| HostNameResolver | |
| LayeredSocketFactory | A SocketFactory for layered sockets (SSL/TLS). |
| SocketFactory | A factory for creating and connecting sockets. |
| PlainSocketFactory | The default class for creating sockets. |
| Scheme | Encapsulates specifics of a protocol scheme such as "http" or "https". |
| SchemeRegistry | A set of supported protocol schemes. |
