将阿拉伯数字转换成汉语言金额大写

将阿拉伯数字转换成中文金额大写
前段时间在javaeye上看到一篇关于将数字转换成中文金额大写文章：将数字转换成中文金额大写形式（Java版），写得很不错，我也来写一个，我觉得这个算法比其更简单有效。闲话少说，大家看代码吧，代码很简单。

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

public class CurrencyConverter {

	private static final double MAXIMUM_NUMBER = 9999999999999.99d;

	private static final String CN_ZERO = "零";
	private static final String CN_SYMBOL = "￥:";
	private static final String CN_DOLLAR = "圆";
	private static final String CN_INTEGER = "整";

	private static final String[] digits = new String[] { "零", "壹", "贰", "叁", "肆", "伍", "陆", "柒", "捌", "玖" };
	private static final String[] radices = new String[] { "", "拾", "佰", "仟" };
	private static final String[] bigRadices = new String[] { "", "万", "亿", "万" };
	private static final String[] decimals = new String[] { "角", "分" };

	public static void main(String[] args) {

		// 键盘输入数字
		String currencyDigits = input();
		// 检查数字合法性
		if (check(currencyDigits)) {
			//转换大写并输出
			System.out.println(convert(currencyDigits));
		}
	}

	/**
	 * 转换大写
	 * 
	 * @param currencyDigits
	 * @return
	 */
	public static String convert(String currencyDigits) {

		String integral = null; // 整数部分
		String decimal = null; // 小数部分
		String outputCharacters = null; // 最终转换输出结果

		String d = null;
		int zeroCount = 0, p = 0, quotient = 0, modulus = 0;

		// 删除数字中的逗号,
		currencyDigits = currencyDigits.replace("/,/g", "");
		// 删除数字左边的0
		currencyDigits = currencyDigits.replace("/^0+/", "");

		// 拆分数字中的整数与小数部分
		String[] parts = currencyDigits.split("\\.");
		if (parts.length > 1) {
			integral = parts[0];
			decimal = parts[1];

			// 如果小数部分长度大于2，四舍五入，保留两位小数
			if (decimal.length() > 2) {
				long dd = Math.round(Double.parseDouble("0."+decimal) * 100) ;
				decimal = Long.toString(dd);
			}

		} else {
			integral = parts[0];
			decimal = "0";
		}

		// Start processing:
		outputCharacters = "";
		// Process integral part if it is larger than 0:
		if (Double.parseDouble(integral) > 0) {

			zeroCount = 0;

			for (int i = 0; i < integral.length(); i++) {

				p = integral.length() - i - 1;
				d = integral.substring(i, i + 1);

				quotient = p / 4;
				modulus = p % 4;
				if (d.equals("0")) {
					zeroCount++;
				} else {
					if (zeroCount > 0) {
						outputCharacters += digits[0];
					}
					zeroCount = 0;
					outputCharacters += digits[Integer.parseInt(d)] + radices[modulus];
				}
				if (modulus == 0 && zeroCount < 4) {
					outputCharacters += bigRadices[quotient];
				}
			}
			outputCharacters += CN_DOLLAR;
		}

		// Process decimal part if it is larger than 0:
		if (Double.parseDouble(decimal) > 0) {
			for (int i = 0; i < decimal.length(); i++) {
				d = decimal.substring(i, i + 1);
				if (!d.equals("0")) {
					outputCharacters += digits[Integer.parseInt(d)] + decimals[i];
				} else {
					if (i == 0) {
						outputCharacters += CN_ZERO;
					}
				}
			}
		}
		
		// Confirm and return the final output string:
		if (outputCharacters.equals("")) {
			outputCharacters = CN_ZERO + CN_DOLLAR;
		}
		if (decimal == null || decimal.equals("0")) {
			outputCharacters += CN_INTEGER;
		}

		outputCharacters = CN_SYMBOL + outputCharacters;
		return outputCharacters;
	}

	/**
	 * 从键盘输入要转换的数字
	 * 
	 * @return
	 */
	private static String input() {

		System.out.println("请输入一个数字（精确到小数点后两位）：");
		Scanner scanner = new Scanner(System.in);
		String currencyDigits = scanner.next();
		scanner.close();
		return currencyDigits;
	}

	/**
	 * 检查输入数字的合法性
	 * 
	 * @param currencyDigits
	 * @return
	 */
	private static boolean check(final String currencyDigits) {
		if (currencyDigits == null || currencyDigits.trim().equals("")) {
			System.out.println("没有输入要转换的数字");
			return false;
		}

		Pattern pattern = Pattern.compile("/[^,.\\d]/", Pattern.CASE_INSENSITIVE);
		Matcher matcher = pattern.matcher(currencyDigits);

		if (matcher.find()) {
			System.out.println("数字中含有非法字符!");
			return false;
		}

		pattern = Pattern.compile("/^((\\d{1,3}(,\\d{3})*(.((\\d{3},)*\\d{1,3}))?)|(\\d+(.\\d+)?))$/",
				Pattern.CASE_INSENSITIVE);
		matcher = pattern.matcher(currencyDigits);
		if (matcher.find()) {
			System.out.println("错误的数字格式!");
			return false;
		}

		if (Double.parseDouble(currencyDigits) > MAXIMUM_NUMBER) {
			System.out.println("超出转换最大范围!");
			return false;
		}

		return true;
	}
}