org.springframework.remoting.support.RemoteExporter 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.springframework.remoting.support;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.aop.framework.ProxyFactory;
/**
* Abstract base class for classes that export a remote service.
* Provides "service" and "serviceInterface" bean properties.
*
* Note that the service interface being used will show some signs of
* remotability, like the granularity of method calls that it offers.
* Furthermore, it has to have serializable arguments etc.
*
* @author Juergen Hoeller
* @since 26.12.2003
*/
public abstract class RemoteExporter {
protected final Log logger = LogFactory.getLog(getClass());
private Object service;
private Class serviceInterface;
/**
* Set the service to export.
* Typically populated via a bean reference.
*/
public void setService(Object service) {
this.service = service;
}
/**
* Return the service to export.
*/
protected Object getService() {
return service;
}
/**
* Set the interface of the service to export.
* The interface must be suitable for the particular service and remoting tool.
*/
public void setServiceInterface(Class serviceInterface) {
if (serviceInterface != null && !serviceInterface.isInterface()) {
throw new IllegalArgumentException("serviceInterface must be an interface");
}
this.serviceInterface = serviceInterface;
}
/**
* Return the interface of the service to export.
*/
protected Class getServiceInterface() {
return serviceInterface;
}
/**
* Check whether the service reference has been set.
* @see #setService
*/
protected void checkService() throws IllegalArgumentException {
if (this.service == null) {
throw new IllegalArgumentException("service is required");
}
}
/**
* Check whether a service reference has been set,
* and whether it matches the specified service.
* @see #setServiceInterface
* @see #setService
*/
protected void checkServiceInterface() throws IllegalArgumentException {
if (this.serviceInterface == null) {
throw new IllegalArgumentException("serviceInterface is required");
}
if (!this.serviceInterface.isInstance(this.service)) {
throw new IllegalArgumentException(
"serviceInterface [" + this.serviceInterface.getName() +
"] needs to be implemented by service [" + this.service + "]");
}
}
/**
* Get a proxy for the given service object, implementing the specified
* service interface.
*
Used to export a proxy that does not expose any internals but just
* a specific interface intended for remote access. Typically only applied
* if the remoting tool itself does not offer such means itself.
* @return the proxy
* @see #setServiceInterface
*/
protected Object getProxyForService() {
checkService();
checkServiceInterface();
ProxyFactory proxyFactory = new ProxyFactory();
proxyFactory.addInterface(getServiceInterface());
proxyFactory.setTarget(getService());
return proxyFactory.getProxy();
}
}