
    Converts AsciiDoc files in docs to HTML format. Generated HTML files can be found in build/docs.

  • deployOfflineDocs
    Updates the offline user guide, and its associated files, used by the Help window in the application. Deployed HTML files and images can be found in src/main/resources/docs.

Running the application

  • run
    Builds and runs the application.

  • runShadow
    Builds the application as a fat JAR, and then runs it.

Running code style checks

  • checkstyleMain
    Runs the code style check for the main code base

  • checkstyleTest
    Runs the code style check for the test code base

The set of code style rules implemented can be found in config/checkstyle/checkstyle.xml. To enable exceptions to code styles, add in the comment //CODESTYLE.OFF: RuleName at the start of the section and //CODESTYLE.ON: RuleName at the end of the section.

Running Tests

  • test
    Runs all tests.

Here are some examples:

  • ./gradlew test — Runs all tests

  • ./gradlew clean test — Cleans the project and runs tests

Updating Dependencies

There is no need to run these Gradle tasks manually as they are called automatically by other relevant Gradle tasks.

  • compileJava
    Checks whether the project has the required dependencies to compile and run the main program, and download any missing dependencies before compiling the classes.
    See build.gradle → allprojects → dependencies → compile for the list of dependencies required.

  • compileTestJava
    Checks whether the project has the required dependencies to perform testing, and download any missing dependencies before compiling the test classes.
    See build.gradle → allprojects → dependencies → testCompile for the list of dependencies required.