net.sf.jasperreports.extensions.DefaultExtensionsRegistry 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
* The implementation builds an extension registry by scanning the context
* classloader for resources named jasperreports_extension.properties.
*
*
* Each such resource is loaded as a properties file, and properties that start
* with {@link #PROPERTY_REGISTRY_FACTORY_PREFIX net.sf.jasperreports.extension.registry.factory.} are identified.
*
*
* Each such property should have as value the name of a
* {@link ExtensionsRegistryFactory} implementation. The registry factory class is
* instantiated, and
* {@link ExtensionsRegistryFactory#createRegistry(String, JRPropertiesMap)}
* is called on it, using the propery suffix as registry ID and passing the
* properties map. The registry factory can collect properties that apply to the
* specific registry by using a property prefix obtain by appending the registry ID
* to "{@link #PROPERTY_REGISTRY_PREFIX net.sf.jasperreports.extension.}".
*
*
* If instantiating an extension registry results in an exception, the registry
* is skipped and an error message is logged.
*
* @author Lucian Chirita ([email protected])
*/
public class DefaultExtensionsRegistry implements ExtensionsRegistry
{
private final Log log = LogFactory.getLog(DefaultExtensionsRegistry.class);
/**
* The name of property file resources that are used to load JasperReports
* extensions.
*/
public final static String EXTENSION_RESOURCE_NAME =
"jasperreports_extension.properties";
/**
* The property prefix of extension registry factories.
*/
public final static String PROPERTY_REGISTRY_FACTORY_PREFIX =
JRPropertiesUtil.PROPERTY_PREFIX + "extension.registry.factory.";
/**
* A prefix that can be used to provide registry-specific properties,
* by appending the registry ID and a fixed property suffix to it.
*/
public static final String PROPERTY_REGISTRY_PREFIX =
JRPropertiesUtil.PROPERTY_PREFIX + "extension.";
private final ReferenceMap registrySetCache = new ReferenceMap(
ReferenceMap.WEAK, ReferenceMap.HARD);
private final ReferenceMap registryCache =
new ReferenceMap(ReferenceMap.WEAK, ReferenceMap.HARD);
public List getExtensions(Class extensionType)
{
List registries = getRegistries();
List extensions = new ArrayList(registries.size());
for (Iterator it = registries.iterator(); it.hasNext();)
{
ExtensionsRegistry registry = it.next();
List registryExtensions = registry.getExtensions(extensionType);
if (registryExtensions != null && !registryExtensions.isEmpty())
{
extensions.addAll(registryExtensions);
}
}
return extensions;
}
protected List getRegistries()
{
List registries;
Object cacheKey = ExtensionsEnvironment.getExtensionsCacheKey();
synchronized (registrySetCache)
{
registries = (List) registrySetCache.get(cacheKey);
if (registries == null)
{
if (log.isDebugEnabled())
{
log.debug("Loading registries for cache key " + cacheKey);
}
registries = loadRegistries();
registrySetCache.put(cacheKey, registries);
}
}
return registries;
}
protected List loadRegistries()
{
List allRegistries = new ArrayList();
List extensionResources = loadExtensionPropertyResources();
for (ClassLoaderResource extensionResource : extensionResources)
{
ClassLoader classLoader = extensionResource.getClassLoader();
Map> classLoaderRegistries = getClassLoaderRegistries(classLoader);
URL url = extensionResource.getUrl();
List registries;
synchronized (classLoaderRegistries)
{
registries = classLoaderRegistries.get(url);
if (registries == null)
{
if (log.isDebugEnabled())
{
log.debug("Loading JasperReports extension properties resource "
+ url);
}
registries = loadRegistries(url);
classLoaderRegistries.put(url, registries);
}
}
allRegistries.addAll(registries);
}
return allRegistries;
}
protected List loadExtensionPropertyResources()
{
return JRLoader.getClassLoaderResources(
EXTENSION_RESOURCE_NAME);
}
protected Map> getClassLoaderRegistries(ClassLoader classLoader)
{
synchronized (registryCache)
{
Map> registries = (Map>) registryCache.get(classLoader);
if (registries == null)
{
registries = new HashMap>();
registryCache.put(classLoader, registries);
}
return registries;
}
}
protected List loadRegistries(URL url)
{
JRPropertiesMap properties = JRPropertiesMap.loadProperties(url);
List registries = new ArrayList();
List factoryProps = JRPropertiesUtil.getProperties(properties,
PROPERTY_REGISTRY_FACTORY_PREFIX);
for (Iterator it = factoryProps.iterator(); it.hasNext();)
{
PropertySuffix factoryProp = it.next();
String registryId = factoryProp.getSuffix();
String factoryClass = factoryProp.getValue();
if (log.isDebugEnabled())
{
log.debug("Instantiating registry of type " + factoryClass
+ " for property " + factoryProp.getKey());
}
try
{
ExtensionsRegistry registry = instantiateRegistry(
properties, registryId, factoryClass);
registries.add(registry);
}
catch (Exception e)
{
//skip this registry
log.error("Error instantiating extensions registry for "
+ registryId + " from " + url, e);
}
}
return registries;
}
protected ExtensionsRegistry instantiateRegistry(
JRPropertiesMap props, String registryId, String factoryClass)
{
if (log.isDebugEnabled())
{
log.debug("Instantiating extensions registry for " + registryId
+ " using factory class " + factoryClass);
}
ExtensionsRegistryFactory factory = (ExtensionsRegistryFactory)
ClassUtils.instantiateClass(factoryClass, ExtensionsRegistryFactory.class);
return factory.createRegistry(registryId, props);
}
}