Class Utils

java.lang.Object

Utils

public class Utils
extends java.lang.Object

A collection of public static utility methods.

Constructor Summary

Constructors

Constructor and Description
Utils()

Method Summary

Modifier and Type	Method and Description
static void	main(java.lang.String[] args) A test driver main() method for this class.
static void	pause() The default version, with no indentation, no pause number, no special message, so only the "Press Enter to continue ...
static void	pause(int indentLevel) The version in which the "Press Enter to continue ...
static void	pause(int indentLevel, java.lang.String message) The version in which the "Press Enter to continue ...
static void	pause(int indentLevel, java.lang.String message, int pauseNumber) Causes the program to pause and wait for the user to press Enter to continue, with default values for the indentation level, the message supplying any additional information to the user, and the pause number.
static boolean	userSaysYes(java.lang.String question) Gets the user's yes-or-no answer to a single question.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Utils

public Utils()

Method Detail

pause

public static void pause(int indentLevel,
                         java.lang.String message,
                         int pauseNumber)

Causes the program to pause and wait for the user to press Enter to continue, with default values for the indentation level, the message supplying any additional information to the user, and the pause number.

Parameters:

indentLevel - The number of spaces to indent the first line of each part of the output from the left margin.

message - The message to be displayed, giving the reason for this particular pause, if such a message is supplied.

pauseNumber - The number of this particular pause, if pauses are being numbered.

Pre-conditions:

• The input stream is empty.

Post-conditions:

• Each line of output produced by this function is automatically indented indentLevel spaces, except for the second and any subsequent lines of the text in message, which require a newline character to start a new line.
• If pauseNumber is 0 (the default value), there is no corresponding output, while if pauseNumber is any positive value (6 for example), a line like the following has been displayed as the first line of output:

  This is pause #6.
  

• If message is non-empty, its content has been displayed next, starting on the next line. An automatic newline is also inserted following the text of message, so the text of message itself need not (though it may) contain one or more newline characters.
• As the last line of output, in all cases, the message

  Press Enter to continue ...
  

  has been displayed, with the cursor at the end of the line, positioned one space beyond the ellipsis.
• The user has pressed Enter.

pause

public static void pause(int indentLevel,
                         java.lang.String message)

The version in which the "Press Enter to continue ... " prompt is indented, as is the first line (but not subsequent lines) of an additional message, but there is no pause number.

Parameters:

indentLevel - The number of spaces to indent the first line of each part of the output from the left margin.

message - The message to be displayed, giving the reason for this particular pause, if such a message is supplied.

pause

public static void pause(int indentLevel)

The version in which the "Press Enter to continue ... " prompt is indented, but there is no additional message and no pause number.

Parameters:

indentLevel - The number of spaces to indent the first line of each part of the output from the left margin.

pause

public static void pause()

The default version, with no indentation, no pause number, no special message, so only the "Press Enter to continue ... " prompt is output.

userSaysYes

public static boolean userSaysYes(java.lang.String question)

Gets the user's yes-or-no answer to a single question.

Parameters:

question - Text of the question the user is asked, including the question mark.

Returns:

true if the user answers with a y or Y to the question asked, and false otherwise.

Pre-conditions:

• question has been initialized.
• The standard input stream is empty.

Post-conditions:

The text in question has been displayed, followed by (y/[n]) and the user has responded by entering a character and pressing Enter. The value true is returned if the user responds positively to the question asked by entering a y or a Y. Entering any other letter or word, as well as simply pressing the Enter key, will be interpreted as a negative response and the return value will be false. The use of [n] as part of the user prompt is meant to indicate to the user that simply pressing Enter will generate a (default) response of "no". This is a convention of reasonably widespread use in console applications.

main

public static void main(java.lang.String[] args)

A test driver main() method for this class.

Parameters:

args - The array of command-line parameters.