title: How do I open and run a compiled Java file?
body: <p>How do I open a .class or .jar file within a Java program?
  (remember that .jar files may have more than one class with main(String[] args) method)</p>
  
  <p>(individual question from <a href="https://stackoverflow.com/questions/4002976/ide-style-program-running">IDE-Style program running</a> )</p>