title: Intellij setup for Java graphics
body: <p>How to write the BouncingBall program in Intellij . . . I'm trying to use multiple sources of information to get a good grasp of Java. To this end, I've taken the Udacity Intro to Java course, downloaded Intellij-IDEA, use the Sololearn App, and have been watching a series of lectures posted to Youtube by Stanford University. I'm trying to copy the program from Mehran Sahami's tenth lecture in the series <a href="https://www.youtube.com/watch?v=YpZCKVG4s5k&amp;t=1995s" rel="nofollow noreferrer">https://www.youtube.com/watch?v=YpZCKVG4s5k&amp;t=1995s</a> but can't get it to run. I'm assuming that there are elements required for it to run that are not being properly imported or invoked. But, being a novice, at both Java and Intellij, I'm not sure where to start. </p>
  
  <p>Here's how my code starts, anything obvious leap out? Is anything here calling for files or classes I need to install into the source or project folders, JDK, or elsewhere?</p>
  
  <pre><code>&lt;import acm.program.*.r[]
      public class BouncingBall extends GraphicsProgram{
         private static final int DIAM_BALL=30;
         private static final double GRAVITY=3;
         private static final int DELAY=50;
         private static final double X_START=DIAM_BALL/2;
         private static final double Y_START=100;
  </code></pre>
  
  <p>Certain terms in the IDE are shown in red and the tooltip indicates "Cannot resolve symbol(or method)". This also suggests to me that the tool cannot reach the required classes or files. So . . . how do I fix that? </p>
  
  <p>Thanks in advance!</p>