http Issue 225: When redirects on 303 are changed to GET, they must have empty

content
https://code.google.com/p/google-http-java-client/issues/detail?id=225
https://codereview.appspot.com/13094046/

Author: ngmiceli-g

google-http-client/src/main/java/com/google/api/client/http/HttpRequest.java

@@ -1102,6 +1102,12 @@ public Future<HttpResponse> executeAsync() {
    * {@code "If-*"} request headers.
    * </p>
    *
+   * <p>
+   * Upgrade warning: When handling a status code of 303, {@link #handleRedirect(int, HttpHeaders)}
+   * now correctly removes any content from the body of the new request, as GET requests should not
+   * have content. It did not do this in prior version 1.16.
+   * </p>
+   *
    * @return whether the redirect was successful
    * @since 1.11
    */
@@ -1114,6 +1120,8 @@ public boolean handleRedirect(int statusCode, HttpHeaders responseHeaders) {
       // on 303 change method to GET
       if (statusCode == HttpStatusCodes.STATUS_CODE_SEE_OTHER) {
         setRequestMethod(HttpMethods.GET);
+        // GET requests do not support non-zero content length
+        setContent(null);
       }
       // remove Authorization and If-* headers
       headers.setAuthorization((String) null);

google-http-client/src/test/java/com/google/api/client/http/HttpRequestTest.java

@@ -19,10 +19,10 @@
 import com.google.api.client.testing.http.MockHttpUnsuccessfulResponseHandler;
 import com.google.api.client.testing.http.MockLowLevelHttpRequest;
 import com.google.api.client.testing.http.MockLowLevelHttpResponse;
+import com.google.api.client.testing.util.LogRecordingHandler;
 import com.google.api.client.testing.util.MockBackOff;
 import com.google.api.client.testing.util.MockSleeper;
 import com.google.api.client.util.BackOff;
-import com.google.api.client.testing.util.LogRecordingHandler;
 import com.google.api.client.util.Key;
 import com.google.api.client.util.LoggingStreamingContent;
 import com.google.api.client.util.StringUtils;
@@ -319,6 +319,8 @@ public void test303Redirect() throws Exception {
     Assert.assertEquals(2, fakeTransport.lowLevelExecCalls);
     // Assert that the method in the request was changed to a GET due to the 303.
     Assert.assertEquals(HttpMethods.GET, request.getRequestMethod());
+    // Assert that the content is null, since GET requests don't support non-zero content-length
+    Assert.assertNull(request.getContent());
   }
 
   public void testInfiniteRedirects() throws Exception {