第1个回答 推荐于2016-07-31
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Test {
public static void check(String ss) {
System.out.print(ss + " 合法性: ");
String regex = "^[a-zA-Z_]+[a-zA-Z0-9_]*";
Pattern p = Pattern.compile(regex);
Matcher m = p.matcher(ss);
System.out.println(m.matches());
}
public static void main(String[] args) {
check("sk_jfl");
}
}本回答被提问者采纳