INT-926 inner handler beans are now created with prototype scope to avoid shared singleton for multiple inheritors of same abstract parent (see tests in this commit for an example).

org.springframework.integration/src/main/java/org/springframework/integration/config/xml/ChainParser.java

@@ -65,13 +65,14 @@ public class ChainParser extends AbstractConsumerEndpointParser {
 				parserContext.getReaderContext().error("child BeanDefinition must not be null", element);
 			}
 			else {
-				String beanName = BeanDefinitionReaderUtils.generateBeanName(beanDefinition, parserContext.getRegistry());
+				String beanName = BeanDefinitionReaderUtils.generateBeanName(beanDefinition, parserContext.getRegistry(), true);
 				holder = new BeanDefinitionHolder(beanDefinition, beanName);
 			}
 		}
 		if (holder == null) {
 			return null;
 		}
+		holder.getBeanDefinition().setScope(BeanDefinition.SCOPE_PROTOTYPE);
 		BeanDefinitionReaderUtils.registerBeanDefinition(holder, parserContext.getRegistry());
 		return holder.getBeanName();
 	}

org.springframework.integration/src/test/java/org/springframework/integration/config/xml/NestedChainParserTests-context.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans:beans xmlns="http://www.springframework.org/schema/integration"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:beans="http://www.springframework.org/schema/beans"
+	xsi:schemaLocation="http://www.springframework.org/schema/beans
+			http://www.springframework.org/schema/beans/spring-beans.xsd
+			http://www.springframework.org/schema/integration
+			http://www.springframework.org/schema/integration/spring-integration.xsd">
+
+	<beans:bean id="abstractParent" class="org.springframework.integration.config.xml.NestedChainParserTests$ParentTestBean" abstract="true">
+		<beans:property name="chain">
+			<chain>
+				<service-activator ref="service"/>
+			</chain>
+		</beans:property>
+	</beans:bean>
+
+	<beans:bean id="concreteParent1" parent="abstractParent"/>
+
+	<beans:bean id="concreteParent2" parent="abstractParent"/>
+
+	<beans:bean id="service" class="org.springframework.integration.config.xml.NestedChainParserTests$ChildTestBean"/>
+
+</beans:beans>

org.springframework.integration/src/test/java/org/springframework/integration/config/xml/NestedChainParserTests.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2002-2009 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.config.xml;
+
+import static org.junit.Assert.assertNotSame;
+
+import java.util.List;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.beans.DirectFieldAccessor;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.ApplicationContext;
+import org.springframework.integration.handler.MessageHandlerChain;
+import org.springframework.integration.message.MessageHandler;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+/**
+ * @author Mark Fisher
+ */
+@ContextConfiguration
+@RunWith(SpringJUnit4ClassRunner.class)
+public class NestedChainParserTests {
+
+	@Autowired
+	private ApplicationContext context;
+
+	@Test
+	public void chainsAreNotSame() {
+		ParentTestBean bean1 = context.getBean("concreteParent1", ParentTestBean.class);
+		ParentTestBean bean2 = context.getBean("concreteParent2", ParentTestBean.class);
+		assertNotSame(bean1, bean2);
+		assertNotSame(bean1.chain, bean2.chain);
+	}
+
+	@Test
+	@SuppressWarnings("unchecked")
+	public void handlersAreNotSame() {
+		ParentTestBean bean1 = context.getBean("concreteParent1", ParentTestBean.class);
+		ParentTestBean bean2 = context.getBean("concreteParent2", ParentTestBean.class);
+		List<MessageHandler> handlerList1 = (List<MessageHandler>) new DirectFieldAccessor(bean1.chain).getPropertyValue("handlers");
+		List<MessageHandler> handlerList2 = (List<MessageHandler>) new DirectFieldAccessor(bean2.chain).getPropertyValue("handlers");
+		MessageHandler handler1 = handlerList1.get(0);
+		MessageHandler handler2 = handlerList2.get(0);
+		assertNotSame(handler1, handler2);
+	}
+
+
+	static class ParentTestBean {
+
+		private MessageHandlerChain chain;
+
+		public void setChain(MessageHandlerChain chain) {
+			this.chain = chain;
+		}
+	}
+
+
+	static class ChildTestBean {
+
+		public String echo(String s) {
+			return s;
+		}
+	}
+
+}