Added unit test to check ConversationContainer size in the session.

spring-webflow/src/main/java/org/springframework/webflow/conversation/impl/ConversationContainer.java

@@ -56,6 +56,14 @@ class ConversationContainer implements Serializable {
 		this.maxConversations = maxConversations;
 		this.conversations = new ArrayList();
 	}
+	
+	/**
+	 * Returns the current size of the conversation container: the number
+	 * of conversations contained within it.
+	 */
+	public int size() {
+		return conversations.size();
+	}
 
 	/**
 	 * Create a new conversation based on given parameters and add it to the

spring-webflow/src/test/java/org/springframework/webflow/conversation/impl/ConversationSizeTests.java

@@ -0,0 +1,128 @@
+/*
+ * Copyright 2004-2007 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.webflow.conversation.impl;
+
+import java.io.ByteArrayOutputStream;
+import java.io.ObjectOutputStream;
+
+import junit.framework.TestCase;
+
+import org.springframework.beans.factory.support.StaticListableBeanFactory;
+import org.springframework.webflow.config.FlowExecutorFactoryBean;
+import org.springframework.webflow.config.RepositoryType;
+import org.springframework.webflow.core.collection.SharedAttributeMap;
+import org.springframework.webflow.definition.registry.FlowDefinitionRegistry;
+import org.springframework.webflow.engine.builder.AbstractFlowBuilder;
+import org.springframework.webflow.engine.builder.AbstractFlowBuilderFlowRegistryFactoryBean;
+import org.springframework.webflow.engine.builder.FlowBuilderException;
+import org.springframework.webflow.execution.support.ApplicationView;
+import org.springframework.webflow.execution.support.FlowExecutionRedirect;
+import org.springframework.webflow.executor.FlowExecutor;
+import org.springframework.webflow.executor.ResponseInstruction;
+import org.springframework.webflow.test.MockExternalContext;
+
+/**
+ * Test case that looks for the miminum conversation size.
+ * 
+ * @author Erwin Vervaet
+ */
+public class ConversationSizeTests extends TestCase {
+	
+	private FlowExecutor flowExecutor; 
+
+	protected void setUp() throws Exception {
+		AbstractFlowBuilderFlowRegistryFactoryBean flowRegistryFactory =
+			new SizeTestFlowRegistry();
+		flowRegistryFactory.setBeanFactory(new StaticListableBeanFactory());
+		flowRegistryFactory.afterPropertiesSet();
+		FlowDefinitionRegistry flowRegistry = flowRegistryFactory.getRegistry();
+		
+		FlowExecutorFactoryBean flowExecutorFactory = new FlowExecutorFactoryBean();
+		flowExecutorFactory.setDefinitionLocator(flowRegistry);
+		flowExecutorFactory.setRepositoryType(RepositoryType.CONTINUATION);
+		flowExecutorFactory.afterPropertiesSet();
+		flowExecutor = flowExecutorFactory.getFlowExecutor();
+	}
+	
+	public void testConversationSize() throws Exception {
+		MockExternalContext context = new MockExternalContext();
+		SharedAttributeMap session = context.getSessionMap();
+		
+		// initially the session is empty
+		assertTrue(session.isEmpty());
+		
+		ResponseInstruction ri = flowExecutor.launch("size-test-flow", context);
+		assertTrue(ri.getFlowExecutionContext().isActive());
+		assertTrue(ri.getViewSelection() instanceof FlowExecutionRedirect); // alwaysRedirectOnPause
+		
+		// the launch has stored a ConversationContainer in the session since we're using
+		// SessionBindingConversationManager (the default)
+		assertEquals(1, session.size());
+		ConversationContainer conversationContainer = (ConversationContainer)session.get(
+				SessionBindingConversationManager.CONVERSATION_CONTAINER_KEY);
+		assertNotNull(conversationContainer);
+		assertEquals(1, conversationContainer.size());
+		int initialSize = getSerializedSize(conversationContainer);
+		
+		ri = flowExecutor.refresh(ri.getFlowExecutionKey(), context);
+		assertTrue(ri.getFlowExecutionContext().isActive());
+		assertEquals("view", ((ApplicationView)ri.getViewSelection()).getViewName());
+		
+		// the refresh did not impact the size of the session
+		assertEquals(1, session.size());
+		assertSame(conversationContainer, session.get(SessionBindingConversationManager.CONVERSATION_CONTAINER_KEY));
+		assertEquals(1, conversationContainer.size());
+		
+		ri = flowExecutor.resume(ri.getFlowExecutionKey(), "end", context);
+		assertFalse(ri.getFlowExecutionContext().isActive());
+		assertTrue(ri.isNull());
+		
+		// the conversation ended but the ConversationContainer is still in the session
+		assertEquals(1, session.size());
+		assertSame(conversationContainer, session.get(SessionBindingConversationManager.CONVERSATION_CONTAINER_KEY));
+		assertEquals(0, conversationContainer.size());
+		int inactiveSize = getSerializedSize(conversationContainer);
+		
+		assertTrue(inactiveSize < initialSize);
+	}
+	
+	// helpers
+	
+	private int getSerializedSize(Object obj) throws Exception {
+		ByteArrayOutputStream bout = new ByteArrayOutputStream();
+		ObjectOutputStream oout = new ObjectOutputStream(bout);
+		oout.writeObject(obj);
+		oout.flush();
+		int objSize = bout.toByteArray().length;
+		
+		System.out.println(">>>> serialized size of '" + obj + "' is " + objSize);
+		
+		return objSize;
+	}
+	
+	private static class SizeTestFlowBuilder extends AbstractFlowBuilder {
+		public void buildStates() throws FlowBuilderException {
+			addViewState("view", "view", transition(on("end"), to("end")));
+			addEndState("end");
+		}
+	}
+	
+	private static class SizeTestFlowRegistry extends AbstractFlowBuilderFlowRegistryFactoryBean {
+		protected void doPopulate(FlowDefinitionRegistry registry) {
+			registerFlowDefinition(registry, "size-test-flow", new SizeTestFlowBuilder());
+		}
+	}
+}