edu.northwestern.at.utils

Class RomanNumeralUtils

java.lang.Object

edu.northwestern.at.utils.RomanNumeralUtils

public class RomanNumeralUtils
extends java.lang.Object

Roman numeral utilities.

This static class provides various utility methods for working with Roman numerals. The range of values supported is 1 through 5000 .

Field Summary

Fields

Modifier and Type	Field and Description
protected static java.util.Map<java.lang.Integer,java.lang.String>	integerToRomanMap Integer to Roman numerals map for 1 - 5000 .
protected static int[]	integerValues Integer values for entries in "romanNumerals".
static java.lang.String	looseOrdinalRomanNumeralPattern Ordinal Roman numeral pattern.
protected static java.lang.String	looseRomanNumeralPattern Regular expression pattern matching a looser Roman numeral.
protected static int	MAX_ROMAN_NUMERAL Maximum Roman Numeral value handled here.
protected static java.lang.String	romanNumeralPattern Regular expression pattern matching a Roman numeral.
protected static java.lang.String[]	romanNumerals Roman numeral strings.
protected static java.util.Map<java.lang.String,java.lang.Integer>	romanToIntegerMap Roman numerals to integer map for 1 - 5000 .

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	RomanNumeralUtils() Don't allow instantiation, do allow overrides.

Method Summary

Methods

Modifier and Type	Method and Description
protected static java.lang.String	integerToRoman(int n) Convert integer to a Roman numeral.
static java.lang.String	integerToRomanNumerals(int i) Convert integer to a Roman numeral.
static boolean	isLooseOrdinalRomanNumeral(java.lang.String s) See if string is an ordinal Roman numeral using looser definition.
static boolean	isLooseRomanNumeral(java.lang.String s) See if string is a Roman numeral using looser (older) definition.
static boolean	isRomanNumeral(java.lang.String s) See if string is a Roman numeral.
static int	romanNumeralsToInteger(java.lang.String s) Convert Roman numeral to integer.

Methods inherited from class java.lang.Object

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

Field Detail

MAX_ROMAN_NUMERAL

protected static final int MAX_ROMAN_NUMERAL

Maximum Roman Numeral value handled here.

See Also:

Constant Field Values

romanNumeralPattern

protected static java.lang.String romanNumeralPattern

Regular expression pattern matching a Roman numeral.

looseRomanNumeralPattern

protected static java.lang.String looseRomanNumeralPattern

Regular expression pattern matching a looser Roman numeral.

looseOrdinalRomanNumeralPattern

public static java.lang.String looseOrdinalRomanNumeralPattern

Ordinal Roman numeral pattern.

integerToRomanMap

protected static java.util.Map<java.lang.Integer,java.lang.String> integerToRomanMap

Integer to Roman numerals map for 1 - 5000 .

romanToIntegerMap

protected static java.util.Map<java.lang.String,java.lang.Integer> romanToIntegerMap

Roman numerals to integer map for 1 - 5000 .

romanNumerals

protected static java.lang.String[] romanNumerals

Roman numeral strings.

integerValues

protected static int[] integerValues

Integer values for entries in "romanNumerals".

Constructor Detail

RomanNumeralUtils

protected RomanNumeralUtils()

Don't allow instantiation, do allow overrides.

Method Detail

isRomanNumeral

public static boolean isRomanNumeral(java.lang.String s)

See if string is a Roman numeral.

Parameters:

s - The string.

Returns:

true if string is a valid Roman numeral.

isLooseRomanNumeral

public static boolean isLooseRomanNumeral(java.lang.String s)

See if string is a Roman numeral using looser (older) definition.

Parameters:

s - The string.

Returns:

true if string is a valid Roman numeral using looser (older) definition.

isLooseOrdinalRomanNumeral

public static boolean isLooseOrdinalRomanNumeral(java.lang.String s)

See if string is an ordinal Roman numeral using looser definition.

Parameters:

s - The string.

Returns:

true if string is a valid Roman ordinal numeral using looser (older) definition.

romanNumeralsToInteger

public static int romanNumeralsToInteger(java.lang.String s)

Convert Roman numeral to integer.

Parameters:

s - The Roman numeral as a string.

Returns:

The corresponding decimal integer. -1 if Roman numeral string is bad.

integerToRomanNumerals

public static java.lang.String integerToRomanNumerals(int i)

Convert integer to a Roman numeral.

Parameters:

i - The integer to convert to a Roman numeral. Must be 1 < i <= 5000 .

Returns:

The corresponding Roman numeral as a string. "" if input value is invalid.

integerToRoman

protected static java.lang.String integerToRoman(int n)

Convert integer to a Roman numeral.

Parameters:

n - The integer to convert to a Roman numeral.

Returns:

The corresponding Roman numeral as a string.