From 355a8e70e995541f22f85b78fbdf2cefc314ce69 Mon Sep 17 00:00:00 2001
From: Mark Fisher <markfisher@vmware.com>
Date: Wed, 17 Dec 2008 13:25:05 +0000
Subject: [PATCH] Refactored error-handling demo to use a chain with a
 transformer instead of the channel-interceptor.

---
 ...geTransformer.java => ErrorUnwrapper.java} | 18 +++++++----
 .../samples/errorhandling/Invitation.java     |  5 ++++
 .../samples/errorhandling/PartyDemo.java      | 10 +++----
 .../samples/errorhandling/PartyGuest.java     |  4 ++-
 .../samples/errorhandling/PartyHost.java      | 10 +++----
 .../errorhandling/errorHandlingDemo.xml       | 30 +++++++------------
 6 files changed, 40 insertions(+), 37 deletions(-)
 rename org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/{UnwrappingErrorMessageTransformer.java => ErrorUnwrapper.java} (69%)

diff --git a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/UnwrappingErrorMessageTransformer.java b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/ErrorUnwrapper.java
similarity index 69%
rename from org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/UnwrappingErrorMessageTransformer.java
rename to org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/ErrorUnwrapper.java
index dca3b33d45..f940c57870 100644
--- a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/UnwrappingErrorMessageTransformer.java
+++ b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/ErrorUnwrapper.java
@@ -12,18 +12,24 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.integration.samples.errorhandling;
 
+import org.springframework.integration.annotation.MessageEndpoint;
+import org.springframework.integration.annotation.Transformer;
 import org.springframework.integration.core.Message;
 import org.springframework.integration.core.MessagingException;
 import org.springframework.integration.message.ErrorMessage;
-import org.springframework.integration.transformer.Transformer;
-import org.springframework.util.Assert;
 
-public class UnwrappingErrorMessageTransformer implements Transformer {
+/**
+ * @author Iwein Fuld
+ */
+@MessageEndpoint
+public class ErrorUnwrapper {
 
-	public Message<?> transform(Message<?> message) {
-		Assert.isAssignable(ErrorMessage.class, message.getClass());
-		return ((MessagingException) ((ErrorMessage) message).getPayload()).getFailedMessage();
+	@Transformer
+	public Message<?> transform(ErrorMessage errorMessage) {
+		return ((MessagingException) errorMessage.getPayload()).getFailedMessage();
 	}
+
 }
diff --git a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/Invitation.java b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/Invitation.java
index 79b97b5604..e9e3dbf028 100644
--- a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/Invitation.java
+++ b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/Invitation.java
@@ -12,8 +12,12 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.integration.samples.errorhandling;
 
+/**
+ * @author Iwein Fuld
+ */
 public class Invitation {
 
 	private final int number;
@@ -26,4 +30,5 @@ public class Invitation {
 	public String toString() {
 		return "Invitation number " + number;
 	}
+
 }
diff --git a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyDemo.java b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyDemo.java
index 6f1919653c..0fdfec2d10 100644
--- a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyDemo.java
+++ b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyDemo.java
@@ -12,18 +12,18 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.integration.samples.errorhandling;
 
 import org.springframework.context.support.ClassPathXmlApplicationContext;
 
+/**
+ * @author Iwein Fuld
+ */
 public class PartyDemo {
 
-	/**
-	 * @param args
-	 */
 	public static void main(String[] args) {
-		new ClassPathXmlApplicationContext("errorHandlingDemo.xml", PartyDemo.class).start();
-
+		new ClassPathXmlApplicationContext("errorHandlingDemo.xml", PartyDemo.class);
 	}
 
 }
diff --git a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyGuest.java b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyGuest.java
index 7b6e2aced0..54ab6aa0e4 100644
--- a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyGuest.java
+++ b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyGuest.java
@@ -12,6 +12,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.integration.samples.errorhandling;
 
 import org.springframework.integration.annotation.MessageEndpoint;
@@ -21,12 +22,13 @@ import org.springframework.integration.annotation.MessageEndpoint;
  * address exception message.
  * 
  * @author Iwein Fuld
- * 
  */
 @MessageEndpoint
 public class PartyGuest {
+
 	public void onInvitation(Invitation invitation) {
 		System.out.println("Guest is throwing exception");
 		throw new RuntimeException("Wrong address");
 	}
+
 }
diff --git a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyHost.java b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyHost.java
index 92e7661d9a..2d18e8ef60 100644
--- a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyHost.java
+++ b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/PartyHost.java
@@ -12,6 +12,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.integration.samples.errorhandling;
 
 import java.util.concurrent.atomic.AtomicInteger;
@@ -19,19 +20,18 @@ import java.util.concurrent.atomic.AtomicInteger;
 import org.springframework.integration.annotation.MessageEndpoint;
 
 /**
- * Sends invitations to <code>Guest</code>s and likes to be notified of delivery
- * failures of course.
+ * Sends invitations to <code>PartyGuest</code>s and likes to be notified of
+ * delivery failures of course.
  * 
  * @author Iwein Fuld
- * 
  */
 @MessageEndpoint
 public class PartyHost {
 
-	private final AtomicInteger counter = new AtomicInteger(1);
+	private final AtomicInteger counter = new AtomicInteger(0);
 
 	public Invitation nextInvitation() {
-		return new Invitation(counter.getAndIncrement());
+		return new Invitation(counter.incrementAndGet());
 	}
 
 	public void onInvitationFailed(Invitation inv) {
diff --git a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/errorHandlingDemo.xml b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/errorHandlingDemo.xml
index f9963032a7..c1d0c8d654 100644
--- a/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/errorHandlingDemo.xml
+++ b/org.springframework.integration.samples/src/main/java/org/springframework/integration/samples/errorhandling/errorHandlingDemo.xml
@@ -11,15 +11,14 @@
 			http://www.springframework.org/schema/integration/spring-integration-1.0.xsd
 			http://www.springframework.org/schema/integration/stream
 			http://www.springframework.org/schema/integration/stream/spring-integration-stream-1.0.xsd">
-	<context:component-scan
-		base-package="org.springframework.integration.samples.errorhandling" />
 
-	<poller id="jack" default="true">
+	<context:component-scan base-package="org.springframework.integration.samples.errorhandling" />
+
+	<poller default="true" max-messages-per-poll="1">
 		<interval-trigger interval="1000" />
 	</poller>
 
-	<inbound-channel-adapter ref="partyHost"
-		auto-startup="true" method="nextInvitation" channel="invitations" />
+	<inbound-channel-adapter ref="partyHost" method="nextInvitation" channel="invitations" />
 
 	<channel id="invitations">
 		<queue capacity="100" />
@@ -30,22 +29,13 @@
 		<service-activator ref="partyGuest" method="onInvitation" />
 	</chain>
 
-	<channel id="failed-invitations">
-		<interceptors>
-			<beans:bean
-				class="org.springframework.integration.transformer.MessageTransformingChannelInterceptor">
-				<beans:constructor-arg>
-					<beans:bean
-						class="org.springframework.integration.samples.errorhandling.UnwrappingErrorMessageTransformer" />
-				</beans:constructor-arg>
-			</beans:bean>
-		</interceptors>
-	</channel>
+	<channel id="failed-invitations" />
 
-	<service-activator ref="partyHost" method="onInvitationFailed"
-		input-channel="failed-invitations" />
+	<chain input-channel="failed-invitations">
+		<transformer ref="errorUnwrapper" />
+		<service-activator ref="partyHost" method="onInvitationFailed" />
+	</chain>
 
-	<stream:stderr-channel-adapter channel="errorChannel"
-		append-newline="true" />
+	<stream:stderr-channel-adapter channel="errorChannel" append-newline="true" />
 
 </beans:beans>
\ No newline at end of file