title: Using Java for light control
body: <p>when reading Eckel's Thinking in Java, I found design for controlling Greenhouse. It really struck me, since he was mentioning in comment lines "here put the hardware code for controlling light" and stuff, and I want to know - how would I make such a simple thing, as controlling physical light, or traffic light with Java program?</p>
  
  <p>How would I connect light to PC and power it, through software control?</p>
  
  <p>I believe assembly language with some microcontroller is the way, but I do not intend to learn assembly language yet, so I want to know if there's possibility to do this with Java?</p>
  
  <p>Thanks,
  M.</p>