Merge "Process response bodies only when present"

src/main/java/com/android/volley/toolbox/HurlStack.java

@@ -23,6 +23,7 @@
 import org.apache.http.Header;
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
+import org.apache.http.HttpStatus;
 import org.apache.http.ProtocolVersion;
 import org.apache.http.StatusLine;
 import org.apache.http.entity.BasicHttpEntity;
@@ -115,7 +116,9 @@ public HttpResponse performRequest(Request<?> request, Map<String, String> addit
         StatusLine responseStatus = new BasicStatusLine(protocolVersion,
                 connection.getResponseCode(), connection.getResponseMessage());
         BasicHttpResponse response = new BasicHttpResponse(responseStatus);
-        response.setEntity(entityFromConnection(connection));
+        if (hasResponseBody(request.getMethod(), responseStatus.getStatusCode())) {
+            response.setEntity(entityFromConnection(connection));
+        }
         for (Entry<String, List<String>> header : connection.getHeaderFields().entrySet()) {
             if (header.getKey() != null) {
                 Header h = new BasicHeader(header.getKey(), header.getValue().get(0));
@@ -125,6 +128,20 @@ public HttpResponse performRequest(Request<?> request, Map<String, String> addit
         return response;
     }
 
+    /**
+     * Checks if a response message contains a body.
+     * @see <a href="https://tools.ietf.org/html/rfc7230#section-3.3">RFC 7230 section 3.3</a>
+     * @param requestMethod request method
+     * @param responseCode response status code
+     * @return whether the response has a body
+     */
+    private static boolean hasResponseBody(int requestMethod, int responseCode) {
+        return requestMethod != Request.Method.HEAD
+            && !(HttpStatus.SC_CONTINUE <= responseCode && responseCode < HttpStatus.SC_OK)
+            && responseCode != HttpStatus.SC_NO_CONTENT
+            && responseCode != HttpStatus.SC_NOT_MODIFIED;
+    }
+
     /**
      * Initializes an {@link HttpEntity} from the given {@link HttpURLConnection}.
      * @param connection