WalletAppKit creates an address every time Bitcoinj gets initialized
According to the documentation:


  getImportedKeys() returns a list of the non-deterministic keys that
  have been imported into the wallet, or the empty list if none.


Try to change:

if (wallet().getImportedKeys().size() &lt; 1)
    wallet().importKey(new ECKey());


to:

if (wallet().getIssuedReceiveKeys().size() &lt; 1)
    wallet().freshReceiveKey();


To get the first address in your wallet, you can use:

wallet.getIssuedReceiveKeys().get(0).toAddress(TestNet3Params.get()).toBase58().toString();