WordPattern.java

/**
 * 
 */
package com.maalaang.omtwitter.text;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * @author Sangwon Park
 * 
 */
public class WordPattern {
	private static String patternPrefix = "WP_";
	private static Pattern pNumberRome = Pattern.compile("(ix|iv|vi{0,3}|i{2,3})");
	private static Pattern pNumberArabic = Pattern.compile("[0-9]+(\\.[0-9]+)*");

	public static String normalize(String value) {
		value = value.toLowerCase();
		value = value.replaceAll("[#@]", "");
		return value;
	}

	public static String[] normalize(String[] values) {
		for (int i = 0; i < values.length; i++) {
			values[i] = normalize(values[i]);
		}
		return values;
	}

	public static boolean isPatternName(String word) {
		return word.startsWith(patternPrefix);
	}

	public static String replaceRomanToArabic(String word) {
		Matcher m = pNumberRome.matcher(word);
		String res = word;
		while (m.find()) {
			String rome = m.group();
			int num = decodeRoman(rome);
			res = res.replaceFirst(rome, String.valueOf(num));
		}
		return res;
	}

	private static int decodeRoman(char letter) {
		switch (letter) {
		case 'm':
			return 1000;
		case 'd':
			return 500;
		case 'c':
			return 100;
		case 'l':
			return 50;
		case 'x':
			return 10;
		case 'v':
			return 5;
		case 'i':
			return 1;
		default:
			return 0;
		}
	}

	private static int decodeRoman(String roman) {
		int result = 0;
		roman = roman.toLowerCase();
		for (int i = 0; i < roman.length() - 1; i++) {
			if (decodeRoman(roman.charAt(i)) < decodeRoman(roman.charAt(i + 1))) {
				result -= decodeRoman(roman.charAt(i));
			} else {
				result += decodeRoman(roman.charAt(i));
			}
		}
		result += decodeRoman(roman.charAt(roman.length() - 1));
		return result;
	}
}