Java tutorial
//package com.java2s; //License from project: Apache License import java.util.regex.Matcher; import java.util.regex.Pattern; public class Main { public static boolean isNumber(String str) { if (isLong(str)) { return true; } Pattern pattern = Pattern.compile("(-)?(\\d*)\\.{0,1}(\\d*)"); Matcher isNum = pattern.matcher(str); return isNum.matches(); } public static boolean isLong(String str) { if ("0".equals(str.trim())) { return true; } Pattern pattern = Pattern.compile("^[^0]\\d*"); Matcher isNum = pattern.matcher(str); return isNum.matches(); } }