com.refinitiv.eta.valueadd.cache

Interface PayloadEntry

public interface PayloadEntry

PayloadEntry stores the last known or applied value of an OMM item. PayloadEntry efficiently stores OMM containers (one per entry), e.g. FieldList, Map, Series, Vector, FilterList or ElementList. Note
- usage of OMM FieldList requires that RDM Field Dictionary information is set with the cache instance prior to storing this FieldList in PayloadEntry.
- OMM data types of Opaque and XML are not supported.

See Also:

PayloadCache, PayloadCursor, CacheError

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	PayloadEntry.PayloadEntryTraceFormat Trace format options in which to display a decoded output of the payload entry data.

Method Summary

Modifier and Type	Method and Description
int	apply(com.refinitiv.eta.codec.DecodeIterator dIter, com.refinitiv.eta.codec.Msg msg, CacheError error) Applies the partially decoded Msg to the payload entry.
void	clear() Clears the OMM data contents of this entry.
short	dataType() Returns the payload entry data type When the entry is first created, or cleared, returns DataTypes.UNKNOWN.
void	destroy() Removes the payload entry from its cache and destroys the entry.
int	retrieve(com.refinitiv.eta.codec.EncodeIterator eIter, PayloadCursor cursor, CacheError error) Retrieves encoded OMM data from the cache payload entry.
int	trace(int traceFormat, java.io.PrintWriter fileWriter, com.refinitiv.eta.codec.DataDictionary dictionary) Display the cache payload entry contents by writing to the given fileWriter.

Method Detail

apply

int apply(com.refinitiv.eta.codec.DecodeIterator dIter,
          com.refinitiv.eta.codec.Msg msg,
          CacheError error)

Applies the partially decoded Msg to the payload entry. The OMM container in the message payload is applied to the cache entry following the OMM rules of the message and the container type. When this function returns an error (< CodecReturnCodes.SUCCESS), some or all of the data could not be cached. Some errors returned by this function can be handled as warnings, depending on application requirements. When the function returns an error code, the CacheError errorId can be tested for a warning indication. For errors, errorId will have the same value as the function return value. For warnings, errorId will be set to CodecReturnCodes.SUCCESS. The CacheError text can be reviewed for further explanation about the errors or warnings. Examples of warning conditions: data truncated for exceeding size allocated in the field dictionary; fields in an update Msg ignored if they were not in the refresh Msg.

Parameters:

dIter - The decode iterator positioned at the payload of the message

msg - The partially decoded message structure

error - The error information structure will be populated if the payload data from the message could not be written to the cache entry

Returns:

Returns failure codes (< CodecReturnCodes.SUCCESS) if the data could not be applied to the cache entry

retrieve

int retrieve(com.refinitiv.eta.codec.EncodeIterator eIter,
             PayloadCursor cursor,
             CacheError error)

Retrieves encoded OMM data from the cache payload entry. This function encodes data from the cache entry into the buffer provided with the eIter parameter. The retrieval process will attempt to encode the entire container into the given buffer, but also supports multi-part retrieval for OMM containers that support fragmentation. (Note that FieldList and ElementList containers must be retrieved in a single part). If the application does not wish to use fragmentation, it should pass a null PayloadCursor. For multi-part retrieval, a PayloadCursor is required. The application will call this function to retrieve fragments of the cached container until the cursor indicates the final part has been retrieved (PayloadCursor.isComplete). The size of the buffer provided for retrieval will determine the number of fragments needed to encode the entire container.

Parameters:

eIter - The OMM payload data in the cache entry will be encoded into the buffer associated with this iterator.

cursor - The cursor is required to support multi-part (fragmented) retrieval of the OMM data in the cache entry. Clear the cursor (PayloadCursor.clear) prior to the first retrieval from the payload entry. The cursor is not needed for single part retrieval.

error - The error in formation structure will be populated if payload entry cache data could not be retrieved.

Returns:

Failure codes (< CodecReturnCodes.SUCCESS) if data could not be retrieved from the container. - CodecReturnCodes.BUFFER_TOO_SMALL indicates that the buffer size should be increased in order to retrieve the data from the entry (single part or multi-part). - CodecReturnCodes.SUCCESS is returned when data is successfully encoded into the buffer, or if there is no data to retrieve from the entry. - Note that for multi-part retrieval, CodecReturnCodes.SUCCESS only indicates the successful encoding of the current fragment. Check the state of the PayloadCursor to determine if the current fragment is the final part.

dataType

short dataType()

Returns the payload entry data type When the entry is first created, or cleared, returns DataTypes.UNKNOWN.

Returns:

The OMM data type of this container.

destroy

void destroy()

Removes the payload entry from its cache and destroys the entry.

clear

void clear()

Clears the OMM data contents of this entry. The entry remains in the cache and can be re-used.

trace

int trace(int traceFormat,
          java.io.PrintWriter fileWriter,
          com.refinitiv.eta.codec.DataDictionary dictionary)

Display the cache payload entry contents by writing to the given fileWriter.

Parameters:

traceFormat - Option for specifying the type of information displayed for the entry

fileWriter - The file writer where the trace information will be written. Supports write into a file or standard output.

dictionary - The dictionary structure used to decode the OMM data from the cache entry

Returns:

Returns failure code if trace function fails