org.springmodules.hivemind.ServiceFactoryBean Maven / Gradle / Ivy
/*
* Copyright 2002-2004 the original author or authors.
*
* 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.springmodules.hivemind;
import org.apache.hivemind.Registry;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.context.ApplicationContextException;
import org.springframework.util.Assert;
/**
* FactoryBean implementation that acts as an adapter to a HiveMind Registry
* allowing for any HiveMind service to be exposed as a Spring bean.
*
* Both the serviceInterface and registry properties are required. By default,
* services are retreived from the HiveMind Registry using the service interface only.
* If a value is supplied for the serviceName property, then both the service interface
* and service name will be used when looking for the service in HiveMind.
*
* @author Rob Harrop
* @author Thierry Templier
* @see Registry
* @see RegistryFactoryBean
* @see #setServiceInterface(Class)
* @see #setServiceName(String)
* @see #setRegistry(org.apache.hivemind.Registry)
*/
public class ServiceFactoryBean implements FactoryBean, InitializingBean {
/**
* The HiveMind Registry from which services are accessed.
*/
private Registry registry;
/**
* The name of the HiveMind service to access.
*/
private String serviceName;
/**
* The Class name of the of the HiveMind service.
*/
private Class serviceInterface;
/**
* Sets the interface of the HiveMind service to be accessed.
*/
public void setServiceInterface(Class serviceInterface) {
Assert.isTrue(serviceInterface.isInterface(), "Cannot use a Class for the service interface");
this.serviceInterface = serviceInterface;
}
/**
* Sets the service name of the HiveMind service to be accessed.
*/
public void setServiceName(String serviceName) {
this.serviceName = serviceName;
}
/**
* Sets the HiveMind Registry used to load services.
*/
public void setRegistry(Registry registry) {
this.registry = registry;
}
/**
* Gets the Hivemind service from the Registry.
*/
public Object getObject() throws Exception {
return getServiceObject();
}
public Class getObjectType() {
// can we use singletons and cache here?
return getServiceObject().getClass();
}
public boolean isSingleton() {
return false;
}
/**
* Checks if the registry and serviceInterface properties are specified. If no corresponding service is
* configured in the Hivemind Registry, an ApplicationContextException is thrown.
*/
public void afterPropertiesSet() throws Exception {
if (registry == null) {
throw new ApplicationContextException("Property [registry] of class [" + ServiceFactoryBean.class
+ "] is required.");
}
if (serviceInterface == null) {
throw new ApplicationContextException("Property [serviceInterface] of class [" + ServiceFactoryBean.class
+ "] is required.");
}
// check that the service exists for fail fast behaviour
boolean containsService = false;
if (serviceName == null) {
containsService = registry.containsService(serviceInterface);
}
else {
containsService = registry.containsService(serviceName, serviceInterface);
}
if (!containsService) {
throw new ApplicationContextException("Service with interface [" + serviceInterface.getName() +
"] and name [" + serviceName + "] is not present in registry.");
}
}
/**
* Get the Hivemind service from the Registry.
*/
private Object getServiceObject() {
if (serviceName == null) {
return registry.getService(serviceInterface);
}
else {
return registry.getService(serviceName, serviceInterface);
}
}
}