Fix issue w/ use of UrlPathHelper's urlDecode property

Before this change the getPathWithinServletMapping method of
UrlPathHelper could not work properly when a default servlet mapping
(i.e. "/") was used in combination with urlDecode=false. The fact that
the getServletPath() method of HttpServletRequest always returns a
decoded path was getting in the way.

Although there is no way to check Servlet mappings through the Servlet
API, this change aims to detect the given scenario and returns the full
path following the context path thus avoiding URL decoding.

Note that the same can be achieved by setting urlDecode=false and
alwaysUseFullPath=true. However this change ensures that urlDecode
works properly without having to know that.

Issue: SPR-11101

spring-web/src/main/java/org/springframework/web/util/UrlPathHelper.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2014 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.
@@ -181,11 +181,24 @@ public class UrlPathHelper {
 		}
 		else {
 			// Special case: URI is different from servlet path.
-			// Can happen e.g. with index page: URI="/", servletPath="/index.html"
-			// Use path info if available, as it indicates an index page within
-			// a servlet mapping. Otherwise, use the full servlet path.
 			String pathInfo = request.getPathInfo();
-			return (pathInfo != null ? pathInfo : servletPath);
+			if (pathInfo != null) {
+				// Use path info if available. Indicates index page within a servlet mapping?
+				// e.g. with index page: URI="/", servletPath="/index.html"
+				return pathInfo;
+			}
+			if (this.urlDecode == false) {
+				// No path info... (not mapped by prefix, nor by extension, nor "/*")
+				// For the default servlet mapping (i.e. "/"), urlDecode=false can
+				// cause issues since getServletPath() returns a decoded path.
+				// If decoding pathWithinApp yields a match just use pathWithinApp
+				path = getRemainingPath(decodeInternal(request, pathWithinApp), servletPath, false);
+				if (path != null) {
+					return pathWithinApp;
+				}
+			}
+			// Otherwise, use the full servlet path
+			return servletPath;
 		}
 	}
 

spring-web/src/test/java/org/springframework/web/util/UrlPathHelperTests.java

@@ -77,6 +77,20 @@ public class UrlPathHelperTests {
 		assertEquals("Incorrect path returned", "/welcome.html", helper.getPathWithinServletMapping(request));
 	}
 
+	// SPR-11101
+
+	@Test
+	public void getPathWithinServletWithoutUrlDecoding() {
+		request.setContextPath("/SPR-11101");
+		request.setServletPath("/test_url_decoding/a/b");
+		request.setRequestURI("/test_url_decoding/a%2Fb");
+
+		helper.setUrlDecode(false);
+		String actual = helper.getPathWithinServletMapping(request);
+
+		assertEquals("/test_url_decoding/a%2Fb", actual);
+	}
+
 	@Test
 	public void getRequestUri() {
 		request.setRequestURI("/welcome.html");