In previous article, we have integrated Apache Maven – a popular build tool with Eclipse IDE

By default, M2_REPO classpath variable doesn’t come added with Eclipse IDE in older versions

With newer versions like Kepler, Luna or Mars OR after integrating maven plugins (m2eclipse) with Eclipse IDE, M2_REPO classpath variable gets added –> pointing to default locations (for example c:\Users\<user_name>\.m2\repository) and this variable is non-modifiable –> means we can’t edit it to point to the correct local maven repository

Lets us concentrate on setting M2_REPO classpath variable and in the succeeding article we will see how can we edit this non-modifiable variable and correct it to point local maven repository

1. Setting M2_REPO classpath variable in IDE :

There are two ways

• Manual approach via Eclipse IDE
• Maven command approach

1.1 Manual approach via Eclipse IDE

Step 1: Open Eclipse IDE –> Windows –> Preferences

Step 2: Go to Java –> Build Path –> Classpath Variables

Step 3: Click New –> Enter following details –> Click OK

Name: M2_REPO
Path: D:\M2_HOME\.m2\repository (pointing to local maven repository location)

Step 4: Done “M2_REPO” classpath variable added to Eclipse IDE successfully

That’s all !! completed walking to Way-1. Lets us move on to check the Way-2

1.2 Maven command approach

Step 1: Run below maven cmd in Windows command prompt

Syntax:

mvn -Declipse.workspace="eclipse_workspace_location" eclipse:configure-workspace

Example:

mvn -Declipse.workspace="D:\WORKSPACE\TEST_WORKSPACE" eclipse:configure-workspace

Note: Before moving to Step 2 to verify, close eclipse IDE if it’s already opened and open again (restart required to take effects of new changes)

Step 2: Verify …..Whether M2_REPO classpath variable added or not –> pointing to correct local maven repository location

That’s pretty clear now, we can add M2_REPO classpath variable using mvn command

2. Useful Eclipse IDE shortcuts :

• Eclipse IDE – How to show line numbers ?
• Eclipse IDE – How to GO TO any line number directly ?
• Eclipse IDE – How to remove unused imports ?
• Eclipse IDE – How to clean project ?
• Eclipse IDE – How to build Java project automatically ?
• Eclipse IDE – How to comment and un-comment line & block ?
• Eclipse IDE – How to generate constructor using fields ?
• Eclipse IDE – How to generate getters and setters ?
• Eclipse IDE – How to search files ?
• Eclipse IDE – How to locate methods in Java file ?
• Eclipse IDE – How to open editor using CTRL + E ?
• Eclipse IDE – Java compiler compliance level issue

Related Articles:

• Eclipse + Maven – Integration
• Eclipse + Maven – How to import Maven project with pom.xml ?
• Eclipse + Maven – Setting M2_REPO classpath variable in IDE
• Eclipse + Maven – M2_REPO is Non Modifiable
• Eclipse + Maven – Creating and exploring projects using archetypes
• Eclipse + Maven – Converting Web project to Maven project
• Eclipse + Maven – mvn eclipse:eclipse command
• Eclipse + Maven – Plugin execution not covered by lifecycle configuration
• Apache Maven – Introduction
• Apache Maven – Install on Windows 7 OS
• Apache Maven – Settings.xml explanation
• Apache Maven – Proxy setting explanation
• Apache Maven – pom.xml explanation
• Apache Maven – Plugins explanation
• Apache Maven – Changing default Maven repository location in Windows 7 OS
• Apache Maven – Local, Central and Remote Repositories
• Apache Maven – Installing custom library into local repository
• Apache Maven – Transitive dependencies explanation
• Apache Maven – Exclusion of Transitive dependencies
• Apache Maven – Dependency Scopes
• Apache Maven – Skipping unit test using surefire plugin
• Apache Maven – Exclusions and Inclusions of unit test
• Apache Maven – offline execution
• Apache Maven – Co-ordinates explained

References:

• http://maven.apache.org/guides/mini/guide-ide-eclipse.html
• http://maven.apache.org/guides/mini/guide-ide-eclipse.html#Maven_2_repository

Happy Coding !!
Happy Learning !!