title: Intellij IDEA how to run a class not the entire project?
body: <p>is there a way to run (not only compile) a single class (with a main method) instead to run the entire project as does Intellij IDEA?</p>
  
  <p>And, is it possible to open different projects in the same window instead to opening them in a new window or in place of the current project?</p>