Maven Life Cycle

Introduction to Maven Life Cycle

Maven is completely based on the central concept of its build Life cycles. These build life cycles are the processes for building and distributing a particular project is clearly defined in each phase.

Maven Life Cycle

Maven defines 3 build lifecycles

1. Default Lifecycle
2. Clean Lifecycle
3. Site Lifecycle

Maven allows executing more than one lifecycle phase at a time. Each lifecycle is independent of each other. Life cycles have to be executed in sequential order as shown above. The complete maven lifecycle is defined in the ‘component.xml’ file in the core module. Each and every phase in lifecycle has a unique goal,

followings are the goals/tasks performed by lifecycle phases:

• Resource Preparation- copies resources like configuration files to build folder.
• Compilation- Compiling source codes.
• Packaging- Copying dependency JAR files to build folder.
• Runs unit tests.

Graphical Representation of Maven Lifecycle

1. Default Lifecycle

It is one of the most important Lifecycles of maven. In this lifecycle, Maven builds, tests and distributes. There are 22 phases/tasks performed in this lifecycle phase. Which are given in the following table?

S.No.	Task	Description
1	Validate	This phase validates the project and gathers all project related information.
2	Initialize	This phase initializes or sets properties for the build process.
3	Generate sources	Generates required source codes for compiling the project.
4	Process Sources	This phase copies and processes the sources into the destination directory and filters.
5	Generate resources	Generate resources included in the packages.
6	Process resources	Copies and processes the resources into a destination directory which are necessary for the packaging process.
7	Compile	Compiles the source code.
8	Process classes	This phase processes compiled source code or classes for optimization and byte code enhancement.
9	Generate-test-sources	Generates test source code which included in the compilation phase.
10	Process-test-source	Test the processes of the test source code and filter values.
11	Test-compile	Tests the compiled source code and copies into the destination directory.
12	Process-test-classes	Processes the generated files from the test compile phase.
13	Test	This phase tests code using a suitable unit testing method.
14	Prepare-package	This is the pre-packaging process. Performs necessary operation before the actual packaging process.
15	Package	Gathers all compiled files and packages in a specified format.
16	Pre-integration-test	This phase performs processes required before actual integration i.e. environment setup.
17	Integration-test	Actual integration testing phase. Deploys the necessary packages for integration testing.
18	Post-integration-test	In this phase, post-integration test processes are executed like clean up processes.
19	Verify	This phase verifies the packages for validity and quality criteria.
20	Install	This phase installs the packages into the local repository.
21	Deploy	This process deploys the final packages into a remote repository.
22	Validate	Validates the project code and packages for completion of the build process.

The following figure shows the process flow in the default lifecycle.

Example Maven commands in Default Lifecycle-

• >mvn compile
• >mvn validate
• >mvn clean compile
• >mvn package

2. Clean Lifecycle

In the Clean lifecycle phase, it performs the cleaning operation in which it deletes the build directory name target and its contents. To perform this operation we use command   >mvn clean. Clean lifecycle performs 3 types of clean operations-

1. Pre Clean
2. Clean
3. Post clean

The sequence of execution in clean commands.

When we invoke any clean command maven will execute a current clean command with its previous clean process.

3. Site Lifecycle

Mainly the site lifecycle handles the creation of project site documentation.

• Maven Site Lifecycle phases.

1. Pre-site
2. Site
3. Post-site
4. Site-deploy

Graphical Representation of Site Lifecycle Execution

Sr.No.	Name	Description
1	Pre-site	This phase executes the processes before the actual site.
2	Site	This phase executes the actual site documentation process.
3	Post-site	This phase executes the processes required to finalize the site generation and preparation for site deployment.
4	Site-deploy	Deploys specific site generated documentation into the webserver.

Components.xml file

<Component-set>
<components>
<component>
<role>org.apache.maven.lifecycle.binding.LegacyLifecycleParsingTestComponent</role>
<implementation>org.apache.maven.lifecycle.binding.LegacyLifecycleParsingTestComponent</implementation>
<configuration>
<lifecycles>
<lifecycle>
<id>default</id>
<phases>
<phase>validate</phase>
<phase>initialize</phase>
<phase>generate-sources</phase>
<phase>process-sources</phase>
<phase>generate-resources</phase>
<phase>process-resources</phase>
<phase>compile</phase>
<phase>process-classes</phase>
<phase>generate-test-sources</phase>
<phase>process-test-sources</phase>
<phase>generate-test-resources</phase>
<phase>process-test-resources</phase>
<phase>test-compile</phase>
<phase>process-test-classes</phase>
<phase>test</phase>
<phase>prepare-package</phase>
<phase>package</phase>
<phase>pre-integration-test</phase>
<phase>integration-test</phase>
<phase>post-integration-test</phase>
<phase>verify</phase>
<phase>install</phase>
<phase>deploy</phase>
</phases>
</lifecycle>
<lifecycle>
<id>clean</id>
<phases>
<phase>pre-clean</phase>
<phase>clean</phase>
<phase>post-clean</phase>
</phases>
<default-phases>
<clean>org.apache.maven.plugins:maven-clean-plugin:clean</clean>
</default-phases>
</lifecycle>
<lifecycle>
<id>site</id>
<phases>
<phase>pre-site</phase>
<phase>site</phase>
<phase>post-site</phase>
<phase>site-deploy</phase>
</phases>
<default-phases>
<site>org.apache.maven.plugins:maven-site-plugin:site</site>
<site-deploy>org.apache.maven.plugins:maven-site-plugin:deploy</site-deploy>
</default-phases>
</lifecycle>
</lifecycles>
</configuration>
</component>
<component>
<role>org.apache.maven.lifecycle.mapping.LifecycleMapping</role>
<role-hint>test-mapping</role-hint>
<implementation>org.apache.maven.lifecycle.mapping.DefaultLifecycleMapping</implementation>
<configuration>
<lifecycles>
<lifecycle>
<id>default</id>
<phases>
<package>org.apache.maven.plugins………</package>
<install> org.apache.maven.plugins………</install>
<deploy> org.apache.maven.plugins………</deploy>
</phases>
</lifecycle>
</lifecycles>
</configuration>
</component>
<component>
<role>org.apache.maven.lifecycle.mapping.LifecycleMapping</role>
<implementation>org.apache.maven…….. </implementation>
<configuration>
<lifecycles>
<lifecycle>
<id>default</id>
<phases>
<package>
org.apache.maven.plugins………..
</package>
<install>org.apache.maven.plugins:maven-install-plugin:install</install>
<deploy>org.apache.maven.plugins:maven-deploy-plugin:deploy</deploy>
</phases>
</lifecycle>
</lifecycles>
</configuration>
</component>
</components>
</component-set>

Conclusion

Mavens default plugin and lifecycle allows the user to perform build actions very easily. Since all lifecycles configuration is maintained in components.xml it gives more consistency and structured project implementation. Using configuration file user can set the configuration /goals at the initial stage only more modification is not required in the pom.xml file. Considering all three lifecycles in configuration file individual lifecycle phases can be understood and differentiated very easily without much complexity.

Recommended Articles

This is a guide to Maven Life Cycle. Here we discuss an introduction, Maven defines 3 build lifecycles default, clean and site lifecycle in detail. You can also go through our other related articles to learn more –

1. Maven Plugins
2. Maven Interview Questions
3. Maven Commands
4. How to Install Maven