Java tutorial
/* * JasperReports - Free Java Reporting Library. * Copyright (C) 2001 - 2019 TIBCO Software Inc. All rights reserved. * http://www.jaspersoft.com * * Unless you have purchased a commercial license agreement from Jaspersoft, * the following license terms apply: * * This program is part of JasperReports. * * JasperReports is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * JasperReports is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with JasperReports. If not, see <http://www.gnu.org/licenses/>. */ package net.sf.jasperreports.web.servlets; import java.io.IOException; import java.io.PrintWriter; import java.util.HashMap; import java.util.Map; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import net.sf.jasperreports.engine.JRConstants; import net.sf.jasperreports.engine.JRPropertiesUtil; import net.sf.jasperreports.web.WebReportContext; import net.sf.jasperreports.web.util.VelocityUtil; import net.sf.jasperreports.web.util.WebUtil; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * @author Teodor Danciu (teodord@users.sourceforge.net) */ public class ViewerServlet extends AbstractServlet { private static final long serialVersionUID = JRConstants.SERIAL_VERSION_UID; private static final Log log = LogFactory.getLog(ViewerServlet.class); public static final String PROPERTY_TEMPLATE_HEADER = "net.sf.jasperreports.web.servlets.viewer.header.template"; public static final String PROPERTY_TEMPLATE_BODY = "net.sf.jasperreports.web.servlets.viewer.body.template"; public static final String PROPERTY_TEMPLATE_FOOTER = "net.sf.jasperreports.web.servlets.viewer.footer.template"; private String headerTemplate; private String bodyTemplate; private String footerTemplate; @Override public void init() throws ServletException { super.init(); headerTemplate = getInitParameter(PROPERTY_TEMPLATE_HEADER); bodyTemplate = getInitParameter(PROPERTY_TEMPLATE_BODY); footerTemplate = getInitParameter(PROPERTY_TEMPLATE_FOOTER); } /** * */ public String getHeaderTemplate() { if (headerTemplate == null) { return JRPropertiesUtil.getInstance(getJasperReportsContext()).getProperty(PROPERTY_TEMPLATE_HEADER); } return headerTemplate; } /** * */ public String getBodyTemplate() { if (bodyTemplate == null) { return JRPropertiesUtil.getInstance(getJasperReportsContext()).getProperty(PROPERTY_TEMPLATE_BODY); } return bodyTemplate; } /** * */ public String getFooterTemplate() { if (footerTemplate == null) { return JRPropertiesUtil.getInstance(getJasperReportsContext()).getProperty(PROPERTY_TEMPLATE_FOOTER); } return footerTemplate; } @Override public void service(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { response.setContentType("text/html; charset=UTF-8"); // Set to expire far in the past. response.setHeader("Expires", "Sat, 6 May 1995 12:00:00 GMT"); // Set standard HTTP/1.1 no-cache headers. response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate"); // Set IE extended HTTP/1.1 no-cache headers (use addHeader). response.addHeader("Cache-Control", "post-check=0, pre-check=0"); // Set standard HTTP/1.0 no-cache header. response.setHeader("Pragma", "no-cache"); PrintWriter out = response.getWriter(); WebReportContext webReportContext = WebReportContext.getInstance(request); try { render(request, webReportContext, out); } catch (Exception e) { log.error("Error on report execution", e); out.println("<html>");//FIXMEJIVE do we need to render this? or should this be done by the viewer? out.println("<head>"); out.println("<title>JasperReports - Web Application Sample</title>"); out.println("<link rel=\"stylesheet\" type=\"text/css\" href=\"../stylesheet.css\" title=\"Style\">"); out.println("</head>"); out.println("<body bgcolor=\"white\">"); out.println("<span class=\"bnew\">JasperReports encountered this error :</span>"); out.println("<pre>"); e.printStackTrace(out); out.println("</pre>"); out.println("</body>"); out.println("</html>"); } } /** * */ public void render(HttpServletRequest request, WebReportContext webReportContext, PrintWriter writer) { writer.write(getHeader(request, webReportContext)); writer.write(getBody(request, webReportContext)); writer.write(getFooter()); } protected String getHeader(HttpServletRequest request, WebReportContext webReportContext) { Map<String, Object> contextMap = new HashMap<String, Object>(); WebUtil webUtil = WebUtil.getInstance(getJasperReportsContext()); String webResourcesBasePath = webUtil.getResourcesBasePath(); contextMap.put("contextPath", request.getContextPath()); contextMap.put("resourcesPath", request.getContextPath() + webResourcesBasePath); contextMap.put("jasperreports_global_css", request.getContextPath() + webUtil.getResourcePath(webResourcesBasePath, WebUtil.RESOURCE_JR_GLOBAL_CSS)); return VelocityUtil.processTemplate(getHeaderTemplate(), contextMap); } protected String getBody(HttpServletRequest request, WebReportContext webReportContext) { Map<String, Object> contextMap = new HashMap<String, Object>(); String reportUri = request.getParameter(WebUtil.REQUEST_PARAMETER_REPORT_URI); contextMap.put("reportUri", reportUri); contextMap.put("async", Boolean.valueOf(request.getParameter(WebUtil.REQUEST_PARAMETER_ASYNC_REPORT))); String reportPage = request.getParameter(WebUtil.REQUEST_PARAMETER_PAGE); int pageIdx = reportPage == null ? 0 : Integer.parseInt(reportPage); contextMap.put("page", pageIdx); contextMap.put("contextPath", request.getContextPath()); return VelocityUtil.processTemplate(getBodyTemplate(), contextMap); } protected String getFooter() { return VelocityUtil.processTemplate(getFooterTemplate(), new HashMap<String, Object>()); } }