/*
 * Copyright 2002-2017 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
 *
 *      https://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.jmx.access;

import org.springframework.aop.framework.ProxyFactory;
import org.springframework.beans.factory.BeanClassLoaderAware;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.jmx.MBeanServerNotFoundException;
import org.springframework.lang.Nullable;
import org.springframework.util.ClassUtils;

Creates a proxy to a managed resource running either locally or remotely.
The "proxyInterface" property defines the interface that the generated
proxy is supposed to implement. This interface should define methods and
properties that correspond to operations and attributes in the management
interface of the resource you wish to proxy.
There is no need for the managed resource to implement the proxy interface,
although you may find it convenient to do. It is not required that every
operation and attribute in the management interface is matched by a
corresponding property or method in the proxy interface.
Attempting to invoke or access any method or property on the proxy interface that does not correspond to the management interface will lead to an InvalidInvocationException. 
Author:
Rob Harrop, Juergen Hoeller
See Also:
MBeanClientInterceptor
InvalidInvocationException
Since:
1.2/**
 * Creates a proxy to a managed resource running either locally or remotely.
 * The "proxyInterface" property defines the interface that the generated
 * proxy is supposed to implement. This interface should define methods and
 * properties that correspond to operations and attributes in the management
 * interface of the resource you wish to proxy.
 *
 * <p>There is no need for the managed resource to implement the proxy interface,
 * although you may find it convenient to do. It is not required that every
 * operation and attribute in the management interface is matched by a
 * corresponding property or method in the proxy interface.
 *
 * <p>Attempting to invoke or access any method or property on the proxy
 * interface that does not correspond to the management interface will lead
 * to an {@code InvalidInvocationException}.
 *
 * @author Rob Harrop
 * @author Juergen Hoeller
 * @since 1.2
 * @see MBeanClientInterceptor
 * @see InvalidInvocationException
 */
public class MBeanProxyFactoryBean extends MBeanClientInterceptor
		implements FactoryBean<Object>, BeanClassLoaderAware, InitializingBean {

	@Nullable
	private Class<?> proxyInterface;

	@Nullable
	private ClassLoader beanClassLoader = ClassUtils.getDefaultClassLoader();

	@Nullable
	private Object mbeanProxy;


	
Set the interface that the generated proxy will implement.
This will usually be a management interface that matches the target MBean,
exposing bean property setters and getters for MBean attributes and
conventional Java methods for MBean operations.
See Also:
setObjectName/**
	 * Set the interface that the generated proxy will implement.
	 * <p>This will usually be a management interface that matches the target MBean,
	 * exposing bean property setters and getters for MBean attributes and
	 * conventional Java methods for MBean operations.
	 * @see #setObjectName
	 */
	public void setProxyInterface(Class<?> proxyInterface) {
		this.proxyInterface = proxyInterface;
	}

	@Override
	public void setBeanClassLoader(ClassLoader classLoader) {
		this.beanClassLoader = classLoader;
	}

	
Checks that the proxyInterface has been specified and then generates the proxy for the target MBean. /**
	 * Checks that the {@code proxyInterface} has been specified and then
	 * generates the proxy for the target MBean.
	 */
	@Override
	public void afterPropertiesSet() throws MBeanServerNotFoundException, MBeanInfoRetrievalException {
		super.afterPropertiesSet();

		if (this.proxyInterface == null) {
			this.proxyInterface = getManagementInterface();
			if (this.proxyInterface == null) {
				throw new IllegalArgumentException("Property 'proxyInterface' or 'managementInterface' is required");
			}
		}
		else {
			if (getManagementInterface() == null) {
				setManagementInterface(this.proxyInterface);
			}
		}
		this.mbeanProxy = new ProxyFactory(this.proxyInterface, this).getProxy(this.beanClassLoader);
	}


	@Override
	@Nullable
	public Object getObject() {
		return this.mbeanProxy;
	}

	@Override
	public Class<?> getObjectType() {
		return this.proxyInterface;
	}

	@Override
	public boolean isSingleton() {
		return true;
	}

}