判断字符窜不是数字

import java.util.regex.Matcher;import java.util.regex.Pattern;public class isNumeric {public boolean isNumeric(String str) {Pattern pattern = Pattern.compile("[0-9]*");Matcher isNum = pattern.matcher(str);if (!isNum.matches()) {return false;}return true;}public static void main(String[] args) {//int a = 10;isNumeric m = new isNumeric();System.out.println(m.isNumeric("1213ss23"));}}