Java SSL connect, add server cert to keystore programmatically

I am connecting an SSL client to my SSL server. When the client fails to verify a certificate due to the root not existing in the client's key store, I need the option to add that certificate to the local key store in code and continue. There are examples for always accepting all certificates, but I want the user to verify the cert and add it to local key store without leaving the application.

SSLSocketFactory sslsocketfactory = (SSLSocketFactory) SSLSocketFactory.getDefault();
SSLSocket sslsocket = (SSLSocket) sslsocketfactory.createSocket("localhost", 23467);
try{
    sslsocket.startHandshake();
} catch (IOException e) {
    //here I want to get the peer's certificate, conditionally add to local key store, then reauthenticate successfully
}

There is a whole lot of stuff about custom SocketFactory, TrustManager, SSLContext, etc and I don't really understand how they all fit together or which would be the shortest path to my goal.