SWF-1114 - Consider making ViewActionStateHolder and ViewRootHolder put in flash scope Serializable

spring-webflow/src/main/java/org/springframework/webflow/engine/support/ActionExecutingViewFactory.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.webflow.engine.support;
 
+import java.io.Serializable;
+
 import org.springframework.web.util.WebUtils;
 import org.springframework.webflow.execution.Action;
 import org.springframework.webflow.execution.ActionExecutor;
@@ -79,7 +81,7 @@ public class ActionExecutingViewFactory implements ViewFactory {
 			userEventProcessed = true;
 		}
 
-		public Object getUserEventState() {
+		public Serializable getUserEventState() {
 			return null;
 		}
 

spring-webflow/src/main/java/org/springframework/webflow/execution/View.java

@@ -16,6 +16,7 @@
 package org.springframework.webflow.execution;
 
 import java.io.IOException;
+import java.io.Serializable;
 
 import org.springframework.webflow.engine.ViewState;
 
@@ -24,6 +25,7 @@ import org.springframework.webflow.engine.ViewState;
  * and handle the resulting event once the client responds.
  * 
  * @author Keith Donald
+ * @author Jeremy Grelle
  * @see ViewFactory
  */
 public interface View {
@@ -74,10 +76,10 @@ public interface View {
 	/**
 	 * A memento holding the results of processing a user event. Used to allow transient view state such as binding and
 	 * validation errors to survive a flow execution redirect.
-	 * @return the user event state object, or null if no event state needs managing
+	 * @return the serializable user event state object, or null if no event state needs managing
 	 * @see #processUserEvent()
 	 */
-	public Object getUserEventState();
+	public Serializable getUserEventState();
 
 	/**
 	 * Saves any state associated with this view out to view scope. Called when exiting a {@link ViewState} to allow for

spring-webflow/src/main/java/org/springframework/webflow/mvc/view/AbstractMvcView.java

@@ -16,6 +16,7 @@
 package org.springframework.webflow.mvc.view;
 
 import java.io.IOException;
+import java.io.Serializable;
 import java.lang.reflect.Array;
 import java.util.HashMap;
 import java.util.Iterator;
@@ -224,7 +225,7 @@ public abstract class AbstractMvcView implements View {
 		userEventProcessed = true;
 	}
 
-	public Object getUserEventState() {
+	public Serializable getUserEventState() {
 		return new ViewActionStateHolder(eventId, userEventProcessed, mappingResults);
 	}
 

spring-webflow/src/main/java/org/springframework/webflow/mvc/view/ViewActionStateHolder.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.webflow.mvc.view;
 
+import java.io.Serializable;
+
 import org.springframework.binding.mapping.MappingResults;
 import org.springframework.core.style.ToStringCreator;
 
@@ -23,7 +25,7 @@ import org.springframework.core.style.ToStringCreator;
  * 
  * @author Scott Andrews
  */
-public class ViewActionStateHolder {
+public class ViewActionStateHolder implements Serializable {
 
 	public static final String KEY = "webflowViewActionStateHolder";
 
@@ -31,7 +33,7 @@ public class ViewActionStateHolder {
 
 	private boolean userEventProcessed;
 
-	private MappingResults mappingResults;
+	private transient MappingResults mappingResults;
 
 	public ViewActionStateHolder(String eventId, boolean userEventProcessed, MappingResults mappingResults) {
 		this.eventId = eventId;

spring-webflow/src/main/java/org/springframework/webflow/test/MockViewFactoryCreator.java

@@ -16,6 +16,7 @@
 package org.springframework.webflow.test;
 
 import java.io.IOException;
+import java.io.Serializable;
 
 import org.springframework.binding.convert.ConversionService;
 import org.springframework.binding.expression.Expression;
@@ -107,7 +108,7 @@ class MockViewFactoryCreator implements ViewFactoryCreator {
 			// TODO - implement me as appropriate for a test environment
 		}
 
-		public Object getUserEventState() {
+		public Serializable getUserEventState() {
 			return null;
 		}
 

spring-webflow/src/test/java/org/springframework/webflow/engine/StubViewFactory.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.webflow.engine;
 
+import java.io.Serializable;
+
 import org.springframework.webflow.execution.Event;
 import org.springframework.webflow.execution.RequestContext;
 import org.springframework.webflow.execution.View;
@@ -22,7 +24,8 @@ import org.springframework.webflow.execution.ViewFactory;
 
 public class StubViewFactory implements ViewFactory {
 
-	public static Object USER_EVENT_STATE = new Object();
+	public static Serializable USER_EVENT_STATE = new Serializable() {
+	};
 
 	public View getView(RequestContext context) {
 		return new NullView(context);
@@ -47,7 +50,7 @@ public class StubViewFactory implements ViewFactory {
 
 		}
 
-		public Object getUserEventState() {
+		public Serializable getUserEventState() {
 			return USER_EVENT_STATE;
 		}
 

spring-webflow/src/test/java/org/springframework/webflow/mvc/view/MvcViewTests.java

@@ -1,6 +1,12 @@
 package org.springframework.webflow.mvc.view;
 
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
 import java.security.Principal;
+import java.text.SimpleDateFormat;
 import java.util.Calendar;
 import java.util.Date;
 import java.util.List;
@@ -289,6 +295,79 @@ public class MvcViewTests extends TestCase {
 		assertEquals("bogus 2", bm.getFieldValue("dateProperty"));
 	}
 
+	public void testResumeEventBindingErrorsRedirectToReplicatedSessionAfterPost() throws Exception {
+		MockRequestControlContext context = new MockRequestControlContext();
+		context.putRequestParameter("_eventId", "submit");
+		context.putRequestParameter("integerProperty", "bogus 1");
+		context.putRequestParameter("dateProperty", "bogus 2");
+		BindBean bindBean = new BindBean();
+		StaticExpression modelObject = new StaticExpression(bindBean);
+		modelObject.setExpressionString("bindBean");
+		context.getCurrentState().getAttributes().put("model", modelObject);
+		context.getFlowScope().put("bindBean", bindBean);
+		context.getMockExternalContext().setNativeContext(new MockServletContext());
+		context.getMockExternalContext().setNativeRequest(new MockHttpServletRequest());
+		context.getMockExternalContext().setNativeResponse(new MockHttpServletResponse());
+		context.getMockFlowExecutionContext().setKey(new MockFlowExecutionKey("c1v1"));
+		org.springframework.web.servlet.View mvcView = new MockView();
+		AbstractMvcView view = new MockMvcView(mvcView, context);
+		view.setExpressionParser(DefaultExpressionParserFactory.getExpressionParser());
+		view.setMessageCodesResolver(new WebFlowMessageCodesResolver());
+		context.setAlwaysRedirectOnPause(true);
+		assertTrue(view.userEventQueued());
+		view.processUserEvent();
+		assertFalse(view.userEventQueued());
+		assertFalse(view.hasFlowEvent());
+		Object viewActionState = view.getUserEventState();
+		assertNotNull(viewActionState);
+
+		viewActionState = saveAndRestoreViewActionState(viewActionState);
+
+		MockRequestControlContext context2 = new MockRequestControlContext();
+		context2.getFlashScope().put(org.springframework.webflow.execution.View.USER_EVENT_STATE_ATTRIBUTE,
+				viewActionState);
+		BindBean bindBean2 = new BindBean();
+		StaticExpression modelObject2 = new StaticExpression(bindBean2);
+		modelObject2.setExpressionString("bindBean");
+		context2.getCurrentState().getAttributes().put("model", modelObject);
+		context2.getFlowScope().put("bindBean", bindBean);
+		context2.getMockExternalContext().setNativeContext(new MockServletContext());
+		context2.getMockExternalContext().setNativeRequest(new MockHttpServletRequest());
+		context2.getMockExternalContext().setNativeResponse(new MockHttpServletResponse());
+		context2.getMockFlowExecutionContext().setKey(new MockFlowExecutionKey("c1v1"));
+		AbstractMvcView view2 = new MockMvcView(mvcView, context2);
+		view2.setExpressionParser(DefaultExpressionParserFactory.getExpressionParser());
+		view2.setMessageCodesResolver(new WebFlowMessageCodesResolver());
+		view2.restoreState((ViewActionStateHolder) viewActionState);
+		assertFalse(view2.userEventQueued());
+		view2.render();
+		assertEquals(context2.getFlowScope().get("bindBean"), model.get("bindBean"));
+		BindingModel bm = (BindingModel) model.get(BindingResult.MODEL_KEY_PREFIX + "bindBean");
+		assertNotNull(bm);
+		assertEquals(new Integer(3), bm.getFieldValue("integerProperty"));
+		assertEquals(new SimpleDateFormat("MM-dd-yyyy").parse("01-01-2008"), bm.getFieldValue("dateProperty"));
+	}
+
+	private Object saveAndRestoreViewActionState(Object viewActionState) throws Exception {
+		File tempFile = new File("serializable.tmp");
+
+		FileOutputStream fos = new FileOutputStream(tempFile);
+		ObjectOutputStream objOut = new ObjectOutputStream(fos);
+		objOut.writeObject(viewActionState);
+		objOut.close();
+
+		FileInputStream fis = new FileInputStream(tempFile);
+		ObjectInputStream objIn = new ObjectInputStream(fis);
+		Object restoredState = objIn.readObject();
+		objIn.close();
+
+		tempFile.delete();
+
+		assertNotSame(viewActionState, restoredState);
+
+		return restoredState;
+	}
+
 	public void testResumeEventModelBindingAllowedFields() throws Exception {
 		MockRequestContext context = new MockRequestContext();
 		context.putRequestParameter("_eventId", "submit");