Java tutorial
/* * Copyright (c) 2008-2017 Haulmont. * * 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 com.haulmont.cuba.web.widgets; import com.vaadin.server.AbstractExtension; import com.vaadin.server.Extension; import com.vaadin.ui.UI; @WebJarResource("object-fit-images:ofi.min.js") public class CubaImageObjectFitPolyfillExtension extends AbstractExtension { public void extend(CubaImage image) { super.extend(image); } public static CubaImageObjectFitPolyfillExtension get(UI ui) { CubaImageObjectFitPolyfillExtension extension = null; // Search singleton extension for (Extension uiExtension : ui.getExtensions()) { if (uiExtension instanceof CubaImageObjectFitPolyfillExtension) { extension = (CubaImageObjectFitPolyfillExtension) uiExtension; break; } } // Create new extension if not found if (extension == null) { extension = new CubaImageObjectFitPolyfillExtension(); extension.extend(ui); } return extension; } }