java如何取得拼音的首字母

package com.junfun.pms;

import net.sourceforge.pinyin4j.PinyinHelper;

public class PinyinUtils {

    public static String getFirstLetter(String input) {
        StringBuilder result = new StringBuilder();
        for (char c : input.toCharArray()) {
            String[] pinyinArray = PinyinHelper.toHanyuPinyinStringArray(c);
            if (pinyinArray != null && pinyinArray.length > 0) {
                result.append(pinyinArray[0].charAt(0));
            } else {
                result.append(c);
            }
        }
        return result.toString().toUpperCase();
    }

    public static void main(String[] args) {
        String input = "切记一定是拼音";
        String firstLetters = getFirstLetter(input);
        System.out.println("拼音首字母：" + firstLetters);
    }
}