code: public void addPublicKey(PublicKey key, NetworkParameters network) {
        Address address = Address.fromStandardPublicKey(key, network);
        _addresses.add(address);
        _addressSet.add(address);
        _publicKeys.put(address, key);
     }
docs: Add a public key to the key ring.
  
  @param key public key
  @param network Bitcoin network to talk to