From: Java Programming: From Problem Analysis to Program Design, 5th ed.

Ch. 11, page 782, Problem Exercise 7 (an extension of 6PE):

The Calculator programming example of this chapter is designed to perform operations on integers. Write a similar program that can be used to perform operations on decimal numbers. (Note: If division by zero occurs with values of the int data type, the program throws a division by zero exception. However, if you divide a decimal number by zero, Java does not throw the division by zero exception; it returns the answer as infinity. However, if division by zero occurs, your calculator program must output the message ERROR: / by zero.)