net.sf.jasperreports.extensions.DefaultExtensionsRegistry Maven / Gradle / Ivy
/*
* JasperReports - Free Java Reporting Library.
* Copyright (C) 2001 - 2023 Cloud Software Group, 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.
*/
@Property(
name = "net.sf.jasperreports.extension.registry.factory.{arbitrary_name}",
category = PropertyConstants.CATEGORY_EXTENSIONS,
scopes = {PropertyScope.EXTENSION},
sinceVersion = PropertyConstants.VERSION_3_1_0
)
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.
*/
@Property(
name = "net.sf.jasperreports.extension.{registry_id}.{property_suffix}",
category = PropertyConstants.CATEGORY_EXTENSIONS,
scopes = {PropertyScope.EXTENSION},
sinceVersion = PropertyConstants.VERSION_3_1_0
)
public static final String PROPERTY_REGISTRY_PREFIX =
JRPropertiesUtil.PROPERTY_PREFIX + "extension.";
private final ReferenceMap> registrySetCache =
new ReferenceMap<>(
ReferenceMap.ReferenceStrength.WEAK, ReferenceMap.ReferenceStrength.HARD
);
private final ReferenceMap> registryCache =
new ReferenceMap<>(
ReferenceMap.ReferenceStrength.WEAK, ReferenceMap.ReferenceStrength.HARD
);
@Override
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 = 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()
{
//there is no identity linked hash map/set, using separate map and list
IdentityHashMap registrySet = new IdentityHashMap<>();
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;
Map registryExceptions = new LinkedHashMap<>();
synchronized (classLoaderRegistries)
{
URLRegistries urlRegistries = classLoaderRegistries.get(url);
if (urlRegistries == null)
{
if (log.isDebugEnabled())
{
log.debug("Loading JasperReports extension properties resource "
+ url);
}
JRPropertiesMap properties = JRPropertiesMap.loadProperties(url);
URL duplicateURL = detectDuplicate(properties, classLoaderRegistries);//search across classloaders?
if (duplicateURL == null)
{
registries = loadRegistries(properties, registryExceptions);
}
else
{
log.warn("Extension resource " + url + " was found to be a duplicate of "
+ duplicateURL + " in classloader " + classLoader);
registries = Collections.emptyList();
}
classLoaderRegistries.put(url, new URLRegistries(properties, registries));
}
else
{
registries = urlRegistries.registries;
}
}
for (Map.Entry entry : registryExceptions.entrySet())
{
log.error("Error instantiating extensions registry for "
+ entry.getKey() + " from " + url, entry.getValue());
}
for (ExtensionsRegistry extensionsRegistry : registries)
{
//detecting identity duplicates
boolean added = registrySet.put(extensionsRegistry, Boolean.FALSE) == null;
if (added)
{
allRegistries.add(extensionsRegistry);
}
else if (log.isDebugEnabled())
{
log.debug("Found duplicate extension registry " + extensionsRegistry);
}
}
}
return allRegistries;
}
protected List loadExtensionPropertyResources()
{
return JRLoader.getClassLoaderResources(
EXTENSION_RESOURCE_NAME);
}
protected Map getClassLoaderRegistries(ClassLoader classLoader)
{
synchronized (registryCache)
{
Map registries = registryCache.get(classLoader);
if (registries == null)
{
registries = new HashMap<>();
registryCache.put(classLoader, registries);
}
return registries;
}
}
protected List loadRegistries(JRPropertiesMap properties,
Map registryExceptions)
{
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
//error logging is deferred after the registries are cached to avoid a loop from JRRuntimeException.resolveMessage
registryExceptions.put(registryId, 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);
}
protected URL detectDuplicate(JRPropertiesMap properties, Map registries)
{
URL duplicateURL = null;
for (Entry registryEntry : registries.entrySet())
{
JRPropertiesMap entryProperties = registryEntry.getValue().properties;
if (ObjectUtils.equals(properties, entryProperties))
{
duplicateURL = registryEntry.getKey();
break;
}
}
return duplicateURL;
}
protected static class URLRegistries
{
JRPropertiesMap properties;
List registries;
public URLRegistries(JRPropertiesMap properties, List registries)
{
this.properties = properties;
this.registries = registries;
}
}
}