java中的正则匹配

import java.util.regex.Pattern;
import java.util.regex.Matcher;
public class RegexTest{
  public static void main(String [] args){
    //指定字符串
    String line = "this is a test" ;
    //创建Pattern对象
    String r = "(\\\\D*)(\\\\d+)(.*)";
    Pattern p = Pattern.compile(r);
    //创建Matcher对象
    Matcher m = p.matcher(line);
    //
    if(m.find()){
      System.out.println("find value:"+m.group(0));
      System.out.println("find value:"+m.group(1));
      System.out.println("find value:"+m.group(2));
      System.out.println("find value:"+m.group(3));
    }else{
      System.out.println("no match");
    }
  }
}