获取指定字符第几次出现的下标
public static int getIndexOf(String data, String str,int num) {
Pattern pattern = Pattern.compile(str);
Matcher findMatcher = pattern.matcher(data);
//标记遍历字符串的位置
int indexNum = 0;
while (findMatcher.find()) {
indexNum++;
if (indexNum == num) {
break;
}
}
return findMatcher.start();
}