title: Add jar file to Eclipse project with relative path
body: <p>I have a Java project in Eclipse. How can I add a jar file to the eclipse project with a relative path? That means the jar file is stored in the project directory and the project should still work when its whole directory is moved.</p>
  
  <p>Using external jar works, but this is not what I want!</p>
  
  <p>I also know that I should use 'Add jar' and not 'Add external jar'. But 'Add external jar' shows my selectable jar file and 'Add jar' does not. Why??
  When I change the absolute path in the class file to relative path the project does not work anymore.</p>
  
  <p>How the hell can I make Eclipse referring a jar relatively and not absolutely. I also wonder why this is so hard to do.</p>