XML configuration support for RFC 5861

This commit adds the XML+XSD configuration part of the RFC 5861
Cache-Control directives added in Spring's `CacheControl`.

Issue: SPR-13841

spring-web/src/main/java/org/springframework/http/CacheControl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -212,34 +212,34 @@ public class CacheControl {
 	}
 
 	/**
-     * Add an "stale-while-revalidate" directive.
-     * <p>This directive indicates that caches MAY serve the response in
-     * which it appears after it becomes stale, up to the indicated number of seconds.
-     * If a cached response is served stale due to the presence of this extension,
-     * the cache SHOULD attempt to revalidate it while still serving stale responses (i.e., without blocking).
-     * @param staleWhileRevalidate the maximum time the response should be used while being revalidated
-     * @param unit the time unit of the {@code sMaxAge} argument
-     * @return {@code this}, to facilitate method chaining
-     * @see <a href="http://tools.ietf.org/html/rfc5861#section-3">rfc5861 section 3</a>
-     */
-    public CacheControl staleWhileRevalidate(long staleWhileRevalidate, TimeUnit unit) {
-    	this.staleWhileRevalidate = unit.toSeconds(staleWhileRevalidate);
-        return this;
-    }
-
-    /**
-     * Add an "stale-if-error" directive.
-     * <p>This directive indicates that that when an error is encountered, a cached stale response MAY be used to satisfy
-     * the request, regardless of other freshness information..
-     * @param staleIfError the maximum time the response should be used when errors are encountered
-     * @param unit the time unit of the {@code sMaxAge} argument
-     * @return {@code this}, to facilitate method chaining
-     * @see <a href="http://tools.ietf.org/html/rfc5861#section-4">rfc5861 section 4</a>
-     */
-    public CacheControl staleIfError(long staleIfError, TimeUnit unit) {
-        this.staleIfError = unit.toSeconds(staleIfError);
-        return this;
-    }
+	 * Add a "stale-while-revalidate" directive.
+	 * <p>This directive indicates that caches MAY serve the response in
+	 * which it appears after it becomes stale, up to the indicated number of seconds.
+	 * If a cached response is served stale due to the presence of this extension,
+	 * the cache SHOULD attempt to revalidate it while still serving stale responses (i.e., without blocking).
+	 * @param staleWhileRevalidate the maximum time the response should be used while being revalidated
+	 * @param unit the time unit of the {@code staleWhileRevalidate} argument
+	 * @return {@code this}, to facilitate method chaining
+	 * @see <a href="https://tools.ietf.org/html/rfc5861#section-3">rfc5861 section 3</a>
+	 */
+	public CacheControl staleWhileRevalidate(long staleWhileRevalidate, TimeUnit unit) {
+		this.staleWhileRevalidate = unit.toSeconds(staleWhileRevalidate);
+		return this;
+	}
+
+	/**
+	 * Add a "stale-if-error" directive.
+	 * <p>This directive indicates that when an error is encountered, a cached stale response MAY be used to satisfy
+	 * the request, regardless of other freshness information.
+	 * @param staleIfError the maximum time the response should be used when errors are encountered
+	 * @param unit the time unit of the {@code staleIfError} argument
+	 * @return {@code this}, to facilitate method chaining
+	 * @see <a href="https://tools.ietf.org/html/rfc5861#section-4">rfc5861 section 4</a>
+	 */
+	public CacheControl staleIfError(long staleIfError, TimeUnit unit) {
+		this.staleIfError = unit.toSeconds(staleIfError);
+		return this;
+	}
 
 
 	/**
@@ -275,10 +275,10 @@ public class CacheControl {
 		if (this.sMaxAge != -1) {
 			appendDirective(ccValue, "s-maxage=" + Long.toString(this.sMaxAge));
 		}
-		if(this.staleIfError != -1) {
+		if (this.staleIfError != -1) {
 			appendDirective(ccValue, "stale-if-error=" + Long.toString(this.staleIfError));
 		}
-		if(this.staleWhileRevalidate != -1) {
+		if (this.staleWhileRevalidate != -1) {
 			appendDirective(ccValue, "stale-while-revalidate=" + Long.toString(this.staleWhileRevalidate));
 		}
 

spring-web/src/test/java/org/springframework/http/CacheControlTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.

spring-webmvc/src/main/java/org/springframework/web/servlet/config/ResourcesBeanDefinitionParser.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -242,6 +242,14 @@ class ResourcesBeanDefinitionParser implements BeanDefinitionParser {
 		if (element.hasAttribute("s-maxage")) {
 			cacheControl = cacheControl.sMaxAge(Long.parseLong(element.getAttribute("s-maxage")), TimeUnit.SECONDS);
 		}
+		if (element.hasAttribute("stale-while-revalidate")) {
+			cacheControl = cacheControl.staleWhileRevalidate(
+					Long.parseLong(element.getAttribute("stale-while-revalidate")), TimeUnit.SECONDS);
+		}
+		if (element.hasAttribute("stale-if-error")) {
+			cacheControl = cacheControl.staleIfError(
+					Long.parseLong(element.getAttribute("stale-if-error")), TimeUnit.SECONDS);
+		}
 		return cacheControl;
 	}
 

spring-webmvc/src/main/resources/org/springframework/web/servlet/config/spring-mvc-4.3.xsd

@@ -581,6 +581,22 @@
 			<xsd:annotation>
 				<xsd:documentation><![CDATA[
 	Adds a "s-maxage" directive in the Cache-Control header.
+	This directive has the same meaning as the "max-age" directive, except it only applies to shared caches.
+					]]></xsd:documentation>
+			</xsd:annotation>
+		</xsd:attribute>
+		<xsd:attribute name="stale-while-revalidate" type="xsd:int" use="optional">
+			<xsd:annotation>
+				<xsd:documentation><![CDATA[
+	Adds a "stale-while-revalidate" directive in the Cache-Control header.
+	This indicates that caches may serve the response after it becomes stale up to the given number of seconds.
+					]]></xsd:documentation>
+			</xsd:annotation>
+		</xsd:attribute>
+		<xsd:attribute name="stale-if-error" type="xsd:int" use="optional">
+			<xsd:annotation>
+				<xsd:documentation><![CDATA[
+	Adds a "s-maxage" directive in the Cache-Control header.
 	This directive has the same meaning as the "max-age" directive, except it only applies to shared caches.
 					]]></xsd:documentation>
 			</xsd:annotation>