code: public void decrypt (byte[] key)
          throws IOException, ClassNotFoundException
      {
          if (_clearCreds != null) {
              return;
          }
          _key = key;
          try {
             _contents = SecureUtil.getAESCipher(Cipher.DECRYPT_MODE, _key).doFinal(_contents);
          } catch (GeneralSecurityException gse) {
              IOException ioe = new IOException("Failed to decrypt credentials");
              ioe.initCause(gse);
              throw ioe;
          }
  
          ByteArrayInputStream byteIn = new ByteArrayInputStream(_contents);
          ObjectInputStream cipherIn = new ObjectInputStream(byteIn);
          _clearCreds = (Credentials)cipherIn.readObject();
      }
docs: Decrypts the request after transmission.