java 字符串下划线转驼峰

以下是两种Java字符串下划线转驼峰的方法：

1.使用split()和substring()方法：

public static void main(String[] args) {
    String destStr = "part_vote_num";
    StringBuilder sb = new StringBuilder();
    String[] arr = destStr.split("_");
    sb.append(arr[0]);
    for (int i = 1; i < arr.length; i++) {
        String temp = arr[i].substring(0, 1).toUpperCase() + arr[i].substring(1, arr[i].length());
        sb.append(temp);
    }
    System.out.println(sb.toString());
}

2.使用正则表达式和Matcher类：

public static void main(String[] args) {
    String destStr = "part_vote_num";
    Pattern p = Pattern.compile("_[a-z]");
    Matcher m = p.matcher(destStr);
    StringBuffer sb = new StringBuffer();
    while (m.find()) {
        String firstChar = m.group().substring(1, 2);
        m.appendReplacement(sb, firstChar.toUpperCase());
    }
    m.appendTail(sb);
    System.out.println(sb.toString());
}