/*
* Copyright 2006-2010 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.batch.item.mail;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import org.springframework.batch.item.ItemWriter;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.mail.MailException;
import org.springframework.mail.MailSendException;
import org.springframework.mail.MailSender;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.util.Assert;
/**
* <p>
* A simple {@link ItemWriter} that can send mail messages. If it fails there is
* no guarantee about which of the messages were sent, but the ones that failed
* can be picked up in the error handler. Because the mail protocol is not
* transactional, failures should be dealt with here if possible rather than
* allowing them to be rethrown (which is the default).
* </p>
*
* <p>
* Delegates the actual sending of messages to a {@link MailSender}, using the
* batch method {@link MailSender#send(SimpleMailMessage[])}, which normally
* uses a single server connection for the whole batch (depending on the
* implementation). The efficiency of for large volumes of messages (repeated
* calls to the item writer) might be improved by the use of a special
* {@link MailSender} that caches connections to the server in between calls.
* </p>
*
* <p>
* Stateless, so automatically restartable.
* </p>
*
* @author Dave Syer
*
* @since 2.1
*
*/
public class SimpleMailMessageItemWriter implements ItemWriter<SimpleMailMessage>, InitializingBean {
private MailSender mailSender;
private MailErrorHandler mailErrorHandler = new DefaultMailErrorHandler();
/**
* A {@link MailSender} to be used to send messages in {@link #write(List)}.
*
* @param mailSender
*/
public void setMailSender(MailSender mailSender) {
this.mailSender = mailSender;
}
/**
* The handler for failed messages. Defaults to a
* {@link DefaultMailErrorHandler}.
*
* @param mailErrorHandler the mail error handler to set
*/
public void setMailErrorHandler(MailErrorHandler mailErrorHandler) {
this.mailErrorHandler = mailErrorHandler;
}
/**
* Check mandatory properties (mailSender).
*
* @throws IllegalStateException if the mandatory properties are not set
*
* @see InitializingBean#afterPropertiesSet()
*/
@Override
public void afterPropertiesSet() throws IllegalStateException {
Assert.state(mailSender != null, "A MailSender must be provided.");
}
/**
* @param items the items to send
* @see ItemWriter#write(List)
*/
@Override
public void write(List<? extends SimpleMailMessage> items) throws MailException {
try {
mailSender.send(items.toArray(new SimpleMailMessage[items.size()]));
}
catch (MailSendException e) {
Map<Object, Exception> failedMessages = e.getFailedMessages();
for (Entry<Object, Exception> entry : failedMessages.entrySet()) {
mailErrorHandler.handle((SimpleMailMessage) entry.getKey(), entry.getValue());
}
}
}
}