The core interfaces and classes of the HTTP components.
| ConnectionReuseStrategy | Interface for deciding whether a connection should be kept alive. |
| FormattedHeader | An HTTP header which is already formatted. |
| Header | Represents an HTTP header field. |
| HeaderElement | One element of an HTTP header value. |
| HeaderElementIterator | A type-safe iterator for HeaderElement objects. |
| HeaderIterator | A type-safe iterator for Header objects. |
| HttpClientConnection | An HTTP connection for use on the client side. |
| HttpConnection | A generic HTTP connection, useful on client and server side. |
| HttpConnectionMetrics | The point of access to the statistics of an HttpConnection. |
| HttpEntity | An entity that can be sent or received with an HTTP message. |
| HttpEntityEnclosingRequest | A request with an entity. |
| HttpInetConnection | An HTTP connection over the Internet Protocol (IP). |
| HttpMessage | A generic HTTP message. |
| HttpRequest | An HTTP request. |
| HttpRequestFactory | A factory for HttpRequest objects. |
| HttpRequestInterceptor | Processes a request. |
| HttpResponse | An HTTP response. |
| HttpResponseFactory | A factory for HttpResponse objects. |
| HttpResponseInterceptor | Processes a response. |
| HttpServerConnection | An HTTP connection for use on the server side. |
| HttpStatus | Constants enumerating the HTTP status codes. |
| NameValuePair | A simple class encapsulating an attribute/value pair. |
| ReasonPhraseCatalog | Interface for obtaining reason phrases for HTTP status codes. |
| RequestLine | The first line of an HttpRequest. |
| StatusLine | Represents a status line as returned from a HTTP server. |
| TokenIterator | An iterator for String tokens. |
| HttpHost | Holds all of the variables needed to describe an HTTP connection to a host. |
| HttpVersion | Represents an HTTP version, as specified in RFC 2616. |
| ProtocolVersion | Represents a protocol version, as specified in RFC 2616. |
| ConnectionClosedException | Indicates that a connection has been closed. |
| HttpException | Signals that an HTTP exception has occurred. |
| MalformedChunkCodingException | Signals a malformed chunked stream. |
| MethodNotSupportedException | Indicates that an HTTP method is not supported. |
| NoHttpResponseException | Signals that the target server failed to respond with a valid HTTP response. |
| ParseException | Indicates a parse error. |
| ProtocolException | Signals that an HTTP protocol violation has occurred. |
| UnsupportedHttpVersionException | Indicates an unsupported version of the HTTP protocol. |