maven.tar.gz

Maven is the de-facto build tool of choice for Java projects and has wide adoption at the enterprise level.

In this course, you will learn the fundamentals of Maven so that you can start to inject build automation into your own projects. You’ll start by exploring the basics such as plugins, goals, coordinates, and lifecycles.

In the latter half, you will dive into more advanced concepts such as dependencies, inheritance, aggregation, and build profiles. 

By the end of this course, you will have just the right amount of knowledge for you to quickly become productive when working with Maven.

Build Java Projects with Maven

## Plugin
Maven can accept _plugins_ to perform various tasks. The core of Maven is limited and small, a harness that leverages the intelligence of the plugins attached to it to perform various tasks. Some of the most common plugins are:

1. **Compiler Plugin**: contains the logic to compile
2. **Jar Plugin**: contains the logic to create jars
3. **Surefire Plugin**: contains the logic to execute unit tests

There are numerous other plugins that can be used. In fact, we can even write our own plugins. Remember, plugins are nothing but code that implement the logic to perform various tasks during the build process.

## Goal

A Maven plugin consists of _goals_ which is a **unit of work**. You can think of it as representing _the capability of a plugin_. A goal is an action we want to take on the project defined by a _POM_ (covered later) file. The following illustration shows the relationship between the different entities we've discussed so far.

We can examine the goals in a particular plugin using Maven's _help_ plugin. You can execute the commands in the widget below and see the goals printed out for the compiler plugin. The command is:

```shell
mvn help:describe -Dplugin=org.apache.maven.plugins:maven-compiler-plugin
```

The output of the above command is:

The command invokes the **describe** goal of the **help** plugin specified as **help:describe**. The goal takes arguments from the command line, which we specify using **-D**. The argument **-Dplugin**  specifies the plugin we want to get details for.

# Execute the following command to see the details for the compiler plugin
mvn help:describe -Dplugin=org.apache.maven.plugins:maven-compiler-plugin

# We add the argument -Ddetail and now the output gives detailed description
# of each plugin goal.
mvn help:describe -Dplugin=org.apache.maven.plugins:maven-compiler-plugin -Ddetail

Interestingly, we can also list the goals of the _help_ plugin using the help plugin itself as follows:

```shell
mvn help:describe -Dplugin=org.apache.maven.plugins:maven-help-plugin
```

The result will be:

In summary, Maven uses plugins to execute build tasks and each plugin consists of one or more goals. 

# Plugin
Maven can accept _plugins_ to perform various tasks. The core of Maven is limited and small, a harness that leverages the intelligence of the plugins attached to it to perform various tasks. Some of the most common plugins are:

1. **Compiler Plugin**: contains the logic to compile
2. **Jar Plugin**: contains the logic to create jars
3. **Surefire Plugin**: contains the logic to execute unit tests

There are numerous other plugins that can be used. In fact, we can even write our own plugins. Remember, plugins are nothing but code that implement the logic to perform various tasks during the build process.

# Goal

A Maven plugin consists of _goals_ which is a **unit of work**. You can think of it as representing _the capability of a plugin_. A goal is an action we want to take on the project defined by a _POM_ (covered later) file. The following illustration shows the relationship between the different entities we've discussed so far.

This lesson explains Maven's core concepts, plugins and goals.

Theory

Plugins and Goals

Plugin

Goal