1. Getting Started with Maven

Create Java Project

mvn archetype:generate
-DgroupId=org.yourcompany.project
-DartifactId=application

Create Web Project

mvn archetype:generate
-DgroupId=org.yourcompany.project
-DartifactId=application
-DarchetypeArtifactId=maven-archetype-webapp

Create Archetype from Existing Project

mvn archetype:create-from-project

Main Phases

clean — delete target directory
validate — validate, if the project is correct
compile — compile source code; classes stored in target/classes
test — run tests
package — package compiled code as JAR/WAR
verify — verify the package is valid and meets quality criteria
install — install the package into the local repository
deploy — copy the final package to the remote repository

2. Useful Command Line Options

Skip Tests

-DskipTests=true  — compiles tests, but skips running them

Skip Test Compilation

-Dmaven.test.skip=true  — skips compiling and running tests

Parallel Builds

-T 4  — 4 threads; a decent default
-T 2C — 2 threads per CPU

Resume / Select Modules

-rf, --resume-from — resume build from specified project
-pl, --projects — build only specified modules
-am, --also-make — build required dependent modules too

Other Useful Options

-o, --offline — work offline
-X, --debug — enable debug output
-P, --activate-profiles — comma-delimited profiles to activate
-U, --update-snapshots — check for updated remote dependencies
-ff, --fail-fast — stop at first failure

3. Essential Plugins

Help Plugin

mvn help:describe — describes plugin attributes
mvn help:effective-pom — displays the effective POM with active profiles factored in

Dependency Plugin

mvn dependency:analyze — analyzes project dependencies
mvn dependency:tree — prints the dependency tree

Compiler Plugin

Compiles Java code and can set the language level.

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-compiler-plugin</artifactId>
  <version>3.6.1</version>
  <configuration>
    <source>1.8</source>
    <target>1.8</target>
  </configuration>
</plugin>

Version Plugin

Used to manage artifact versions in a project's POM.

Wrapper Plugin

Helps ensure Maven users have everything required for the build.

Spring Boot Plugin

Compiles a Spring Boot application and builds an executable fat JAR.

Exec Plugin

General-purpose plugin that can run arbitrary commands.