Specifies the type of RFC message part handled by an Indy message decoder.

Implements a decoder for RFC-822 compliant message parts.

Represents information about registered decoder classes and detects coder usage for message part contents.

Provides a framework for registering and retrieving decoder classes for RFC 822 message parts.

Implements an encoder for RFC-822 compliant message parts.

Represents information about registered encoder classes and generates RFC message headers for the encoder class.

Container for registered encoder classes, with methods to create, access, and release registered encoder classes.