code: protected boolean isButtonEnabledForHttpMessageContainerState(HttpMessageContainer httpMessageContainer) {
          boolean enabled = isButtonEnabledForNumberOfSelectedMessages(httpMessageContainer);
  
          if (enabled) {
              enabled = isButtonEnabledForSelectedMessages(httpMessageContainer);
          }
  
          return enabled;
      }
docs: Tells whether or not the button should be enabled for the state of the given message container. Called from
  {@code isEnableForMessageContainer(MessageContainer)}.
  <p>
  By default, is only enabled if both methods {@code isButtonEnabledForNumberOfSelectedMessages(HttpMessageContainer)} and
  {@code isButtonEnabledForSelectedMessages(HttpMessageContainer)} (called only if the former method returns {@code true})
  return {@code true}.<br>
  </p>
  <p>
  Not normally overridden.
  </p>
  
  @param httpMessageContainer the message container that will be evaluated
  @return {@code true} if the button should be enabled for the message container, {@code false} otherwise.
  @see #isEnableForMessageContainer(MessageContainer)
  @see #isButtonEnabledForNumberOfSelectedMessages(HttpMessageContainer)
  @see #isButtonEnabledForSelectedMessages(HttpMessageContainer)