net.sf.jasperreports.engine.xml.XmlValueHandlerUtils Maven / Gradle / Ivy
/*
* JasperReports - Free Java Reporting Library.
* Copyright (C) 2001 - 2014 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 .
*/
package net.sf.jasperreports.engine.xml;
import java.io.IOException;
import java.util.List;
import net.sf.jasperreports.engine.export.JRXmlExporter;
import net.sf.jasperreports.extensions.ExtensionsEnvironment;
import net.sf.jasperreports.extensions.ExtensionsRegistry;
import org.apache.commons.collections.map.ReferenceMap;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* Class the provides access to {@link XmlValueHandler XML value handlers}.
*
* @author Lucian Chirita ([email protected])
*/
public class XmlValueHandlerUtils
{
private static final Log log = LogFactory.getLog(XmlValueHandlerUtils.class);
private static final XmlValueHandlerUtils INSTANCE = new XmlValueHandlerUtils();
/**
* Returns the singleton instance.
*
* @return the singleton instance
*/
public static XmlValueHandlerUtils instance()
{
return INSTANCE;
}
private final ReferenceMap cache;
private XmlValueHandlerUtils()
{
cache = new ReferenceMap(ReferenceMap.WEAK, ReferenceMap.HARD);
}
/**
* Returns the list of XML value handlers.
*
* @return the list of XML value handlers
*/
public List getHandlers()
{
Object cacheKey = ExtensionsEnvironment.getExtensionsCacheKey();
synchronized (cache)
{
@SuppressWarnings("unchecked")
List handlers = (List) cache.get(cacheKey);
if (handlers == null)
{
ExtensionsRegistry extensionsRegistry = ExtensionsEnvironment.getExtensionsRegistry();
handlers = extensionsRegistry.getExtensions(XmlValueHandler.class);
cache.put(cacheKey, handlers);
}
return handlers;
}
}
/**
* Outputs the XML representation of a value if the value is supported by any handler.
*
* @param value the value
* @param exporter the exporter
* @return true
iff a handler that supports the value was found
* @throws IOException
* @see XmlValueHandler#writeToXml(Object, JRXmlExporter)
*/
public boolean writeToXml(Object value, JRXmlExporter exporter) throws IOException
{
for (XmlValueHandler handler : getHandlers())
{
if (handler.writeToXml(value, exporter))
{
if (log.isDebugEnabled())
{
log.debug("Handler " + handler + " wrote value " + value);
}
return true;
}
}
if (log.isDebugEnabled())
{
log.debug("No handler wrote value " + value);
}
return false;
}
}