Class Keyboard

java.lang.Object
  |
  +--Keyboard

public class Keyboard

extends java.lang.Object

The Keyboard class, which simplifies input from a keyboard, is based on James Slack's Programming and Problem Solving with Java, published by Brooks/Cole. I have extended it to provide methods that take default values and, therefore, do not throw exceptions. The methods that read various types of floating point numbers have not yet been implemented.

The class file for Slack's original class is available online at

http://krypton.mankato.msus.edu/~slack/javabook/software.html

Author:

James Slack, Minnesota State University; modified by Alyce Brady

Constructor Summary

Keyboard()

Method Summary

static int	readInt() Waits for the user to type a number, and then returns that number as an int.
static int	readInt(int defaultValue) Waits for the user to type a number, and then returns that number as an int.
static int	readInt(java.lang.String prompt) Displays the given prompt, and then waits for the user to type a number, and then returns that number as an int.
static int	readInt(java.lang.String prompt, int defaultValue) Displays the given prompt, and then waits for the user to type a number, and then returns that number as an int.
static int	readInt(java.lang.String prompt, int lowValue, int highValue) Displays the given prompt, and then waits for the user to type a number, and then returns that number as an int.
static int	readInt(java.lang.String prompt, int lowValue, int highValue, int defaultValue) Displays the given prompt, and then waits for the user to type a number, and then returns that number as an int.
static long	readLong() Waits for the user to type a number, and then returns that number as a long.
static long	readLong(long defaultValue) Waits for the user to type a number, and then returns that number as a long.
static long	readLong(java.lang.String prompt) Displays the given prompt, and then waits for the user to type a number, and then returns that number as a long.
static long	readLong(java.lang.String prompt, int lowValue, int highValue) Displays the given prompt, and then waits for the user to type a number, and then returns that number as a long.
static long	readLong(java.lang.String prompt, int lowValue, int highValue, long defaultValue) Displays the given prompt, and then waits for the user to type a number, and then returns that number as a long.
static long	readLong(java.lang.String prompt, long defaultValue) Displays the given prompt, and then waits for the user to type a number, and then returns that number as a long.
static short	readShort() Waits for the user to type a number, and then returns that number as a short.
static short	readShort(short defaultValue) Waits for the user to type a number, and then returns that number as a short.
static short	readShort(java.lang.String prompt) Displays the given prompt, and then waits for the user to type a number, and then returns that number as a short.
static short	readShort(java.lang.String prompt, int lowValue, int highValue) Displays the given prompt, and then waits for the user to type a number, and then returns that number as a short.
static short	readShort(java.lang.String prompt, int lowValue, int highValue, short defaultValue) Displays the given prompt, and then waits for the user to type a number, and then returns that number as a short.
static short	readShort(java.lang.String prompt, short defaultValue) Displays the given prompt, and then waits for the user to type a number, and then returns that number as a short.
static java.lang.String	readString() Waits for the user to type a line, and then returns all characters the user typed as a string.
static java.lang.String	readString(java.lang.String prompt) Displays the given prompt, and then waits for the user to type a line, and then returns all characters the user typed as a string.
static java.lang.String	readString(java.lang.String prompt, java.lang.String defaultValue) Displays the given prompt, and then waits for the user to type a line, and then returns all characters the user typed as a string.

Methods inherited from class java.lang.Object

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

Constructor Detail

Keyboard

public Keyboard()

Method Detail

readString

public static java.lang.String readString()
                                   throws java.io.IOException

Waits for the user to type a line, and then returns all characters the user typed as a string.

Returns:

a String containing the characters the user typed in up to (not including) a newline.

Throws:

java.io.IOException - i/o error when reading from console

readString

public static java.lang.String readString(java.lang.String prompt)
                                   throws java.io.IOException

Displays the given prompt, and then waits for the user to type a line, and then returns all characters the user typed as a string.

Parameters:

prompt - user prompt

Returns:

a String containing the characters the user typed in up to (not including) a newline.

Throws:

java.io.IOException - i/o error when reading from console

readString

public static java.lang.String readString(java.lang.String prompt,
                                          java.lang.String defaultValue)

Displays the given prompt, and then waits for the user to type a line, and then returns all characters the user typed as a string.

Parameters:

prompt - user prompt

Returns:

a String containing the characters the user typed in up to (not including) a newline, or defaultValue if there was an I/O error

readLong

public static long readLong()
                     throws java.io.IOException

Waits for the user to type a number, and then returns that number as a long. If the user enters an invalid response, the program prompts the user to retype the response.

Returns:

the number typed in by the user as a long

Throws:

java.io.IOException - i/o error when reading from console

readLong

public static long readLong(long defaultValue)

Waits for the user to type a number, and then returns that number as a long. If the user enters an invalid response, the program prompts the user to retype the response.

Returns:

the number typed in by the user as a long, or defaultValue if there was an I/O error

readLong

public static long readLong(java.lang.String prompt)
                     throws java.io.IOException

Displays the given prompt, and then waits for the user to type a number, and then returns that number as a long. If the user enters an invalid response, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as a long

Throws:

java.io.IOException - i/o error when reading from console

readLong

public static long readLong(java.lang.String prompt,
                            long defaultValue)

Displays the given prompt, and then waits for the user to type a number, and then returns that number as a long. If the user enters an invalid response, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as a long, or defaultValue if there was an I/O error

readLong

public static long readLong(java.lang.String prompt,
                            int lowValue,
                            int highValue)
                     throws java.io.IOException

Displays the given prompt, and then waits for the user to type a number, and then returns that number as a long. If the user enters an invalid response, the program prompts the user to retype the response. If the user types a value outside the range from lowValue to highValue, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as a long

Throws:

java.io.IOException - i/o error when reading from console

Precondition:

highValue >= lowValue

readLong

public static long readLong(java.lang.String prompt,
                            int lowValue,
                            int highValue,
                            long defaultValue)

Displays the given prompt, and then waits for the user to type a number, and then returns that number as a long. If the user enters an invalid response, the program prompts the user to retype the response. If the user types a value outside the range from lowValue to highValue, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as a long, or defaultValue if there was an I/O error

Precondition:

highValue >= lowValue

readInt

public static int readInt()
                   throws java.io.IOException

Waits for the user to type a number, and then returns that number as an int. If the user enters an invalid response, the program prompts the user to retype the response.

Returns:

the number typed in by the user as an int

Throws:

java.io.IOException - i/o error when reading from console

readInt

public static int readInt(int defaultValue)

Waits for the user to type a number, and then returns that number as an int. If the user enters an invalid response, the program prompts the user to retype the response.

Returns:

the number typed in by the user as an int, or defaultValue if there was an I/O error

readInt

public static int readInt(java.lang.String prompt)
                   throws java.io.IOException

Displays the given prompt, and then waits for the user to type a number, and then returns that number as an int. If the user enters an invalid response, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as an int

Throws:

java.io.IOException - i/o error when reading from console

readInt

public static int readInt(java.lang.String prompt,
                          int defaultValue)

Displays the given prompt, and then waits for the user to type a number, and then returns that number as an int. If the user enters an invalid response, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as an int, or defaultValue if there was an I/O error

readInt

public static int readInt(java.lang.String prompt,
                          int lowValue,
                          int highValue)
                   throws java.io.IOException

Displays the given prompt, and then waits for the user to type a number, and then returns that number as an int. If the user enters an invalid response, the program prompts the user to retype the response. If the user types a value outside the range from lowValue to highValue, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as an int

Throws:

java.io.IOException - i/o error when reading from console

Precondition:

highValue >= lowValue

readInt

public static int readInt(java.lang.String prompt,
                          int lowValue,
                          int highValue,
                          int defaultValue)

Displays the given prompt, and then waits for the user to type a number, and then returns that number as an int. If the user enters an invalid response, the program prompts the user to retype the response. If the user types a value outside the range from lowValue to highValue, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as an int, or defaultValue if there was an I/O error

Precondition:

highValue >= lowValue

readShort

public static short readShort()
                       throws java.io.IOException

Waits for the user to type a number, and then returns that number as a short. If the user enters an invalid response, the program prompts the user to retype the response.

Returns:

the number typed in by the user as a short

Throws:

java.io.IOException - i/o error when reading from console

readShort

public static short readShort(short defaultValue)

Waits for the user to type a number, and then returns that number as a short. If the user enters an invalid response, the program prompts the user to retype the response.

Returns:

the number typed in by the user as a short, or defaultValue if there was an I/O error

readShort

public static short readShort(java.lang.String prompt)
                       throws java.io.IOException

Displays the given prompt, and then waits for the user to type a number, and then returns that number as a short. If the user enters an invalid response, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as a short

Throws:

java.io.IOException - i/o error when reading from console

readShort

public static short readShort(java.lang.String prompt,
                              short defaultValue)

Displays the given prompt, and then waits for the user to type a number, and then returns that number as a short. If the user enters an invalid response, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as a short, or defaultValue if there was an I/O error

readShort

public static short readShort(java.lang.String prompt,
                              int lowValue,
                              int highValue)
                       throws java.io.IOException

Displays the given prompt, and then waits for the user to type a number, and then returns that number as a short. If the user enters an invalid response, the program prompts the user to retype the response. If the user types a value outside the range from lowValue to highValue, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as a short

Throws:

java.io.IOException - i/o error when reading from console

Precondition:

highValue >= lowValue

readShort

public static short readShort(java.lang.String prompt,
                              int lowValue,
                              int highValue,
                              short defaultValue)

Displays the given prompt, and then waits for the user to type a number, and then returns that number as a short. If the user enters an invalid response, the program prompts the user to retype the response. If the user types a value outside the range from lowValue to highValue, the program prompts the user to retype the response.

Parameters:

prompt - user prompt

Returns:

the number typed in by the user as a short, or defaultValue if there was an I/O error

Precondition:

highValue >= lowValue