Chapter 6, Problem 1PP

Define a utility class for displaying values of type double. Call the class DoubleOut. Include all the methods from the class DollarFormat in Listing 6.14, all the methods from the class OutputFormat of Set-Test Question 30, and a method called scienceWrite that displays a value of type double using e notation, such as 2.13e-12. (This e notation is also called scientific notation, which explains the method name) When displayed in e notation, the number should appear with exactly one nonzero digit before the decimal point–unless the number is exactly zero. The method scienceWrite will not advance to the next line. Also add a method called scienceWriteln that is the same as scienceWrite except that it does advance to the next line. All but the last two method definitions can simply be copied from the text (or more easily from the source code for this book that is available on the Web.). Not that you will be overioading the method names write and writeln.

Write a driver program to test your method scienceWriteln. This driver program should use a stub for the method scienceWrite. (Note that this means you can write and test scienceWriteln before you even write scienceWrite.) Then write a driver program to test the method scienceWrite. Finally, write a program that is a sort of super driver program that take a double value as input and then displays it using the two writeln methods and the scienceWriteln method. Use the number 5 for the number of digits after the decimal point when you need to specify such a number. This super driver program should allow the user to repeat this testing with additional numbers of type double until the user is ready to end the program.