/* * JasperReports - Free Java Reporting Library. * Copyright (C) 2001 - 2013 Jaspersoft Corporation. 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 . */ /** * Contains the Jasper viewer implementation. *
*

Viewing Reports

* The JasperReports library comes with built-in viewers for viewing the generated reports in its * proprietary format or in the proprietary XML format produced by the internal XML * exporter. It is a Swing-based component. Other Java applications can easily integrate this * component without having to export the documents into more popular formats in order to * be viewed or printed. The {@link net.sf.jasperreports.view.JRViewer} class represents * this visual component. It can be customized to respond to a particular application's needs * by subclassing it. For example, you could add or remove buttons from the existing * toolbar. *

* JasperReports also comes with a simple Swing application that uses the visual * component for viewing the reports. This application helps view reports stored on disk in * the JasperReports *.jrprint proprietary format or in the JRPXML format produced by * the default XML exporter. *

* This simple Java Swing application is implemented in the * {@link net.sf.jasperreports.view.JasperViewer} class and is used in almost all the * provided samples for viewing the generated reports. *

* To view a sample report if you have the Ant build tool installed on your system, go to the * desired sample directory and launch the following from the command line:

* 
 * >ant view
 * or
 * >ant viewXml
*

Customizing Viewers

* Built-in viewers are represented by the following two classes: * * However, these default viewers might not suit everybody's needs. You may want to * customize them to adapt to certain application requirements. If you need to do this, be * aware that these viewers actually use other, more basic visual components that come * with the JasperReports library. *

* The report viewers mentioned previously use the visual component represented by the * {@link net.sf.jasperreports.view.JRViewer} class and its companions. It is in fact a * special javax.swing.JPanel component that is capable of displaying generated * reports. It can be easily incorporated into other Java Swing-based applications or * applets. *

* If the functionality of this basic visual component is not sufficient, one can * adapt it by subclassing it. For example, to create an extra button on the toolbar of this * viewer, extend the component and add that button in the new visual component * obtained by subclassing. *

* Another very important issue is that the default report viewer that comes with the library * does not know how to deal with document hyperlinks that point to external resources. It * deals only with local references by redirecting the viewer to the corresponding local * anchor. *

* However, JasperReports lets users handle the clicks made on document hyperlinks that * point to external documents. To do this, simply implement the * {@link net.sf.jasperreports.view.JRHyperlinkListener} interface and add an instance * of this listener class to register with the viewer component, using the * addHyperlinkListener() method exposed by the * {@link net.sf.jasperreports.view.JRViewer} class. By doing this, you ensure that the * viewer will also call the implementation of the gotoHyperlink() method in which * the external references are handled. *

* There are two ways of rendering the current document page on the viewer component: *

* The first approach has the advantage of smoother scroll operations, since the page * content is rendered only once as an image, after which the scroll operations occur within * the view port of that image. The drawback is that at high zoom ratios, the image could * become so large that an out-of-memory error might occur. *

* The second approach avoids any potential memory problems at high zoom ratios by * rendering page content directly onto the view component, but this results in a drop of * performance that can be seen when scrolling the page. *

* Switching between the two rendering methods can be controlled by setting the * net.sf.jasperreports.viewer.render.buffer.max.size configuration property. * The value of this property represents the maximum size (in pixels) of a buffered image * that would be used by the {@link net.sf.jasperreports.view.JRViewer} component to render * a report page (the first rendering technique). If rendering a report page requires an * image larger than this threshold (that is, image width x image height > maximum size), * then the report page will be rendered directly on the viewer component. *

* By default, this configuration property is set to 0, which means that only direct rendering * is performed, no matter what the zoom ratio. * *

Related Documentation

* JasperReports Tutorial * * @see net.sf.jasperreports.view.JRHyperlinkListener */ package net.sf.jasperreports.view;