Java tutorial
//package com.java2s; /* * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import java.util.regex.Matcher; import java.util.regex.Pattern; public class Main { public static boolean isNumeric(String str) { Pattern pattern = Pattern.compile("^\\d+$"); Matcher isNum = pattern.matcher(str); if (!isNum.matches()) { return false; } return true; } }