We have seen how we can write tasks in a Gradle build and how we can execute them, but we haven't seen how we can do real-life tasks such as compiling source code or testing with Gradle.
In this chapter, we will learn how we can use the Gradle Java plugin to get tasks for compiling and packaging a Java project. We will also see how Gradle's build-by-convention features make it very easy to start and work with source code.
In Gradle, we can apply plugins to our project. A plugin basically adds extra functionalities such as tasks and properties to our project. By using a plugin, functionality is decoupled from the core Gradle build logic. We can write our own plugins, but Gradle also ships with plugins that are ready out of the box. For example, Gradle has a Java plugin. This plugin adds tasks for compiling, testing, and packaging Java source code to our project.
The plugins that are packaged with a Gradle version are never updated or changed for that version, so if new functionality is added to a plugin, a whole new Gradle version will be released. In future versions of Gradle, this will change. This doesn't apply for the plugins we write ourselves. We can release new versions of our own plugins, independent of the Gradle version.