001// Generated by delombok at Mon Oct 02 22:30:47 BST 2023 002/* 003 * Licensed to the Apache Software Foundation (ASF) under one 004 * or more contributor license agreements. See the NOTICE file 005 * distributed with this work for additional information 006 * regarding copyright ownership. The ASF licenses this file 007 * to you under the Apache License, Version 2.0 (the 008 * "License"); you may not use this file except in compliance 009 * with the License. You may obtain a copy of the License at 010 * 011 * http://www.apache.org/licenses/LICENSE-2.0 012 * 013 * Unless required by applicable law or agreed to in writing, 014 * software distributed under the License is distributed on an 015 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 016 * KIND, either express or implied. See the License for the 017 * specific language governing permissions and limitations 018 * under the License. 019 */ 020package org.apache.causeway.extensions.pdfjs.wkt.ui.components; 021 022import org.apache.causeway.viewer.wicket.ui.util.LicensedTextTemplate; 023 024public class PdfJsViewerCallbacksReference extends LicensedTextTemplate { 025 private static final long serialVersionUID = 1L; 026 private static final java.util.concurrent.atomic.AtomicReference<java.lang.Object> instance = new java.util.concurrent.atomic.AtomicReference<java.lang.Object>(); 027 028 private PdfJsViewerCallbacksReference() { 029 // skip 18 leading lines in referenced java-script 030 super(PdfJsViewerCallbacksReference.class, "PdfJsViewerPanelCallbacks.template.js", 18); 031 } 032 033 @java.lang.SuppressWarnings({"all", "unchecked"}) 034 public static PdfJsViewerCallbacksReference instance() { 035 java.lang.Object value = PdfJsViewerCallbacksReference.instance.get(); 036 if (value == null) { 037 synchronized (PdfJsViewerCallbacksReference.instance) { 038 value = PdfJsViewerCallbacksReference.instance.get(); 039 if (value == null) { 040 final PdfJsViewerCallbacksReference actualValue = new PdfJsViewerCallbacksReference(); 041 value = actualValue == null ? PdfJsViewerCallbacksReference.instance : actualValue; 042 PdfJsViewerCallbacksReference.instance.set(value); 043 } 044 } 045 } 046 return (PdfJsViewerCallbacksReference) (value == PdfJsViewerCallbacksReference.instance ? null : value); 047 } 048}