Its a simple but tricky process. There are some common mistakes that a beginner usually do, significantly the one, not coming from Java background. So here is the step by step process to configure iDempiere source code and avoid common mistakes.
Prerequisites of iDempiere are as follow:
Windows and Ubuntu both works fine
Environment variables of Java, Maven and Postgre SQL must be configured manually, if not done by OS by default.
Now clone the iDempiere source code from GitHub repository.
Note: The name of the directory, in which source code is placed should not contain any space or special character. Otherwise, Maven will not verify some of the files and source code will never be deployed.
Now open Eclipse and Click the Windows in navigation bar -> Preferences -> Now open sub-menu of Maven and click Discovery -> Open Catalog and type ‘Tycho’ in search field. You will see Tycho Configurator as result. Check the option and click Finish. Do some Next Next Next and acccept the T&C. Click finish again and let it install. Restart Eclipse.
Open the source code directory and run (mvn verify) command using terminal, so that all maven dependencies will be downloaded.
Now open eclipse -> Turn off build automatically -> click Import and select Existing Maven Project option. Now select the same directory in which source code is placed.
After importing eclipse create some changes to the workspace, you can discard those changes at this point via right click on the projects and choosing Replace With > HEAD Revision. Note: This is an important step which begineers ignore. You need to click and Revise every single project in Eclipse.
Now you need to import Source Target Platform file. Click Import -> General -> Existing Java Project -> and select org.idempiere.p2.targetplatform. Click finish and open the file org.idempiere.p2.targetplatform.target within the project just imported org.idempiere.p2.targetplatform. WAIT UNTIL ECLIPSE FINISH DOWNLOADING.
At Target Editor, click the “Set as Active Target Platform” link. Click the “Reload” button if some download fail. Turn on Build Automatically. Restart Eclipse.