DCCL v4
dccl::v3::PresenceBitCodec< WrappedType > Class Template Reference

Encodes empty optional fields with a single "presence" bit. More...

#include <dccl/codecs3/field_codec_presence.h>

Inheritance diagram for dccl::v3::PresenceBitCodec< WrappedType >:

Public Types

typedef TypedFieldCodec< typename WrappedType::wire_type, typename WrappedType::field_type > Base
 
typedef WrappedType wrapped_type
 The codec type of the "wrapped" codec.
 
typedef Base::wire_type wire_type
 The wire_type of the "wrapped" codec.
 
typedef Base::field_type field_type
 The field_type of the "wrapped" codec.
 
- Public Types inherited from dccl::TypedFieldCodec< WrappedType::wire_type, WrappedType::field_type >
typedef WrappedType::wire_type wire_type
 
typedef WrappedType::field_type field_type
 

Public Member Functions

virtual wire_type pre_encode (const field_type &field_value)
 
virtual field_type post_decode (const wire_type &wire_value)
 
virtual void validate ()
 Calls _inner_codec.validate()
 
virtual Bitset encode ()
 Encodes an empty field as a single 0 bit.
 
virtual Bitset encode (const wire_type &value)
 Encodes a non-empty field, adding a 1 bit to the front for optional fields.
 
virtual wire_type decode (Bitset *bits)
 Decodes a field, first evaluating the presence bit if necessary.
 
virtual unsigned size ()
 Size of an empty field (1 bit)
 
virtual unsigned size (const wire_type &wire_value)
 Size of a non-empty field; gets size from "wrapped" codec, adds 1 for optional fields.
 
virtual unsigned max_size ()
 Calculate maximum size of the field in bits. More...
 
virtual unsigned min_size ()
 Calculate minimum size of the field in bits. More...
 
- Public Member Functions inherited from dccl::TypedFieldCodec< WrappedType::wire_type, WrappedType::field_type >
virtual Bitset encode (const WrappedType::wire_type &wire_value)=0
 Encode a non-empty field. More...
 
virtual unsigned size (const WrappedType::wire_type &wire_value)=0
 Calculate the size (in bits) of a non-empty field. More...
 
- Public Member Functions inherited from dccl::FieldCodecSelector< WrappedType::wire_type, WrappedType::field_type >
virtual WrappedType::wire_type pre_encode (const WrappedType::field_type &field_value)=0
 Convert from the FieldType representation (used in the Google Protobuf message) to the WireType representation (used with encode() and decode(), i.e. "on the wire"). More...
 
virtual WrappedType::field_type post_decode (const WrappedType::wire_type &wire_value)=0
 Convert from the WireType representation (used with encode() and decode(), i.e. "on the wire") to the FieldType representation (used in the Google Protobuf message). More...
 
- Public Member Functions inherited from dccl::FieldCodecBase
 FieldCodecBase ()
 
virtual ~FieldCodecBase ()
 
void base_encode (Bitset *bits, const google::protobuf::Message &msg, MessagePart part, bool strict)
 Encode this part (body or head) of the base message. More...
 
void base_size (unsigned *bit_size, const google::protobuf::Message &msg, MessagePart part)
 Calculate the size (in bits) of a part of the base message when it is encoded. More...
 
void base_decode (Bitset *bits, google::protobuf::Message *msg, MessagePart part)
 Decode part of a message. More...
 
void base_max_size (unsigned *bit_size, const google::protobuf::Descriptor *desc, MessagePart part)
 Calculate the maximum size of a message given its Descriptor alone (no data) More...
 
void base_min_size (unsigned *bit_size, const google::protobuf::Descriptor *desc, MessagePart part)
 Calculate the minimum size of a message given its Descriptor alone (no data) More...
 
void base_validate (const google::protobuf::Descriptor *desc, MessagePart part)
 Validate this part of the message to make sure all required extensions are set. More...
 
void base_info (std::ostream *os, const google::protobuf::Descriptor *desc, MessagePart part)
 Get human readable information (size of fields, etc.) about this part of the DCCL message. More...
 
std::string name () const
 the name of the codec used to identifier it in the .proto custom option extension
 
google::protobuf::FieldDescriptor::Type field_type () const
 the type exposed to the user in the original and decoded Protobuf messages More...
 
google::protobuf::FieldDescriptor::CppType wire_type () const
 the C++ type used "on the wire". This is the type visible after pre_encode and before post_decode functions are called. More...
 
const google::protobuf::FieldDescriptor * this_field () const
 Returns the FieldDescriptor (field schema meta-data) for this field. More...
 
void set_force_use_required (bool force_required=true)
 Force the codec to always use the "required" field encoding, regardless of the FieldDescriptor setting. Useful when wrapping this codec in another that handles optional and repeated fields.
 
void field_pre_encode (boost::any *wire_value, const boost::any &field_value)
 Pre-encodes a non-repeated (i.e. optional or required) field by converting the FieldType representation (the Google Protobuf representation) into the WireType representation (the type used in the encoded DCCL message). This allows for type-converting codecs. More...
 
void field_pre_encode_repeated (std::vector< boost::any > *wire_values, const std::vector< boost::any > &field_values)
 Pre-encodes a repeated field. More...
 
void field_encode (Bitset *bits, const boost::any &field_value, const google::protobuf::FieldDescriptor *field)
 Encode a non-repeated field. More...
 
void field_encode_repeated (Bitset *bits, const std::vector< boost::any > &field_values, const google::protobuf::FieldDescriptor *field)
 Encode a repeated field. More...
 
void field_size (unsigned *bit_size, const boost::any &field_value, const google::protobuf::FieldDescriptor *field)
 Calculate the size of a field. More...
 
void field_size_repeated (unsigned *bit_size, const std::vector< boost::any > &field_values, const google::protobuf::FieldDescriptor *field)
 Calculate the size of a repeated field. More...
 
void field_decode (Bitset *bits, boost::any *field_value, const google::protobuf::FieldDescriptor *field)
 Decode a non-repeated field. More...
 
void field_decode_repeated (Bitset *bits, std::vector< boost::any > *field_values, const google::protobuf::FieldDescriptor *field)
 Decode a repeated field. More...
 
void field_post_decode (const boost::any &wire_value, boost::any *field_value)
 Post-decodes a non-repeated (i.e. optional or required) field by converting the WireType (the type used in the encoded DCCL message) representation into the FieldType representation (the Google Protobuf representation). This allows for type-converting codecs. More...
 
void field_post_decode_repeated (const std::vector< boost::any > &wire_values, std::vector< boost::any > *field_values)
 Post-decodes a repeated field. More...
 
void field_max_size (unsigned *bit_size, const google::protobuf::FieldDescriptor *field)
 Calculate the upper bound on this field's size (in bits) More...
 
void field_min_size (unsigned *bit_size, const google::protobuf::FieldDescriptor *field)
 Calculate the lower bound on this field's size (in bits) More...
 
void field_validate (bool *b, const google::protobuf::FieldDescriptor *field)
 Validate this field, checking that all required option extensions are set (e.g. (dccl.field).max and (dccl.field).min for arithmetic codecs) More...
 
void field_info (std::ostream *os, const google::protobuf::FieldDescriptor *field)
 Write human readable information about the field and its bounds to the provided stream. More...
 
dccl::DCCLFieldOptions dccl_field_options () const
 Get the DCCL field option extension value for the current field. More...
 
void require (bool b, const std::string &description)
 Essentially an assertion to be used in the validate() virtual method. More...
 
DynamicConditionsdynamic_conditions (const google::protobuf::FieldDescriptor *field)
 

Protected Attributes

WrappedType _inner_codec
 Instance of the "wrapped" codec.
 

Additional Inherited Members

- Static Public Member Functions inherited from dccl::FieldCodecBase
static const google::protobuf::Descriptor * this_descriptor ()
 Returns the Descriptor (message schema meta-data) for the immediate parent Message. More...
 
static const google::protobuf::Messagethis_message ()
 
static const google::protobuf::Messageroot_message ()
 
static bool has_codec_group ()
 
static std::string codec_group (const google::protobuf::Descriptor *desc)
 
static std::string codec_group ()
 
static int codec_version ()
 
static MessagePart part ()
 the part of the message currently being encoded (head or body).
 
static bool strict ()
 
- Protected Member Functions inherited from dccl::FieldCodecBase
bool use_required ()
 Whether to use the required or optional encoding.
 
virtual std::string info ()
 Write field specific information (in addition to general information such as sizes that are automatically written by this class for all fields. More...
 
virtual void any_encode_repeated (Bitset *bits, const std::vector< boost::any > &wire_values)
 
virtual void any_decode_repeated (Bitset *repeated_bits, std::vector< boost::any > *field_values)
 
virtual void any_pre_encode_repeated (std::vector< boost::any > *wire_values, const std::vector< boost::any > &field_values)
 
virtual void any_post_decode_repeated (const std::vector< boost::any > &wire_values, std::vector< boost::any > *field_values)
 
virtual unsigned any_size_repeated (const std::vector< boost::any > &wire_values)
 
virtual unsigned max_size_repeated ()
 
virtual unsigned min_size_repeated ()
 
void check_repeat_settings ()
 

Detailed Description

template<typename WrappedType>
class dccl::v3::PresenceBitCodec< WrappedType >

Encodes empty optional fields with a single "presence" bit.

This class wraps an existing TypedFieldCodec, adding an extra "presence" bit to the LSB for optional fields. The field size is as follows:

  • Optional
    • Empty: 1 bit
    • Non-empty: size of WrappedType + 1
  • Required
    • Empty: size of WrappedType
    • Non-empty: size of WrappedType

Definition at line 45 of file field_codec_presence.h.

Member Function Documentation

◆ max_size()

template<typename WrappedType >
virtual unsigned dccl::v3::PresenceBitCodec< WrappedType >::max_size ( )
inlinevirtual

Calculate maximum size of the field in bits.

Returns
Maximum size of this field (in bits).

Implements dccl::FieldCodecBase.

Definition at line 139 of file field_codec_presence.h.

◆ min_size()

template<typename WrappedType >
virtual unsigned dccl::v3::PresenceBitCodec< WrappedType >::min_size ( )
inlinevirtual

Calculate minimum size of the field in bits.

Returns
Minimum size of this field (in bits).

Implements dccl::FieldCodecBase.

Definition at line 152 of file field_codec_presence.h.


The documentation for this class was generated from the following file: