INT-1923 refactored to simplify code (removed ResubmittingTask, fixed the use of TaskExecutor, other minor polishing)

spring-integration-mail/src/main/java/org/springframework/integration/mail/ImapIdleChannelAdapter.java

@@ -57,8 +57,6 @@ public class ImapIdleChannelAdapter extends MessageProducerSupport {
 	private volatile ScheduledFuture<?> receivingTask;
 	private volatile ScheduledFuture<?> pingTask;
 	
-	private volatile ResubmittingTask task;
-	
 	private volatile long connectionPingInterval = 10000;
 
 	public ImapIdleChannelAdapter(ImapMailReceiver mailReceiver) {
@@ -73,7 +71,7 @@ public class ImapIdleChannelAdapter extends MessageProducerSupport {
 	public void setShouldReconnectAutomatically(boolean shouldReconnectAutomatically) {
 		this.shouldReconnectAutomatically = shouldReconnectAutomatically;
 	}
-
+    
 	public void setTaskExecutor(Executor taskExecutor) {
 		this.taskExecutor = taskExecutor;
 	}
@@ -93,12 +91,25 @@ public class ImapIdleChannelAdapter extends MessageProducerSupport {
 
 	@Override // guarded by super#lifecycleLock
 	protected void doStart() {
-		TaskScheduler scheduler =  this.getTaskScheduler();
+		final TaskScheduler scheduler =  this.getTaskScheduler();
 		Assert.notNull(scheduler, "'taskScheduler' must not be null" );
-		this.task = new ResubmittingTask(this.idleTask, scheduler, reconnectDelay);
-		task.setTaskExecutor(taskExecutor);
 		
-		receivingTask = scheduler.schedule(task, new Date());
+		receivingTask = scheduler.scheduleAtFixedRate(new Runnable(){
+
+			public void run() {
+				try {
+					idleTask.run();
+					if (logger.isDebugEnabled()){
+						logger.debug("Task completed successfully. Re-scheduling it again right away");
+					}
+				}
+				catch (IllegalStateException e) { //run again after a delay
+					logger.warn("Failed to execute IDLE task. Will atempt to resubmit in " + reconnectDelay + " milliseconds", e);
+					scheduler.scheduleAtFixedRate(this, new Date(System.currentTimeMillis() + reconnectDelay), 1);	
+				}
+			}
+			
+		}, 1);
 		
 		pingTask = scheduler.scheduleAtFixedRate(new Runnable() {	
 			public void run() {
@@ -116,7 +127,6 @@ public class ImapIdleChannelAdapter extends MessageProducerSupport {
 
 	@Override // guarded by super#lifecycleLock
 	protected void doStop() {
-		this.task.requestStop();
 		receivingTask.cancel(true);
 		pingTask.cancel(true);		
 		try {
@@ -135,14 +145,23 @@ public class ImapIdleChannelAdapter extends MessageProducerSupport {
 					logger.debug("waiting for mail");
 				}
 				mailReceiver.waitForNewMessages();
-				if (!task.isStopRequested()){
+				if (mailReceiver.getFolder().isOpen()){
 					Message[] mailMessages = mailReceiver.receive();
 					if (logger.isDebugEnabled()) {
 						logger.debug("received " + mailMessages.length + " mail messages");
 					}
 					for (Message mailMessage : mailMessages) {
-						MimeMessage copied = new MimeMessage((MimeMessage) mailMessage);
-						sendMessage(MessageBuilder.withPayload(copied).build());
+						final MimeMessage copied = new MimeMessage((MimeMessage) mailMessage);
+						if (taskExecutor != null){
+							taskExecutor.execute(new Runnable() {		
+								public void run() {
+									sendMessage(MessageBuilder.withPayload(copied).build());
+								}
+							});
+						}
+						else {
+							sendMessage(MessageBuilder.withPayload(copied).build());
+						}
 					}
 				}			
 			} catch (MessagingException e) {

spring-integration-mail/src/main/java/org/springframework/integration/mail/ResubmittingTask.java

@@ -1,94 +0,0 @@
-/*
- * Copyright 2002-2011 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.integration.mail;
-
-import java.util.Date;
-import java.util.concurrent.Executor;
-
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-
-import org.springframework.core.task.SimpleAsyncTaskExecutor;
-import org.springframework.scheduling.TaskScheduler;
-
-/**
- * @author Mark Fisher
- * @author Oleg Zhurakousky
- * @since 2.0.2
- *
- * Will run the provided task right away resubmitting it after each successful execution 
- * or after receiving a {@link IllegalStateException}. If resubmission is after exception then 
- * the delay will be applied before resubmission. This is useful when the underlying task deals 
- * with reconnection logic 
- * Currently only used to manage IDLE task of ImapIdleChannelAdapter
- */
-class ResubmittingTask implements Runnable {
-	private static final Log logger = LogFactory.getLog(ResubmittingTask.class);
-	private final Runnable targetTask;
-	private final TaskScheduler scheduler;
-	private final long delay;
-	private Executor taskExecutor = new SimpleAsyncTaskExecutor();
-	
-	private volatile boolean stopRequested = false;
-	
-	public ResubmittingTask(Runnable targetTask, TaskScheduler scheduler, long delay) {
-		this.targetTask = targetTask;
-		this.scheduler = scheduler;
-		this.delay = delay;
-	}
-	
-	public void setTaskExecutor(Executor taskExecutor) {
-		this.taskExecutor = (taskExecutor != null) ? taskExecutor : new SimpleAsyncTaskExecutor();
-	}
-
-	public void run() {
-		taskExecutor.execute(new Runnable() {	
-			public void run() {
-				ResubmittingTask.this.invokeTask();
-			}
-		});	
-	}
-	
-	protected void requestStop(){
-		this.stopRequested = true;
-	}
-
-	protected boolean isStopRequested(){
-		return this.stopRequested;
-	}
-	
-	private void invokeTask(){
-		try {
-			targetTask.run();
-			if (!this.stopRequested){
-				if (logger.isDebugEnabled()){
-					logger.debug("Task completed successfully. Re-scheduling it again right away");
-				}
-				scheduler.schedule(this, new Date());
-			}
-			else {
-				if (logger.isDebugEnabled()){
-					logger.debug("IDLE Task is stopped");
-				}
-			}
-			
-		}
-		catch (IllegalStateException e) { //run again after a delay
-			logger.warn("Failed to execute IDLE task. Will atempt to resubmit in " + delay + " milliseconds", e);
-			scheduler.schedule(this, new Date(System.currentTimeMillis() + delay));	
-		}
-	}
-}

spring-integration-mail/src/main/resources/org/springframework/integration/mail/config/spring-integration-mail-2.0.xsd

@@ -107,7 +107,7 @@
 					<xsd:attribute name="task-executor" type="xsd:string">
 						<xsd:annotation>
 							<xsd:documentation>
-	Reference to a TaskExecutor for sending inbound Mail to a MessageChannel asynchronously.
+	Reference to a TaskExecutor which will be used to send inbound Mail to a MessageChannel.
 							</xsd:documentation>
 							<xsd:appinfo>
 								<tool:annotation kind="ref">

spring-integration-mail/src/test/java/log4j.properties

@@ -1,4 +1,4 @@
-log4j.rootCategory=WARN, stdout
+log4j.rootCategory=DEBUG, stdout
 
 log4j.appender.stdout=org.apache.log4j.ConsoleAppender
 log4j.appender.stdout.layout=org.apache.log4j.PatternLayout