java 将数字替换成下划线

 1 import java.util.regex.Matcher;
 2 import java.util.regex.Pattern;
 3 public class RegexDemo {
 4     public static void main(String[] args) {
 5         String str="A1B22C333D4444E55555";
 6         String pat="\\d+";
 7         Pattern p=Pattern.compile(pat);
 8         Matcher m=p.matcher(str);
 9         String newS=m.replaceAll("_");
10         System.out.print(newS);
11     }
12 }