From ca3ac7a0b9a4e99482e0dd6b5fea01d6d8bb5f12 Mon Sep 17 00:00:00 2001
From: Keith Donald <kdonald@vmware.com>
Date: Thu, 5 Apr 2007 19:16:55 +0000
Subject: [PATCH] delegating should proceed to next resolver if no execution
 bound

---
 .../jsf/DelegatingFlowVariableResolver.java   | 28 ++++++++--------
 .../jsf/FlowExecutionHolderUtils.java         | 32 +++++++++++++------
 2 files changed, 37 insertions(+), 23 deletions(-)

diff --git a/spring-webflow/src/main/java/org/springframework/webflow/executor/jsf/DelegatingFlowVariableResolver.java b/spring-webflow/src/main/java/org/springframework/webflow/executor/jsf/DelegatingFlowVariableResolver.java
index ab029256..8b7359f6 100644
--- a/spring-webflow/src/main/java/org/springframework/webflow/executor/jsf/DelegatingFlowVariableResolver.java
+++ b/spring-webflow/src/main/java/org/springframework/webflow/executor/jsf/DelegatingFlowVariableResolver.java
@@ -66,20 +66,20 @@ public class DelegatingFlowVariableResolver extends VariableResolver {
 	 * chain.
 	 */
 	public Object resolveVariable(FacesContext context, String name) throws EvaluationException {
-		FlowExecution execution = FlowExecutionHolderUtils.getRequiredCurrentFlowExecution(context);
-		// try flash/flow/conversation
-		if (execution.getActiveSession().getFlashMap().contains(name)) {
-			return execution.getActiveSession().getFlashMap().get(name);
-		}
-		else if (execution.getActiveSession().getScope().contains(name)) {
-			return execution.getActiveSession().getScope().get(name);
-		}
-		else if (execution.getConversationScope().contains(name)) {
-			return execution.getConversationScope().get(name);
-		}
-		else {
-			// neither found a value, delegate to next resolver in the chain
-			return resolverDelegate.resolveVariable(context, name);
+		FlowExecution execution = FlowExecutionHolderUtils.getCurrentFlowExecution(context);
+		if (execution != null) {
+			// try flash/flow/conversation
+			if (execution.getActiveSession().getFlashMap().contains(name)) {
+				return execution.getActiveSession().getFlashMap().get(name);
+			}
+			else if (execution.getActiveSession().getScope().contains(name)) {
+				return execution.getActiveSession().getScope().get(name);
+			}
+			else if (execution.getConversationScope().contains(name)) {
+				return execution.getConversationScope().get(name);
+			}
 		}
+		// no flow execution bound or flow execution attribute found with that name - delegate
+		return resolverDelegate.resolveVariable(context, name);
 	}
 }
\ No newline at end of file
diff --git a/spring-webflow/src/main/java/org/springframework/webflow/executor/jsf/FlowExecutionHolderUtils.java b/spring-webflow/src/main/java/org/springframework/webflow/executor/jsf/FlowExecutionHolderUtils.java
index 33ed8bcf..77772f81 100644
--- a/spring-webflow/src/main/java/org/springframework/webflow/executor/jsf/FlowExecutionHolderUtils.java
+++ b/spring-webflow/src/main/java/org/springframework/webflow/executor/jsf/FlowExecutionHolderUtils.java
@@ -60,24 +60,38 @@ public class FlowExecutionHolderUtils {
 	}
 
 	/**
-	 * Returns the current flow execution holder for the given faces context.
+	 * Returns the current flow execution in the given faces context.
 	 * @param context faces context
-	 * @return the flow execution holder or <code>null</code> if none set
-	 * @throws EvaluationException if no flow execution was bound
+	 * @return the flow execution or <code>null</code> if no execution is bound
 	 */
-	public static FlowExecution getRequiredCurrentFlowExecution(FacesContext context) throws EvaluationException {
+	public static FlowExecution getCurrentFlowExecution(FacesContext context) {
 		FlowExecutionHolder holder = getFlowExecutionHolder(context);
 		if (holder != null) {
 			return holder.getFlowExecution();
-		}
-		else {
-			throw new EvaluationException(
-					"FlowExecution is not bound to current thread context - has the flow ended or expired?");
+		} else {
+			return null;
 		}
 	}
 	
+	/**
+	 * Returns the current required flow execution in the given faces context.
+	 * @param context faces context
+	 * @return the flow execution
+	 * @throws EvaluationException if no flow execution was bound
+	 */
+	public static FlowExecution getRequiredCurrentFlowExecution(FacesContext context) throws EvaluationException {
+		FlowExecution execution = getCurrentFlowExecution(context);
+		if (execution != null) {
+			return execution;
+		}
+		else {
+			throw new EvaluationException("No current FlowExecution bound to the Faces Context "
+					+ "- was the current flow execution restored before any components referenced it? "
+					+ "Has the flow execution ended or expired?");
+		}
+	}
+
 	private static String getFlowExecutionHolderKey() {
 		return FlowExecutionHolder.class.getName();
 	}
-
 }
\ No newline at end of file