org.jboss.weld.bootstrap.AdditionalServiceLoader Maven / Gradle / Ivy
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* Copyright 2014, Red Hat, Inc., and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jboss.weld.bootstrap;
import java.util.HashSet;
import java.util.Set;
import jakarta.annotation.Priority;
import org.jboss.weld.bootstrap.api.Service;
import org.jboss.weld.bootstrap.api.ServiceRegistry;
import org.jboss.weld.bootstrap.spi.BeanDeploymentArchive;
import org.jboss.weld.bootstrap.spi.Deployment;
import org.jboss.weld.bootstrap.spi.Metadata;
import org.jboss.weld.resources.DefaultResourceLoader;
import org.jboss.weld.resources.WeldClassLoaderResourceLoader;
import org.jboss.weld.resources.spi.ResourceLoader;
import org.jboss.weld.util.ServiceLoader;
import org.jboss.weld.util.Services;
/**
* Loads {@link Service} implementations using {@link ServiceLoader}.
*
*
* This can be used e.g. by a JTA library in weld-servlet environment to provide
* {@link org.jboss.weld.transaction.spi.TransactionServices} implementation which
* would not otherwise be provided by weld-servlet. Deployment classloaders, TCCL and Weld's classloader are used to discover
* service implementations. If a
* service provider is loadable from multiple classloaders (most likely in a Java SE application) the service class will be
* instantiated multiple times but only
* the first instance will be used (see {@link Services#put(ServiceRegistry, Class, Service)}).
*
*
*
* Service implementation may specify their priority using {@link Priority}. Services with higher priority have precedence.
* Services that do not specify
* priority have the default priority of 4500.
*
*
*
* Note that the loaded services are registered globally, i.e. are accessible from each bean manager in the application.
*
*
*
* See WELD-1495 for details.
*
*
* @author Jozef Hartinger
*/
class AdditionalServiceLoader {
private final Deployment deployment;
AdditionalServiceLoader(Deployment deployment) {
this.deployment = deployment;
}
/**
* Discovers additional services using {@link ServiceLoader} and appends them to the given service registry.
*
* @param registry the given service registry
*/
void loadAdditionalServices(ServiceRegistry registry) {
for (ResourceLoader loader : getResourceLoaders()) {
for (Metadata metadata : ServiceLoader.load(Service.class, loader)) {
Service service = metadata.getValue();
for (Class serviceInterface : Services.identifyServiceInterfaces(service.getClass(),
new HashSet<>())) {
Services.put(registry, serviceInterface, service);
}
}
}
}
private Set getResourceLoaders() {
Set resourceLoaders = new HashSet<>();
for (BeanDeploymentArchive archive : deployment.getBeanDeploymentArchives()) {
ResourceLoader resourceLoader = archive.getServices().get(ResourceLoader.class);
if (resourceLoader != null) {
resourceLoaders.add(resourceLoader);
}
}
resourceLoaders.add(WeldClassLoaderResourceLoader.INSTANCE);
resourceLoaders.add(DefaultResourceLoader.INSTANCE);
return resourceLoaders;
}
}