What does the method do?  Are there pre- and post-conditions (i.e. is  
there some state that you can query before and after invoking it in order  
to determine if it worked properly)?

Dan.

On Dec 16, 9:45 am, akhileshkokarde...@gmail.com wrote:

Test its effect upon the rest of the system.

e.g.

Here's a clock class with Tick method that does not return anything....

import junit.framework.TestCase;

public class ClockTest extends TestCase {

 public void testTickIncrementsTheTime() {
   Clock clock = new Clock(0, 1);

   clock.tick();

   assertEquals("Wrong time!", "0:2", clock.getTime());
 }

 class Clock {
   private int minutes;
   private int seconds;

   public Clock(int mins, int secs) {
     minutes = mins;
     seconds = secs;
   }

   public String getTime() {
     return minutes + ":" + seconds;
   }

   public void tick() {
     seconds++;
   }
 }

}

Andrew

One would assume that it has a side effect. Test for the side effect.
E.g. if the method is a setter, call the getter afterward in your unit
test and check that it behaved appropriately. If it's something more
complicated, it will be trickier to manage, and may even require
checking a property sheet or disk file has been altered appropriately.

1. Test pre and post conditions.
2. Take a look at Mock Objects.

Richard