Question

When to use dependencymanagement and dependencies in the maven project. We are decomposing the existing project into 6 independent modules. Those are

Project-core
project-DAO
project-messages
project-services
project-testing
project-web

we are planning to have parent to all the above projects and place the common dependencies there. But we are not clear about where to use the <dependencyManagement> and <dependencies>. Please provide the valuable suggestions.

Thanks,
Anil Kumar C

Answer 1

Based on your ideas i would suggest the following folder structure:

+-- ProjectParent
      +-- Project-core
      +-- project-DAO
      +-- project-messages
      +-- project-services
      +-- project-testing
      +-- project-web 

which result into having a parent (ProjectParent) which should contain the dependencyManagement section to define the dependencies with their appropriate versions like this:

   <dependencyManagement>
     <dependencies>
       <dependency>
          <groupId>testng</groupId>
          <artifactId>testng</artifactId>
          <version>6.3.1</version>
          <scope>test</scope>
       </dependency>
       ...
     </dependencies>
   </dependencyManagement>

In every module you need the parent to reference to the parent:

com.company.project
project-parent
1.0.0-SNAPSHOT

and in a module you just define

 <dependencies>
   <dependency>
      <groupId>testng</groupId>
      <artifactId>testng</artifactId>
   </dependency>
   ..
 </dependencies>

to use the dependency from the parent.

This will simplify the update of dependencies, cause the version are located into a single point which means in the parent root and not distributed into different modules.