Java - Build Run Maven Project Command Line

ArcheType for simple Java Project

Setting up a maven project on your favorite IDE can be time consuming and slow. Many developers prefer to setup maven project from command line use their favorite text editor to write code. Maven is a build tool and setting up a boilerplate seed project shouldn't be an issue.

#generate simple java maven project
mvn archetype:generate -DgroupId=com.yourcompany -DartifactId=myproject -DarchetypeArtifactId=maven-archetype-quickstart -DinteractiveMode=false

This will create a java project (not web) with package com.yourcompany and folder name as myproject. Skips the interactive steps. The generated maven project will include a basic structure for the java project along with test packages. You can later add the JUnit dependency for writing tests.

The package name of your project becomes the groupId and the name of the project is artifactId.

Maven Build command

Maven comes with predefined goals.

The compile goal will

• download all the dependencies
• compile the project
• and generate the target folder.

#compile the project and generate target folder
mvn compile

If changes are made to the code, mvn compile needs to be executed again before calling exec.

The following command builds the maven project and installs it into local maven repository.

mvn install

Before that if you wish to clean the target/ folder. Run the following maven build command

mvn clean install

If you are looking to package the project, then you should run

mvn package

Maven Skip Test Command

If you are executing any of the above build or package maven goals, you may want to skip tests. JUnit tests written in your maven project can be skipped by adding the maven.test.skip=true option

mvn -Dmaven.test.skip=true package

Maven Run Command

Maven's exec plugin can be used to run any of the main class generated in the target folder. Here the main class being com.mycompany.App

#execute the project
mvn exec:java -Dexec.mainClass=com.mycompany.App

Note: You cannot execute the maven project with Exec plugin without the compile step. Since this step checks the target directory for the classes to call.

If you would like to pass parameters, you can use exec.args option as follows.

mvn exec:java -Dexec.mainClass=com.mycompany.App -Dexec.args="foo bar"

Maven can be configured with plugins to run the main class

Running Unit Tests

If you want to run tests, run the test goal. It will run all the tests created using the surefire plugin.

mvn test

You can also run a single test file or a particular method inside a test file as follows.

mvn test -Dtest=com.mycompany.AppTest#testMethod

Running maven commands from batch file

When running maven commmands from the batch file, it may stop after executing the maven build, in that case use the call before maven command.

cd ..\parser
call mvn clean install
move .\target\*.jar ..\server\lib

Running maven from another directory

In the above batch file, we had first changed our directory to the project directory. If we wish to execute the maven command without changing the project directory we can use the -f option and reference the pom.xml of the target project from anywhere.

mvn -f parser/pom.xml clean install

Misc

In case you want to move the project or upload it over ftp or somewhere. Before creating the zip of your code, call mvn clean to clean-up the target directly. Helps to keep the size low.:)

If you are pushing your code to a git repository, consider adding Maven .gitignore to it.

.gitignore

target/

This will exclude the target folder from the git repo.

If you are looking forward to generate webapp with maven, read Build and Deploy maven project with embedded tomcat.