/*
 * 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
 *
 *      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.beans.factory.config;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.util.ClassUtils;
import org.springframework.util.StringUtils;

Bean factory post processor that logs a warning for @Deprecated beans. 
Author:
Arjen Poutsma
Since:
3.0.3/**
 * Bean factory post processor that logs a warning for {@link Deprecated @Deprecated} beans.
 *
 * @author Arjen Poutsma
 * @since 3.0.3
 */
public class DeprecatedBeanWarner implements BeanFactoryPostProcessor {

	
Logger available to subclasses.
/**
	 * Logger available to subclasses.
	 */
	protected transient Log logger = LogFactory.getLog(getClass());

	
Set the name of the logger to use.
The name will be passed to the underlying logger implementation through Commons Logging,
getting interpreted as log category according to the logger's configuration.
This can be specified to not log into the category of this warner class but rather
into a specific named category.
See Also:
getLog.getLog(String)
Logger.getLogger(String)/**
	 * Set the name of the logger to use.
	 * The name will be passed to the underlying logger implementation through Commons Logging,
	 * getting interpreted as log category according to the logger's configuration.
	 * <p>This can be specified to not log into the category of this warner class but rather
	 * into a specific named category.
	 * @see org.apache.commons.logging.LogFactory#getLog(String)
	 * @see java.util.logging.Logger#getLogger(String)
	 */
	public void setLoggerName(String loggerName) {
		this.logger = LogFactory.getLog(loggerName);
	}


	@Override
	public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
		if (isLogEnabled()) {
			String[] beanNames = beanFactory.getBeanDefinitionNames();
			for (String beanName : beanNames) {
				String nameToLookup = beanName;
				if (beanFactory.isFactoryBean(beanName)) {
					nameToLookup = BeanFactory.FACTORY_BEAN_PREFIX + beanName;
				}
				Class<?> beanType = beanFactory.getType(nameToLookup);
				if (beanType != null) {
					Class<?> userClass = ClassUtils.getUserClass(beanType);
					if (userClass.isAnnotationPresent(Deprecated.class)) {
						BeanDefinition beanDefinition = beanFactory.getBeanDefinition(beanName);
						logDeprecatedBean(beanName, beanType, beanDefinition);
					}
				}
			}
		}
	}

	
Logs a warning for a bean annotated with @Deprecated. 
Params:
beanName – the name of the deprecated bean
beanType – the user-specified type of the deprecated bean
beanDefinition – the definition of the deprecated bean/**
	 * Logs a warning for a bean annotated with {@link Deprecated @Deprecated}.
	 * @param beanName the name of the deprecated bean
	 * @param beanType the user-specified type of the deprecated bean
	 * @param beanDefinition the definition of the deprecated bean
	 */
	protected void logDeprecatedBean(String beanName, Class<?> beanType, BeanDefinition beanDefinition) {
		StringBuilder builder = new StringBuilder();
		builder.append(beanType);
		builder.append(" ['");
		builder.append(beanName);
		builder.append('\'');
		String resourceDescription = beanDefinition.getResourceDescription();
		if (StringUtils.hasLength(resourceDescription)) {
			builder.append(" in ");
			builder.append(resourceDescription);
		}
		builder.append("] has been deprecated");
		writeToLog(builder.toString());
	}

	
Actually write to the underlying log.
The default implementations logs the message at "warn" level.
Params:
message – the message to write/**
	 * Actually write to the underlying log.
	 * <p>The default implementations logs the message at "warn" level.
	 * @param message the message to write
	 */
	protected void writeToLog(String message) {
		logger.warn(message);
	}

	
Determine whether the logger field is enabled. 
Default is true when the "warn" level is enabled. Subclasses can override this to change the level under which logging occurs. /**
	 * Determine whether the {@link #logger} field is enabled.
	 * <p>Default is {@code true} when the "warn" level is enabled.
	 * Subclasses can override this to change the level under which logging occurs.
	 */
	protected boolean isLogEnabled() {
		return logger.isWarnEnabled();
	}

}