Installing Apache Maven

Installing Maven on any platform is more than a straightforward task. At the time of writing this book, the latest version was 3.3.3, which is available for download at http://maven.apache.org/download.cgi. This version requires JDK 1.7.0 or above.

Tip

You should keep a note on the Java requirement for version 3.3.3, if you are planning to upgrade from versions 3.0.*, 3.1.*, or 3.2.*. Prior to Maven 3.3.x, the only requirement was JDK 1.5.0. or JDK 1.6.0 (for 3.2.*).

Apache Maven is an extremely lightweight distribution. It does not have any hard requirements on memory, disk space, or CPU. Maven itself is built on top of Java, and it would work on any operating system that runs Java virtual machine (JVM).

Installing Apache Maven on Ubuntu

Installing Maven on Ubuntu is a single line command. Proceed with the following steps:

1. Run the following apt-get command in the command prompt. You need to have the sudo privileges to execute this:

   $ sudo apt-get install maven
   

2. This takes a few minutes to complete. Upon the completion of the installation, you can run the following command to verify the installation:

   $ mvn -version
   

3. You should get an output similar to the following, if Apache Maven has been installed successfully:

   $ mvn -version
   Apache Maven 3.3.3
   Maven home: /usr/share/maven
   Java version: 1.7.0_60, vendor: Oracle Corporation
   Java home: /usr/lib/jvm/java-7-oracle/jre
   Default locale: en_US, platform encoding: UTF-8
   OS name: "linux", version: "3.13.0-24-generic", arch: "amd64", family: "unix"
   

4. Maven is installed under the /usr/share/maven directory. To check the directory structure behind the Maven installation directory, use the following command:

   $ ls /usr/share/maven
   bin  boot  conf  lib  man
   

5. Maven configuration files can be found at /etc/maven, which can be listed using the following command:

   $ ls /etc/maven
   m2.conf  settings.xml
   

If you don't want to work with the apt-get command, there is another way of installing Maven under any Unix-based operating system. We will discuss this in the next section. Since Mac OS X has a kernel built at the top of the Unix kernel, installing Maven on Mac OS X would be the same as installing it on any Unix-based operating system.

Installing Apache Maven on Mac OS X

Most of the OS X distributions prior to OS X Mavericks had Apache Maven preinstalled. To verify that you've got Maven installed in your system, try out the following command. If it does not result in a version, then it means you do not have it installed:

$ mvn –version

The following steps will guide you through the Maven installation process on Max OS X Yosemite:

1. First, we need to download the latest version of Maven. Throughout this book, we will use Maven 3.3.3, which was the latest version at the time of writing this book. Maven 3.3.3 ZIP distribution can be downloaded from http://maven.apache.org/download.cgi.
2. Unzip the downloaded ZIP file into /usr/share/java. You need to have the sudo privileges to execute this:

   $ sudo unzip  apache-maven-3.3.3-bin.zip -d /usr/share/java/
   

3. In case you already have Maven installed in your system, use the following command to unlink. /usr/share/maven is only a symlink to the directory where Maven is installed:

   $ sudo unlink /usr/share/maven
   

4. Use the following command to create a symlink to the latest Maven distribution that you just unzipped. You need to have the sudo privileges to execute this:

   $ sudo ln -s /usr/share/java/apache-maven-3.3.3  /usr/share/maven
   

5. Use the following command to update the value of the PATH environment variable:

   $ export PATH=$PATH:/usr/share/maven/bin
   

6. Use the following command to update (or set) the value of the M2_HOME environment variable:

   $ export M2_HOME=/usr/share/maven
   

7. Verify the Maven installation with the following command:

   $ mvn -version
     Apache Maven 3.3.3 (7994120775791599e205a5524ec3e0dfe41d4a06;   2015-04-22T04:57:37-07:00)
     Maven home: /usr/share/maven
     Java version: 1.7.0_75, vendor: Oracle Corporation
     Java home:   /Library/Java/JavaVirtualMachines/jdk1.7.0_75.jdk/Contents/Hom  e/jre
     Default locale: en_US, platform encoding: UTF-8
     OS name: "mac os x", version: "10.10.2", arch: "x86_64",   family: "mac"
   

8. If you get the following error while running the preceding command, it means you have another version of Maven running in your system, and the PATH system variable includes the path to its bin directory. If that is the case, you need to clean out the value of the PATH system variable by removing the path to the old Maven installation:

     -Dmaven.multiModuleProjectDirectory system property is not   set. Check $M2_HOME environment variable and mvn script match.
   

Note

Maven can also be installed on Mac OS X with Homebrew. This video explains the installation process in detail—

https://www.youtube.com/watch?v=xTzLGcqUf8k

Installing Apache Maven on Microsoft Windows

First, we need to download the latest version of Maven. Apache Maven 3.3.3 ZIP distribution can be downloaded from http://maven.apache.org/download.cgi. Then, we need to perform the following steps:

1. Unzip the downloaded ZIP file into the C:\Program Files\ASF directory.
2. Set the M2_HOME environment variable and point it to C:\Program Files\ASF\apache-maven-3.3.3.
3. Verify the Maven installation with the following command on the command prompt:

   mvn –version
   

Note

To know more about how to set the environment variables on Microsoft Windows, refer to http://www.computerhope.com/issues/ch000549.htm.