Run-time errors

• If an exception occurs when you try and run the program, again, look at the details written to the screen -- the line number and the type of exception thrown -- then examine this area of your source code. You may have written code that tries to go beyond the end of an array for example.

• If you suspect a particular block of code may be causing problems try surrounding it with the longer form of comment /*/ which effectively removes it from your program without lots of unnecessary deleting. Then compile (and run) the program again to see if the error/exception still occurs -- if it doesn't then the problem lies within the code that was commented out. This method can be tried with both compiler and runtime errors.

• So long as the program compiles okay, you can add System.out.println(...); to your program at strategic points to determine how far the program gets before the exception is thrown. This allows you to narrow down on where the problem code must be.