From cc3239987853251f825054f5da97fd24630911a0 Mon Sep 17 00:00:00 2001
From: Arjen Poutsma <apoutsma@vmware.com>
Date: Mon, 30 Nov 2009 10:29:27 +0000
Subject: [PATCH] SPR-6470 - Make filterModel() in MappingJacksonJsonView more
 lenient

---
 .../servlet/view/json/MappingJacksonJsonView.java    | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/view/json/MappingJacksonJsonView.java b/org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/view/json/MappingJacksonJsonView.java
index 69f2e75697b..d1e778aadff 100644
--- a/org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/view/json/MappingJacksonJsonView.java
+++ b/org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/view/json/MappingJacksonJsonView.java
@@ -119,22 +119,26 @@ public class MappingJacksonJsonView extends AbstractView {
 	protected void renderMergedOutputModel(Map<String, Object> model,
 			HttpServletRequest request,
 			HttpServletResponse response) throws Exception {
-		model = filterModel(model);
+		Object value = filterModel(model);
 		JsonGenerator generator =
 				objectMapper.getJsonFactory().createJsonGenerator(response.getOutputStream(), encoding);
 		if (prefixJson) {
 			generator.writeRaw("{} && ");
 		}
-		objectMapper.writeValue(generator, model);
+		objectMapper.writeValue(generator, value);
 	}
 
 	/**
-	 * Filters out undesired attributes from the given model.
+	 * Filters out undesired attributes from the given model. The return value can be either another {@link Map}, or a
+	 * single value object.
 	 *
 	 * <p>Default implementation removes {@link BindingResult} instances and entries not included in the {@link
 	 * #setRenderedAttributes(Set) renderedAttributes} property.
+	 *
+	 * @param model the model, as passed on to {@link #renderMergedOutputModel}
+	 * @return the object to be rendered
 	 */
-	protected Map<String, Object> filterModel(Map<String, Object> model) {
+	protected Object filterModel(Map<String, Object> model) {
 		Map<String, Object> result = new HashMap<String, Object>(model.size());
 		Set<String> renderedAttributes =
 				!CollectionUtils.isEmpty(this.renderedAttributes) ? this.renderedAttributes : model.keySet();