// 	If-None-Match condition evaluates to false , and;
			//  If-Modified-Since condition evaluates to true ;
			// 	Then Amazon S3 returns the 304 Not Modified response code.
			// 2. If If-Modified-Since condition evaluates to false, The following `ifModifiedSinceHeader` judgment will also return 304

			// If the object ETag matches with the specified ETag.
			writeHeadersPrecondition(w, objInfo)
			w.WriteHeader(http.StatusNotModified)

* **`300 - 399`** are for "Redirection".  Responses with these status codes may or may not have a body, except for `304`, "Not Modified", which must not have one.
* **`400 - 499`** are for "Client error" responses. These are the second type you would probably use the most.
    * An example is `404`, for a "Not Found" response.

                    processor.setTransformer(container.getComponent("fileTransformer"));
                    processor.setSuccessfulHttpCodes(new int[] { 200 });
                    processor.setNotModifiedHttpCodes(new int[] { 304 });
                })//
                .<RegexRule> singleton("fileRule", RegexRule.class, rule -> {
                    rule.setRuleId("fileRule");
                    rule.setDefaultRule(true);

    assertCached(false, 207)
    assertCached(true, 300)
    assertCached(true, 301)
    assertCached(true, 302)
    assertCached(false, 303)
    assertCached(false, 304)
    assertCached(false, 305)
    assertCached(false, 306)
    assertCached(true, 307)
    assertCached(true, 308)
    assertCached(false, 400)
    assertCached(false, 401)
    assertCached(false, 402)

// The responses for fetching the object when If-Modified-Since
// and If-Unmodified-Since headers set are validated.
// If-Modified-Since - Return the object only if it has been modified since the specified time, else return a 304 (not modified).
// If-Unmodified-Since - Return the object only if it has not been modified since the specified time, else return a 412 (precondition failed).
func (s *TestSuiteCommon) TestHeadOnObjectLastModified(c *check) {

    // Check the network response. It has the caller's request, plus some caching headers.
    cacheHit
      .networkResponse()
      .assertCode(304)
      .assertHeader("Donut", "b")
      .assertRequestHeader("Accept-Language", "en-US")
      .assertRequestHeader("Accept-Charset", "UTF-8")