com.github.fracpete.romannumerals4j

Class RomanNumeralFormat

java.lang.Object

java.text.Format

java.text.NumberFormat

com.github.fracpete.romannumerals4j.RomanNumeralFormat

All Implemented Interfaces:

Serializable, Cloneable

public class RomanNumeralFormat
extends NumberFormat

Simple format/parse class for Roman Numerals, sourced from several StackOverflow posts. Roman numerals only cover 1 to 3999.

Version:

$Revision$

Author:

FracPete (fracpete at waikato dot ac dot nz), paxdiablo (regexp - http://stackoverflow.com/a/267405), Ravindra Gullapalli (roman to int - http://stackoverflow.com/a/9073310), chepe lucho (int to roman - http://stackoverflow.com/a/17376764)

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.text.NumberFormat

NumberFormat.Field

Field Summary

Fields

Modifier and Type	Field and Description
static String	CHECK_REGEXP expression for checking roman numeral.
protected static LinkedHashMap<String,Integer>	m_RomanNumerals the hashmap for the numerals.

Fields inherited from class java.text.NumberFormat

FRACTION_FIELD, INTEGER_FIELD

Constructor Summary

Constructors

Constructor and Description
RomanNumeralFormat()

Method Summary

Modifier and Type	Method and Description
StringBuffer	format(double number, StringBuffer toAppendTo, FieldPosition pos) Specialization of format.
StringBuffer	format(long number, StringBuffer toAppendTo, FieldPosition pos) Specialization of format.
boolean	isGroupingUsed() Returns whether grouping is used.
boolean	isParseIntegerOnly() Returns whether numbers are parsed as integers.
Number	parse(String source, ParsePosition parsePosition) Returns a Long if possible (e.g., within the range [Long.MIN_VALUE, Long.MAX_VALUE] and with no decimals), otherwise a Double.
protected int	processDecimal(int decimal, int lastNumber, int lastDecimal) Adds/subtracts the decimal from the lastDecimal based on lastNumber.
protected String	repeatFormat(String s, int n) Repeats the format string a number of times.

Methods inherited from class java.text.NumberFormat

clone, equals, format, format, format, getAvailableLocales, getCurrency, getCurrencyInstance, getCurrencyInstance, getInstance, getInstance, getIntegerInstance, getIntegerInstance, getMaximumFractionDigits, getMaximumIntegerDigits, getMinimumFractionDigits, getMinimumIntegerDigits, getNumberInstance, getNumberInstance, getPercentInstance, getPercentInstance, getRoundingMode, hashCode, parse, parseObject, setCurrency, setGroupingUsed, setMaximumFractionDigits, setMaximumIntegerDigits, setMinimumFractionDigits, setMinimumIntegerDigits, setParseIntegerOnly, setRoundingMode

Methods inherited from class java.text.Format

format, formatToCharacterIterator, parseObject

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Field Detail

CHECK_REGEXP

public static final String CHECK_REGEXP

expression for checking roman numeral.

See Also:

Constant Field Values

m_RomanNumerals

protected static LinkedHashMap<String,Integer> m_RomanNumerals

the hashmap for the numerals.

Constructor Detail

RomanNumeralFormat

public RomanNumeralFormat()

Method Detail

isGroupingUsed

public boolean isGroupingUsed()

Returns whether grouping is used.

Overrides:

isGroupingUsed in class NumberFormat

Returns:

always false

isParseIntegerOnly

public boolean isParseIntegerOnly()

Returns whether numbers are parsed as integers.

Overrides:

isParseIntegerOnly in class NumberFormat

Returns:

always true

format

public StringBuffer format(double number,
                           StringBuffer toAppendTo,
                           FieldPosition pos)

Specialization of format.

Specified by:

format in class NumberFormat

Parameters:

number - the double number to format

toAppendTo - the StringBuffer to which the formatted text is to be appended

pos - the field position

Returns:

the formatted StringBuffer

Throws:

ArithmeticException - if rounding is needed with rounding mode being set to RoundingMode.UNNECESSARY

See Also:

Format.format(java.lang.Object)

repeatFormat

protected String repeatFormat(String s,
                              int n)

Repeats the format string a number of times.

Parameters:

s - the format to repeat

n - the number of times to repeat

Returns:

the generated string

format

public StringBuffer format(long number,
                           StringBuffer toAppendTo,
                           FieldPosition pos)

Specialization of format.

Specified by:

format in class NumberFormat

Parameters:

number - the long number to format

toAppendTo - the StringBuffer to which the formatted text is to be appended

pos - the field position

Returns:

the formatted StringBuffer

Throws:

ArithmeticException - if rounding is needed with rounding mode being set to RoundingMode.UNNECESSARY

See Also:

Format.format(java.lang.Object)

processDecimal

protected int processDecimal(int decimal,
                             int lastNumber,
                             int lastDecimal)

Adds/subtracts the decimal from the lastDecimal based on lastNumber.

Parameters:

decimal - the decimal to add/subtract

lastNumber - the last number encountered

lastDecimal - the tally so far

Returns:

the updated value

parse

public Number parse(String source,
                    ParsePosition parsePosition)

Returns a Long if possible (e.g., within the range [Long.MIN_VALUE, Long.MAX_VALUE] and with no decimals), otherwise a Double. If IntegerOnly is set, will stop at a decimal point (or equivalent; e.g., for rational numbers "1 2/3", will stop after the 1). Does not throw an exception; if no object can be parsed, index is unchanged!

Specified by:

parse in class NumberFormat

Parameters:

source - the String to parse

parsePosition - the parse position

Returns:

the parsed value

See Also:

NumberFormat.isParseIntegerOnly(), Format.parseObject(java.lang.String, java.text.ParsePosition)