Java tutorial
/* * Copyright (c) 2011-2015 Marat Gubaidullin. * * This file is part of HYBRIDBPM. * * 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.hybridbpm.ui.component.document; import com.hybridbpm.core.data.document.Document; import com.hybridbpm.ui.HybridbpmUI; import com.hybridbpm.ui.util.Translate; import com.vaadin.server.FileDownloader; import com.vaadin.server.StreamResource; import com.vaadin.server.VaadinRequest; import com.vaadin.server.VaadinResponse; import com.vaadin.ui.Button; import com.vaadin.ui.Button.ClickListener; import com.vaadin.ui.Table; import com.vaadin.ui.themes.ValoTheme; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.util.Locale; import java.util.Objects; /** * * @author Marat Gubaidullin */ public final class DocumentColumnGenerator implements Table.ColumnGenerator { private final ClickListener clickListener; public DocumentColumnGenerator(ClickListener clickListener) { this.clickListener = clickListener; } @Override public Object generateCell(Table source, Object itemId, Object columnId) { Document document = (Document) itemId; Button button = new Button(document.getName()); button.setData(document); button.addStyleName(ValoTheme.BUTTON_LINK); if (Objects.equals(document.getType(), Document.TYPE.FILE)) { OnDemandFileDownloader onDemandFileDownloader = new OnDemandFileDownloader(document.getId().toString(), document.getName()); onDemandFileDownloader.extend(button); button.setDescription(Translate.getMessage("btnDownload")); } else { button.setDescription(Translate.getMessage("btnOpen")); button.addClickListener(clickListener); } return button; } class OnDemandStreamResource extends StreamResource { public OnDemandStreamResource() { super(() -> new ByteArrayInputStream(new byte[1]), ""); } } class OnDemandFileDownloader extends FileDownloader { private final String documentId; private final String name; public OnDemandFileDownloader(String documentId, String name) { super(new OnDemandStreamResource()); this.documentId = documentId; this.name = name; } @Override public boolean handleConnectorRequest(VaadinRequest request, VaadinResponse response, String path) throws IOException { StreamResource resource = new StreamResource(() -> { Document doc = HybridbpmUI.getDocumentAPI().getDocumentById(documentId, true); return new ByteArrayInputStream(doc.getBody()); }, name); this.setResource("dl", resource); return super.handleConnectorRequest(request, response, path); } } }