Java How to Program Fourth Edition - DCC

Chapter 6 Methods 307
6.16 Write a method multiple that determines for a pair of integers whether the second integer
is a multiple of the first. The method should take two integer arguments and return true if the second
is a multiple of the first and false otherwise. Incorporate this method into an applet that inputs a
series of pairs of integers (one pair at a time using JTextFields). [Note: Register for event handling
on only the second JTextField. The user should interact with the program by typing numbers
in both JTextFields and pressing Enter only in the second JTextField.]
6.17 Write a method isEven that uses the modulus operator to determine if an integer is even.
The method should take an integer argument and return true if the integer is even and false otherwise.
Incorporate this method into an applet that inputs a series integers (one at a time using a
JTextField).
6.18 Write a method squareOfAsterisks that displays a solid square of asterisks whose side
is specified in integer parameter side. For example, if side is 4, the method displays
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Incorporate this method into an applet that reads an integer value for side from the user at the keyboard
and performs the drawing with the squareOfAsterisks method. Note that this method
should be called from the applet’s paint method and should be passed the Graphics object from
paint.
6.19 Modify the method created in Exercise 6.18 to form the square out of whatever character is
contained in character parameter fillCharacter. Thus, if side is 5 and fillCharacter is
“#”, the method should print
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6.20 Use techniques similar to those developed in Exercise 6.18 and Exercise 6.19 to produce a
program that graphs a wide range of shapes.
6.21 Modify the program of Exercise 6.18 to draw a solid square with the fillRect method of
the Graphics class. Method fillRect receives four arguments: x-coordinate, y-coordinate,
width and height. Allow the user to input the coordinates at which the square should appear.
6.22 Write program segments that accomplish each of the following tasks:
a) Calculate the integer part of the quotient when integer a is divided by integer b.
b) Calculate the integer remainder when integer a is divided by integer b.
c) Use the program pieces developed in parts a) and b) to write a method displayDigits
that receives an integer between 1 and 99999 and prints it as a series of digits, each
pair of which is separated by two spaces. For example, the integer 4562 should be printed
as
4 5 6 2
d) Incorporate the method developed in part c) into an applet that inputs an integer from an
input dialog and invokes displayDigits by passing the method the integer entered.
Display the results in a message dialog.
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