Chapter 5. Mavenizing your application
MTA provides the ability to generate an Apache Maven project structure based on the application provided. This will create a directory structure with the necessary Maven Project Object Model (POM) files that specify the appropriate dependencies.
Note that this feature is not intended to create a final solution for your project. It is meant to give you a starting point and identify the necessary dependencies and APIs for your application. Your project may require further customization.
5.1. Generating the Maven project structure
You can generate a Maven project structure for the provided application by passing in the --mavenize flag when executing MTA.
The following example runs MTA using the jee-example-app-1.0.0.ear test application:
$ <MTA_HOME>/bin/windup-cli --input /path/to/jee-example-app-1.0.0.ear --output /path/to/output --target eap:6 --packages com.acme org.apache --mavenize
This generates the Maven project structure in the /path/to/output/mavenized directory.
You can only use the --mavenize option when providing a compiled application for the --input argument. This feature is not available when running MTA against source code.
You can also use the --mavenizeGroupId option to specify the <groupId> to be used for the POM files. If unspecified, MTA will attempt to identify an appropriate <groupId> for the application, or will default to com.mycompany.mavenized.
5.2. Reviewing the Maven project structure
The /path/to/output/mavenized/<APPLICATION_NAME>/ directory contains the following items:
-
A root
POMfile. This is thepom.xmlfile at the top-level directory. -
A BOM file. This is the
POMfile in the directory ending with-bom. -
One or more application
POMfiles. Each module has itsPOMfile in a directory named after the archive.
The example jee-example-app-1.0.0.ear application is an EAR archive that contains a WAR and several JARs. There is a separate directory created for each of these artifacts. Below is the Maven project structure created for this application.
/path/to/output/mavenized/jee-example-app/
jee-example-app-bom/pom.xml
jee-example-app-ear/pom.xml
jee-example-services2-jar/pom.xml
jee-example-services-jar/pom.xml
jee-example-web-war/pom.xml
pom.xmlReview each of the generated files and customize as appropriate for your project. To learn more about Maven POM files, see the Introduction to the POM section of the Apache Maven documentation.
Root POM file
The root POM file for the jee-example-app-1.0.0.ear application can be found at /path/to/output/mavenized/jee-example-app/pom.xml. This file identifies the directories for all of the project modules.
The following modules are listed in the root POM for the example jee-example-app-1.0.0.ear application.
<modules> <module>jee-example-app-bom</module> <module>jee-example-services2-jar</module> <module>jee-example-services-jar</module> <module>jee-example-web-war</module> <module>jee-example-app-ear</module> </modules>
Be sure to reorder the list of modules if necessary so that they are listed in an appropriate build order for your project.
The root POM is also configured to use the Red Hat JBoss Enterprise Application Platform Maven repository to download project dependencies.
BOM file
The Bill of Materials (BOM) file is generated in the directory ending in -bom. For the example jee-example-app-1.0.0.ear application, the BOM file can be found at /path/to/output/mavenized/jee-example-app/jee-example-app-bom/pom.xml. The purpose of this BOM is to have the versions of third-party dependencies used by the project defined in one place. For more information on using a BOM, see the Introduction to the dependency mechanism section of the Apache Maven documentation.
The following dependencies are listed in the BOM for the example jee-example-app-1.0.0.ear application
<dependencyManagement>
<dependencies>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.6</version>
</dependency>
<dependency>
<groupId>commons-lang</groupId>
<artifactId>commons-lang</artifactId>
<version>2.5</version>
</dependency>
</dependencies>
</dependencyManagement>Application POM files
Each application module that can be mavenized has a separate directory containing its POM file. The directory name contains the name of the archive and ends in a -jar, -war, or -ear suffix, depending on the archive type.
Each application POM file lists that module’s dependencies, including:
- Third-party libraries
- Java EE APIs
- Application submodules
For example, the POM file for the jee-example-app-1.0.0.ear EAR, /path/to/output/mavenized/jee-example-app/jee-example-app-ear/pom.xml, lists the following dependencies.
<dependencies>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.6</version>
</dependency>
<dependency>
<groupId>org.jboss.seam</groupId>
<artifactId>jee-example-web-war</artifactId>
<version>1.0</version>
<type>war</type>
</dependency>
<dependency>
<groupId>org.jboss.seam</groupId>
<artifactId>jee-example-services-jar</artifactId>
<version>1.0</version>
</dependency>
<dependency>
<groupId>org.jboss.seam</groupId>
<artifactId>jee-example-services2-jar</artifactId>
<version>1.0</version>
</dependency>
</dependencies>