java有关正则表达式的工具方法集合1

Posted 2020-12-09 lgqrlchinese

1.获取某字符串中汉字的个数

 1 ...
 2     private int getChineseCount(String text) {
 3         String Reg = "^[u4e00-u9fa5]{1}$";// 正则
 4         int result = 0;
 5         for (int i = 0; i < text.length(); i++) {
 6             String b = Character.toString(text.charAt(i));
 7             if (b.matches(Reg))
 8                 result++;
 9         }
10         return result;
11     }
12 ...

 2.使用正则替换某字符串中所有符合正则的字符串为指定字符串

1 //将str中的符合正则regu的字符串替换成replaceStr
2 ...
3     private static String replace(String str, String regu, String replaceStr) {
4         Pattern pattern = Pattern.compile(regu);
5         Matcher matcher = pattern.matcher(str);
6         str = matcher.replaceAll(replaceStr);
7         return str;
8     }
9 ...

 3.驼峰式转换成大写下划线

 1 ...
 2     private String humpToLine(String str) {
 3         Pattern humpPattern = Pattern.compile("[A-Z]");
 4         Matcher matcher = humpPattern.matcher(str);
 5         StringBuffer sb = new StringBuffer();
 6         while (matcher.find()) {
 7             matcher.appendReplacement(sb, "_" + matcher.group(0).toLowerCase());
 8         }
 9         matcher.appendTail(sb);
10         return sb.toString().toUpperCase();
11     }
12 ...

 4.大写下划线转换成驼峰式

 1 ...
 2     private String lineToHump(String str) {
 3         Pattern linePattern = Pattern.compile("_(\w)");
 4         str = str.toLowerCase();
 5         Matcher matcher = linePattern.matcher(str);
 6         StringBuffer sb = new StringBuffer();
 7         while (matcher.find()) {
 8             matcher.appendReplacement(sb, matcher.group(1).toUpperCase());
 9         }
10         matcher.appendTail(sb);
11         return sb.toString();
12     }
13 ...