title: "Could not find main method from given launch configuration" when using Java+Scala+Slick2D
body: <p>I've got a project in which I'm using Java+Scala+Slick2D.</p>
  
  <p>The project itself runs well when launched from within eclipse. But when I try to make a jar file, it just refuses to work. Here's the error I keep getting when trying to export it as a Runnable jar:</p>
  
  <p><img src="https://i.stack.imgur.com/OdiNM.jpg" alt="enter image description here"></p>
  
  <p>And if I try to export into just a Jar file, it's unable to find the Main Class:</p>
  
  <p><img src="https://i.stack.imgur.com/EUoIq.jpg" alt="enter image description here"></p>
  
  <p>There is, of course, a main class in game.TicTacGame. But it refuses to acknowledge it. I tried creating an executable with a simple Hello World project and it worked fine. It even detects the main class. Why is Eclipse not detecting the main class in this case?</p>
  
  <p>PS: I've also tried extracting the .jar file created, editing the manifest.mf file to add the Main-Class: game.TicTacGame, enter two new lines and recreate the jar. Then it gives me a corrupted jar file error.</p>
  
  <p>I'm at my wits end and would appreciate any help in this regard. I'm using Windows 7 x64 with Eclipse Juno, Java 1.7 and Scala 2.10</p>
  
  <p>Edit: The Main class is in Java</p>