title: how to open a jar file in Eclipse
body: <p>I downloaded a demo jar file, and would like to open it in eclipse. What I did is</p>
  
  <blockquote>
    <p>import->Existing projects into workspace ->select archive file</p>
  </blockquote>
  
  <p>However, the eclipse returns "No projects are found to import".</p>
  
  <p>As command line, I type </p>
  
  <blockquote>
    <p>java -jar projectDemo.jar</p>
  </blockquote>
  
  <p>This jar file just functions well. So it seems to me that jar file itself is OK, but how can I open it in Eclipse and modify this demo code? Thanks.</p>