Learn Java with Math: Using Fun Projects and Games

© Ron Dai 2019

R. DaiLearn Java with Mathhttps://doi.org/10.1007/978-1-4842-5209-3_29

29. Common Pitfalls

Ron Dai¹ 

(1)

Seattle, WA, USA

 

In this chapter, I want to share several pieces of code that expose common issues in coding practice. Using these examples to diagnose root causes will help improve your understanding. I recommend thinking independently before seeking answers. You may find some hints in the final chapter.

Lab Work

1. 1.
   Anything wrong here?

   String aAsString;

   String bAsString;

   Scanner user_input = new Scanner(System.in);

   System.out.println("a=");

   aAsString = user_input.next();

   a = Integer.valueOf(aAsString);

   System.out.println("b=");

   bAsString = user_input.next();

   b = Integer.valueOf(bAsString);
    
2. 2.
   Any errors here?

   public class TestArray {

          public ...