#22

spring-mvc-cache-control/src/main/java/net/rossillo/spring/web/mvc/CacheControl.java

@@ -36,4 +36,9 @@
 	 */
 	int sharedMaxAge() default -1;
 
+	/**
+	 * Sometimes caching need vary headers. E.g. 'Accept'.
+	 */
+	String[] vary() default {};
+
 }

spring-mvc-cache-control/src/main/java/net/rossillo/spring/web/mvc/CacheControlHandlerInterceptor.java

@@ -14,54 +14,59 @@
 /**
  * Provides a cache control handler interceptor to assign cache-control
  * headers to HTTP responses.
- * 
+ *
  * @author Scott Rossillo
  *
  */
 public class CacheControlHandlerInterceptor extends HandlerInterceptorAdapter implements HandlerInterceptor {
 
 	private static final String HEADER_EXPIRES = "Expires";
 	private static final String HEADER_CACHE_CONTROL = "Cache-Control";
-
+	private static final String HEADER_VARY = "Vary";
+
 	private boolean useExpiresHeader = true;
-	
+
 	/**
 	 * Creates a new cache control handler interceptor.
 	 */
 	public CacheControlHandlerInterceptor() {
 		super();
 	}
-	
+
 	/**
 	 * Assigns a <code>CacheControl</code> header to the given <code>response</code>.
-	 * 
+	 *
 	 * @param request the <code>HttpServletRequest</code>
 	 * @param response the <code>HttpServletResponse</code>
 	 * @param handler the handler for the given <code>request</code>
 	 */
 	protected final void assignCacheControlHeader(
 			final HttpServletRequest request,
-			final HttpServletResponse response, 
+			final HttpServletResponse response,
 			final Object handler) {
-		
+
 		final CacheControl cacheControl = this.getCacheControl(request, response, handler);
 		final String cacheControlHeader = this.createCacheControlHeader(cacheControl);
-		
+
 		if (cacheControlHeader != null) {
 			response.setHeader(HEADER_CACHE_CONTROL, cacheControlHeader);
 			if (useExpiresHeader) {
 				response.setDateHeader(HEADER_EXPIRES, createExpiresHeader(cacheControl));
 			}
+			String[] vary = cacheControl.vary();
+			for (String v : vary) {
+				response.addHeader(HEADER_VARY, v);
+			}
 		}
 	}
-	
+
 	/**
 	 * Returns cache control header value from the given {@link CacheControl}
 	 * annotation.
-	 * 
+	 *
 	 * @param cacheControl the <code>CacheControl</code> annotation from which to
 	 * create the returned cache control header value
-	 * 
+	 *
 	 * @return the cache control header value
 	 */
 	protected final String createCacheControlHeader(final CacheControl cacheControl) {
@@ -96,77 +101,77 @@ protected final String createCacheControlHeader(final CacheControl cacheControl)
 
 		return (builder.length() > 0 ? builder.toString() : null);
 	}
-	
+
 	/**
-	 * Returns an expires header value generated from the given 
+	 * Returns an expires header value generated from the given
 	 * {@link CacheControl} annotation.
-	 * 
+	 *
 	 * @param cacheControl the <code>CacheControl</code> annotation from which to
 	 * create the returned expires header value
-	 * 
+	 *
 	 * @return the expires header value
 	 */
 	protected final long createExpiresHeader(final CacheControl cacheControl) {
-		
+
 		final Calendar expires = new GregorianCalendar(TimeZone.getTimeZone("GMT"));
-		
+
 		if (cacheControl.maxAge() >= 0) {
 			expires.add(Calendar.SECOND, cacheControl.maxAge());
 		}
-		
+
 		return expires.getTime().getTime();
 	}
-	
+
 	/**
 	 * Returns the {@link CacheControl} annotation specified for the
 	 * given request, response and handler.
-	 * 
+	 *
 	 * @param request the current <code>HttpServletRequest</code>
 	 * @param response the current <code>HttpServletResponse</code>
 	 * @param handler the current request handler
-	 * 
+	 *
 	 * @return the <code>CacheControl</code> annotation specified by
 	 * the given <code>handler</code> if present; <code>null</code> otherwise
 	 */
 	protected final CacheControl getCacheControl(
 			final HttpServletRequest request,
-			final HttpServletResponse response, 
+			final HttpServletResponse response,
 			final Object handler) {
-		
+
 		if (handler == null || !(handler instanceof HandlerMethod)) {
 			return null;
 		}
-		
+
 		final HandlerMethod handlerMethod = (HandlerMethod) handler;
 		CacheControl cacheControl = handlerMethod.getMethodAnnotation(CacheControl.class);
-		
+
 		if (cacheControl == null) {
 			return handlerMethod.getBeanType().getAnnotation(CacheControl.class);
 		}
-		
+
 		return cacheControl;
 	}
-	
+
 	@Override
 	public final boolean preHandle(
 			final HttpServletRequest request,
-			final HttpServletResponse response, 
+			final HttpServletResponse response,
 			final Object handler) throws Exception {
-		
+
 		this.assignCacheControlHeader(request, response, handler);
-		
+
 		return super.preHandle(request, response, handler);
 	}
 
 	/**
 	 * True to set an expires header when a {@link CacheControl} annotation is present
 	 * on a handler; false otherwise.   Defaults to true.
-	 * 
-	 * @param useExpiresHeader <code>true</code> to set an expires header when a 
+	 *
+	 * @param useExpiresHeader <code>true</code> to set an expires header when a
 	 * <code>CacheControl</code> annotation is present on a handler; <code>false</code> otherwise
 	 */
 	public final void setUseExpiresHeader(final boolean useExpiresHeader) {
 		this.useExpiresHeader = useExpiresHeader;
 	}
-	
+
 }

spring-mvc-cache-control/src/test/java/net/rossillo/spring/web/mvc/CacheControlAnnotatedTestController.java

@@ -25,6 +25,11 @@ public String handlePubliclyCachedPageAndProxyRevalidatedRequest() {
 	public String handlePrivatelyCachedPageRequest() {
 		return null;
 	}
+
+	@CacheControl(policy = CachePolicy.PRIVATE, maxAge = 360, vary = "Accept")
+	public String handlePrivatelyCachedPageRequestWithVary() {
+		return null;
+	}
 
 	public String handleWithDefaultPolicy() {
 		return null;

spring-mvc-cache-control/src/test/java/net/rossillo/spring/web/mvc/CacheControlHandlerInterceptorTest.java

@@ -97,7 +97,25 @@ public void testCacheControlPrivate() throws Exception {
 		assertTrue(response.getHeader("Cache-Control").contains("private"));
 		assertFalse(response.getHeader("Cache-Control").contains("public"));
 	}
-
+
+	@Test
+	public void testCacheControlPrivateWithVary() throws Exception {
+
+		final HandlerMethod handler = new HandlerMethod(
+				controller,
+				controller.getClass().getMethod("handlePrivatelyCachedPageRequestWithVary"));
+
+		interceptor.preHandle(request, response, handler);
+
+		System.err.println("Vary: " + response.getHeader("Vary"));
+
+		assertNotNull(response.getHeader("Cache-Control"));
+		assertTrue(response.getHeader("Cache-Control").contains("private"));
+		assertFalse(response.getHeader("Cache-Control").contains("public"));
+		assertTrue(response.getHeader("Vary").contains("Accept"));
+
+	}
+
 	@Test
 	public void testExpires() throws Exception {