Java tutorial
/******************************************************************************* * Copyright 2015 DANS - Data Archiving and Networked Services * * 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. *******************************************************************************/ package nl.knaw.dans.common.wicket.util; import org.apache.wicket.validation.validator.PatternValidator; public class TelephoneNumberValidator extends PatternValidator { public static final String PATTERN_TELEPHONE = "[+]?((\\([0-9- ]+\\))|[0-9- ]+)+"; private static final long serialVersionUID = 8803635130499334848L; private static TelephoneNumberValidator instance; public static TelephoneNumberValidator instance() { if (instance == null) { instance = new TelephoneNumberValidator(); } return instance; } private TelephoneNumberValidator() { super(PATTERN_TELEPHONE); } }