LetterUtil.java

package my.project.easyrecharge.util;

import java.io.UnsupportedEncodingException;

public class LetterUtil {

	private final static int[] li_SecPosValue = { 1601, 1637, 1833, 2078, 2274,
			2302, 2433, 2594, 2787, 3106, 3212, 3472, 3635, 3722, 3730, 3858,
			4027, 4086, 4390, 4558, 4684, 4925, 5249, 5590 };

	private final static String[] lc_FirstLetter = { "a", "b", "c", "d", "e",
			"f", "g", "h", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s",
			"t", "w", "x", "y", "z" };

	public static String getFirstLetter(String chinese) {
		if (chinese == null || chinese.trim().length() == 0) {
			return "";
		}
		chinese = conversionStr(chinese, "GBK", "ISO8859-1");
		if (chinese.length() > 1) {
			int li_SectorCode = (int) chinese.charAt(0);
			int li_PositionCode = (int) chinese.charAt(1);
			li_SectorCode = li_SectorCode - 160;
			li_PositionCode = li_PositionCode - 160;
			int li_SecPosCode = li_SectorCode * 100 + li_PositionCode;
			if (li_SecPosCode > 1600 && li_SecPosCode < 5590) {
				for (int i = 0; i < 23; i++) {
					if (li_SecPosCode >= li_SecPosValue[i]
							&& li_SecPosCode < li_SecPosValue[i + 1]) {
						chinese = lc_FirstLetter[i];
						break;
					}
				}
			}
		}
		return chinese;
	}

	private static String conversionStr(String str, String charsetName,
			String toCharsetName) {
		try {
			str = new String(str.getBytes(charsetName), toCharsetName);
		} catch (UnsupportedEncodingException ex) {
			System.out.println("字符串编码转换异常：" + ex.getMessage());
		}

		return str;
	}

}