learning java 正则表达式

        var regStr = "Java is very good";
        Matcher m  = Pattern.compile("\\w+").matcher(regStr);
        while(m.find()){
            System.out.println(m.group() + " start:" + m.start() + ",end:" + m.end());
        }

output:

Java start:,end:
is start:,end:
very start:,end:
good start:,end: