code: public boolean isSupported() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
          // Note that this may return 'null' but SDM's supportsFeature() does the right thing™ then.
          Jid archiveAddress = getArchiveAddress();
          return serviceDiscoveryManager.supportsFeature(archiveAddress, MamElements.NAMESPACE);
      }
docs: Check if this MamManager's archive address supports MAM.
  
  @return true if MAM is supported, <code>false</code>otherwise.
  
  @throws NoResponseException
  @throws XMPPErrorException
  @throws NotConnectedException
  @throws InterruptedException
  @since 4.2.1
  @see <a href="https://xmpp.org/extensions/xep-0313.html#support">XEP-0313 § 7. Determining support</a>