title: eclipse java.lang.NoClassDefFoundError for nonexisting class
body: <p>When I try to compile my project I got this error:</p>
  
  <pre><code>    java.lang.NoClassDefFoundError: me/hansolox1/tetris/test
  Caused by: java.lang.ClassNotFoundException: me.hansolox1.tetris.test
      at java.net.URLClassLoader$1.run(Unknown Source)
      at java.security.AccessController.doPrivileged(Native Method)
      at java.net.URLClassLoader.findClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
  Exception in thread "main" 
  </code></pre>
  
  <p>but class me.hansolox1.tetris.test I deleted beafore I added real code to project.
  it's first time I see an error like this... Please help!</p>
  
  <p>EDIT:</p>
  
  <p>I have deleted test class but new class with method 'main':</p>
  
  <pre><code>package me.hansolox1.tetris;
  
  import org.newdawn.slick.AppGameContainer;
  import org.newdawn.slick.GameContainer;
  import org.newdawn.slick.SlickException;
  import org.newdawn.slick.state.StateBasedGame;
  
  public class tetris extends StateBasedGame {
      public static final int MAINMENU = 0;
      public static final int TETRIS = 1;
  
      public tetris(){
          super("Tetris!");
      }
  
      @Override
      public void initStatesList(GameContainer arg0) throws SlickException {
          this.addState(new MainMenu(MAINMENU));
          this.addState(new MainState(TETRIS));
      }
      public static void main(String[] args) throws SlickException{
          AppGameContainer app = new AppGameContainer(new tetris());
  
          app.setDisplayMode(800, 600, false);
          app.start();
      }
  }
  </code></pre>
  
  <p>I'm using slick2d engine...</p>
  
  <p>EDIT2: I also have tried cleanup</p>