前言：我当时是将文件名得到后，想将文件名字换成pinyin

需要引入的依赖

  <dependency>
            <groupId>com.belerweb</groupId>
            <artifactId>pinyin4j</artifactId>
            <version>2.5.0</version>
  </dependency>

具体代码如下：

/**
 * 汉字转换为拼音
 * @author Red
 */
public class Demo {
    /**
     * 测试main方法
     * @param args
     */
    public static void main(String[] args) {
        System.out.println(ToFirstChar("汉字转换为拼音").toLowerCase()); //转为首字母大写
        System.out.println(ToPinyin("汉字转换为拼音"));
        int max=100,min=1;
        int ran2 = (int) (Math.random()*(max-min)+min);
        System.out.println(ran2);
    }
    /**
     * 获取字符串拼音的第一个字母
     * @param chinese
     * @return
     */
    public static String ToFirstChar(String chinese){
        String pinyinStr = "";
        char[] newChar = chinese.toCharArray();  //转为单个字符
        HanyuPinyinOutputFormat defaultFormat = new HanyuPinyinOutputFormat();
        defaultFormat.setCaseType(HanyuPinyinCaseType.LOWERCASE);
        defaultFormat.setToneType(HanyuPinyinToneType.WITHOUT_TONE);
        for (int i = 0; i < newChar.length; i++) {
            if (newChar[i] > 128) {
                try {
                    pinyinStr += PinyinHelper.toHanyuPinyinStringArray(newChar[i], defaultFormat)[0].charAt(0);
                } catch (BadHanyuPinyinOutputFormatCombination e) {
                    e.printStackTrace();
                }
            }else{
                pinyinStr += newChar[i];
            }
        }
        return pinyinStr;
    }

    /**
     * 汉字转为拼音
     * @param chinese
     * @return
     */
    public static String ToPinyin(String chinese){
        String pinyinStr = "";
        char[] newChar = chinese.toCharArray();
        HanyuPinyinOutputFormat defaultFormat = new HanyuPinyinOutputFormat();
        defaultFormat.setCaseType(HanyuPinyinCaseType.LOWERCASE);
        defaultFormat.setToneType(HanyuPinyinToneType.WITHOUT_TONE);
        for (int i = 0; i < newChar.length; i++) {
            if (newChar[i] > 128) {
                try {
                    pinyinStr += PinyinHelper.toHanyuPinyinStringArray(newChar[i], defaultFormat)[0];
                } catch (BadHanyuPinyinOutputFormatCombination e) {
                    e.printStackTrace();
                }
            }else{
                pinyinStr += newChar[i];
            }
        }
        return pinyinStr;
    }
}