This will also transparently set the appropriate response headers, - * for both the modified case and the not-modified case. + *
This will also transparently set the "Last-Modified" response header + * and HTTP status when applicable. *
Typical usage: *
* public String myHandleMethod(WebRequest webRequest, Model model) {
@@ -142,6 +142,8 @@ public interface WebRequest extends RequestAttributes {
* model.addAttribute(...);
* return "myViewName";
* }
+ * This method works with conditional GET/HEAD requests, but + * also with conditional POST/PUT/DELETE requests. *
Note: you can use either * this {@code #checkNotModified(long)} method; or * {@link #checkNotModified(String)}. If you want enforce both @@ -160,10 +162,10 @@ public interface WebRequest extends RequestAttributes { boolean checkNotModified(long lastModifiedTimestamp); /** - * Check whether the request qualifies as not modified given the + * Check whether the requested resource has been modified given the * supplied {@code ETag} (entity tag), as determined by the application. - *
This will also transparently set the appropriate response headers, - * for both the modified case and the not-modified case. + *
This will also transparently set the "ETag" response header + * and HTTP status when applicable. *
Typical usage: *
* public String myHandleMethod(WebRequest webRequest, Model model) {
@@ -185,18 +187,16 @@ public interface WebRequest extends RequestAttributes {
* @param etag the entity tag that the application determined
* for the underlying resource. This parameter will be padded
* with quotes (") if necessary.
- * @return whether the request qualifies as not modified,
- * allowing to abort request processing and relying on the response
- * telling the client that the content has not been modified
+ * @return true if the request does not require further processing.
*/
boolean checkNotModified(String etag);
/**
- * Check whether the request qualifies as not modified given the
+ * Check whether the requested resource has been modified given the
* supplied {@code ETag} (entity tag) and last-modified timestamp,
* as determined by the application.
* This will also transparently set the "ETag" and "Last-Modified"
- * response headers, for both the modified case and the not-modified case.
+ * response headers, and HTTP status when applicable.
*
Typical usage:
*
* public String myHandleMethod(WebRequest webRequest, Model model) {
@@ -210,6 +210,8 @@ public interface WebRequest extends RequestAttributes {
* model.addAttribute(...);
* return "myViewName";
* }
+ * This method works with conditional GET/HEAD requests, but
+ * also with conditional POST/PUT/DELETE requests.
*
Note: The HTTP specification recommends
* setting both ETag and Last-Modified values, but you can also
* use {@code #checkNotModified(String)} or
@@ -219,9 +221,7 @@ public interface WebRequest extends RequestAttributes {
* with quotes (") if necessary.
* @param lastModifiedTimestamp the last-modified timestamp that
* the application determined for the underlying resource
- * @return whether the request qualifies as not modified,
- * allowing to abort request processing and relying on the response
- * telling the client that the content has not been modified
+ * @return true if the request does not require further processing.
* @since 4.2
*/
boolean checkNotModified(String etag, long lastModifiedTimestamp);
diff --git a/spring-web/src/test/java/org/springframework/web/context/request/ServletWebRequestHttpMethodsTests.java b/spring-web/src/test/java/org/springframework/web/context/request/ServletWebRequestHttpMethodsTests.java
index 3832ae3a0b4..6dd2adf9edf 100644
--- a/spring-web/src/test/java/org/springframework/web/context/request/ServletWebRequestHttpMethodsTests.java
+++ b/spring-web/src/test/java/org/springframework/web/context/request/ServletWebRequestHttpMethodsTests.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.
@@ -16,6 +16,8 @@
package org.springframework.web.context.request;
+import static org.junit.Assert.*;
+
import java.text.SimpleDateFormat;
import java.util.Arrays;
import java.util.Date;
@@ -32,8 +34,6 @@ import org.junit.runners.Parameterized.Parameters;
import org.springframework.mock.web.test.MockHttpServletRequest;
import org.springframework.mock.web.test.MockHttpServletResponse;
-import static org.junit.Assert.*;
-
/**
* Parameterized tests for ServletWebRequest
* @author Juergen Hoeller
@@ -293,4 +293,28 @@ public class ServletWebRequestHttpMethodsTests {
assertEquals(dateFormat.format(epochTime), servletResponse.getHeader("Last-Modified"));
}
+ @Test
+ public void checkNotModifiedTimestampConditionalPut() throws Exception {
+ long currentEpoch = currentDate.getTime();
+ long oneMinuteAgo = currentEpoch - (1000 * 60);
+ servletRequest.setMethod("PUT");
+ servletRequest.addHeader("If-UnModified-Since", currentEpoch);
+
+ assertFalse(request.checkNotModified(oneMinuteAgo));
+ assertEquals(200, servletResponse.getStatus());
+ assertEquals(null, servletResponse.getHeader("Last-Modified"));
+ }
+
+ @Test
+ public void checkNotModifiedTimestampConditionalPutConflict() throws Exception {
+ long currentEpoch = currentDate.getTime();
+ long oneMinuteAgo = currentEpoch - (1000 * 60);
+ servletRequest.setMethod("PUT");
+ servletRequest.addHeader("If-UnModified-Since", oneMinuteAgo);
+
+ assertTrue(request.checkNotModified(currentEpoch));
+ assertEquals(412, servletResponse.getStatus());
+ assertEquals(null, servletResponse.getHeader("Last-Modified"));
+ }
+
}
diff --git a/src/asciidoc/web-mvc.adoc b/src/asciidoc/web-mvc.adoc
index 2f82b89af83..2db3fc036b4 100644
--- a/src/asciidoc/web-mvc.adoc
+++ b/src/asciidoc/web-mvc.adoc
@@ -4449,17 +4449,24 @@ This can be achieved as follows:
----
There are two key elements here: calling `request.checkNotModified(lastModified)` and
-returning `null`. The former sets the response status to 304 before it returns `true`.
+returning `null`. The former sets the appropriate response status and headers
+before it returns `true`.
The latter, in combination with the former, causes Spring MVC to do no further
processing of the request.
Note that there are 3 variants for this:
* `request.checkNotModified(lastModified)` compares lastModified with the
-`'If-Modified-Since'` request header
-* `request.checkNotModified(eTag)` compares eTag with the `'ETag'` request header
+`'If-Modified-Since'` or `'If-Unmodified-Since'` request header
+* `request.checkNotModified(eTag)` compares eTag with the `'If-None-Match'` request header
* `request.checkNotModified(eTag, lastModified)` does both, meaning that both
-conditions should be valid for the server to issue an `HTTP 304 Not Modified` response
+conditions should be valid
+
+When receiving conditional `'GET'`/`'HEAD'` requests, `checkNotModified` will check
+that the resource has not been modified and if so, it will result in a `HTTP 304 Not Modified`
+response. In case of conditional `'POST'`/`'PUT'`/`'DELETE'` requests, `checkNotModified`
+will check that the resource has not been modified and if it has been, it will result in a
+`HTTP 409 Precondition Failed` response to prevent concurrent modifications.
[[mvc-httpcaching-shallowetag]]