Many tools can be used in Java to build applications. Open source products are Ant, Ivy, Maven, and the more recent Gradle. For convenience, as Maven the most popular in this book we will use it to build our examples.

Apache Maven is a software project management and comprehension tool. Based on the concept of project object model (POM), Maven can manage a project's build, reporting, and documentation from a central piece of information.

We will use Maven to manage our projects. With Maven we will get a simple starting point to build, execute, and test our projects. Maven 3.3.9 is downloadable from https://maven.apache.org/download.cgi.

Since we have installed JDK 8 in our machine, we can extract the downloaded Maven ZIP and put it in any folder that we prefer. After that, we will need a system variable, MAVEN_HOME, for our system. In Linux, you can set MAVEN_HOME by editing the .bash_profile file in your home directory:

vi $USER_HOME/.bash_profile
export MAVEN_HOME=/$your_home_path/apache-maven-3.3.9
export path:$MAVEN_HOME/bin

The second row lets you use Maven in any folder path. So, for example, in /etc, you can run the Maven command mvn. A Maven guide is not given in this book, but for those who don’t know Maven, we will use only three commands:

• mvn clean: Used to clean the project
• mvn install: Used to build, install, and test the project and create the packages to deploy in WildFly
• mvn test: Used only to execute test cases

All the commands can be used together. For example:

The mvn clean install command will execute both the commands, first cleaning the project and then installing it. If you avoid tests it's enough add the property:

mvn clean install -DskipTests

Maven can be used only in the folder for Maven projects. A Maven project is recognized by a file contained in the root of the folder, pom.xml. It is the key descriptor of the Maven projects. For example in this POM file you put the dependency libraries of the projects. When you install a project, it automatically downloads the mandatory dependencies if they are not present and it compiles with them.