Maven Useful Commands

What is Maven?

Maven is a powerful build automation and project management tool primarily used for Java projects. This guide covers frequently used Maven commands for dependency management, debugging, and troubleshooting.

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🧩 Install Local JAR

Manually install a dependency when it cannot be downloaded from Maven Central (Oracle, IBM, internal JARs).

mvn install:install-file \
  -Dfile=ojdbc8.jar \
  -DgroupId=com.oracle.database.jdbc \
  -DartifactId=ojdbc8 \
  -Dversion=19.3.0.0 \
  -Dpackaging=jar

Common Use Cases

• Oracle JDBC drivers
• Telecom / vendor SDKs
• Internal utilities not published yet

🏢 Deploy to Nexus/Artifactory

Publish any standalone JAR to your internal Maven repository.

mvn deploy:deploy-file \
  -Durl=http://nexus.myorg.com/repository/maven-releases/ \
  -DrepositoryId=nexus \
  -Dfile=my-util.jar \
  -DgroupId=com.myorg.util \
  -DartifactId=my-util \
  -Dversion=1.0.0 \
  -Dpackaging=jar

Requirements

• Configure repositoryId in settings.xml
• Ensure credentials are set up
• Use releases repo for stable versions

🔍 Debug Dependencies

View Full Tree

mvn dependency:tree

Filter Specific Dependency

mvn dependency:tree -Dincludes=com.fasterxml.jackson.core

Verbose Mode

mvn dependency:tree -Dverbose

Show Conflicts

mvn dependency:tree -Dverbose | grep "omitted for conflict"

🔄 Force Update Dependencies

Force Maven to download latest SNAPSHOT and release versions.

mvn clean install -U

When to Use

• SNAPSHOT dependencies not updating
• Corrupted local repository
• After changing remote repository URLs

🧱 Build Specific Module

Build only a specific module in a multi-module project.

mvn -pl module-name -am clean install

Flags

Flag	Description
-pl	Project list - specify module(s)
-am	Also make - build required dependencies
-amd	Also make dependents - build dependent modules

Examples

# Build single module
mvn -pl service-api clean install

# Build multiple modules
mvn -pl service-api,service-impl clean install

# Build module and dependents
mvn -pl shared-utils -amd clean install

🚫 Skip Tests

Skip Test Execution

mvn clean install -DskipTests

Skip Compilation & Execution

mvn clean install -Dmaven.test.skip=true

Difference

• skipTests: Compiles but doesn’t run
• maven.test.skip: Skips everything

🧪 Run Specific Tests

Single Test Class

mvn -Dtest=LoginTest test

Pattern Matching

mvn -Dtest=User*Test test

Specific Test Method

mvn -Dtest=LoginTest#shouldLoginWorks test

Multiple Tests

mvn -Dtest=LoginTest,UserTest test

🧹 Fix Corrupted Dependencies

Delete Specific Library

rm -rf ~/.m2/repository/com/oracle

Purge Entire Local Repo

mvn dependency:purge-local-repository

Re-download All

mvn dependency:purge-local-repository -DreResolve=true

📜 Effective POM

View the final POM after all inheritance and interpolation.

mvn help:effective-pom

Save to File

mvn help:effective-pom > effective-pom.xml

Why Use It

• Debug property resolution
• See inherited configurations
• Verify profile activation

🔧 List Active Plugins

mvn help:effective-pom | grep "<plugin>"

All Available Plugins

mvn help:describe -Dplugin=compiler

🐞 Debug Mode

Enable debug logging for CI/CD troubleshooting.

mvn clean install -X

Show Stack Traces

mvn clean install -e

🔐 Fix SSL/Certificate Issues

Import Certificate

keytool -import -alias nexus \
  -file nexus.crt \
  -keystore $JAVA_HOME/jre/lib/security/cacerts \
  -storepass changeit

Disable SSL Verification (Development Only)

mvn clean install -Dmaven.wagon.http.ssl.insecure=true \
  -Dmaven.wagon.http.ssl.allowall=true

🧵 Work with Profiles

List All Profiles

mvn help:all-profiles

Show Active Profiles

mvn help:active-profiles

Build with Profile

mvn clean install -Pdev

Multiple Profiles

mvn clean install -Pdev,fast-tests

📦 Offline Mode

Download all dependencies for offline use.

mvn dependency:go-offline

Build Offline

mvn clean install -o

Use Cases

• CI/CD with dependency caching
• Development without internet
• Air-gapped environments

🎯 Clean Specific Targets

Clean Generated Sources

mvn clean:clean@clean-generated

Clean Without Deleting Logs

mvn clean -Dclean.exclude=logs/**

Deep Clean

mvn clean install -U -DskipTests