New Data Dictionary interface in EMA C++

@Akechi Sato

There are several improvements in EMA 3.1.0.
In term of Data Dictionary, I found new classes from EMA Reference Manual
(<EMA Install Folder>\Docs\refman\ema). You should be able to use below
classes to access EMA data dictionary

• DataDictionary (thomsonreuters::ema::rdm)
• DictionaryEntry
  (thomsonreuters::ema::rdm)
• DictionaryUtility
  (thomsonreuters::ema::rdm)

Also in this version, FieldEntry class provide
method to get Enum display by using getEnumDisplay() method.

The new version implements features
which allow you to get access to the internal EMA dictionary via the
thomsonreuters::ema::rdm::DataDictioanry class. The EMA’s DataDictionary is the
Dictionary utility which provides the same capability as same as the
RsslDataDictionary in ETA C. The example
"332__Dictionary__Streaming" also update to use the class to decode downloaded
Data Dictionary.

Moreover application can extract a
DataDictionary object used by FieldList when decoding it via the
DictionaryUtility::dataDictionary() static method. But The DataDictionary is
valid only in the context of a callback method according to EMA Reference
Manual.

DataDictionary and DictionaryEntry class also
provide interfaces to get Dictionary information such as EnumTables,
DictionaryID, FieldVersion, EnumRecordTemplateVersion.

Below is snippet of codes I used to access
Dictionary data such as Fid ID, Fid Acronym and print Enum table in case that
the Fid is Enumerate field. I have tested the codes with
332_Dictionary_Streaming example and change codes in AppClient::decode to print
dictionary after it received both RWFFld and RWFEnum dictionary.

if (fldDictComplete && enumTypeComplete)
{
    const EmaVector<DictionaryEntry>& dictEntries =
dataDictionary.getEntries();
    for (int index=0; index < dictEntries.size(); index++)
    { 
               int fidID = dictEntries[index].getFid();
               std::cout<< "FID[" << fidID << "][" <<
dictEntries[index].getAcronym() << "]" << endl;

               if(dictEntries[index].hasEnumTypeTable())
               {
                   const EnumTypeTable& enumTable = dictEntries[index].getEnumTypeTable();
		   const EmaVector<EnumType>& enumType = enumTable.getEnumTypes();
                   for(int i = 0; i < enumType.size(); i++)
                   {
		      EmaString displayTxt;
                      displayTxt.append(enumType[i].getDisplay());
                      cout<< "\t Enum [" << enumType[i].getValue() << "]
Display[" << displayTxt << "]" << endl;
                    }
               }
     }
}

And below is output when running the example
with modified codes

…


FID[12][HIGH_1]
FID[13][LOW_1]
FID[14][PRCTCK_1]
                Enum [0] Display[ ]
                Enum [1] Display[Þ]
                Enum [2] Display[þ]
                Enum [3] Display[ ]
                Enum [4] Display[0]
                Enum [5] Display[U]
                Enum [6] Display[D]
                Enum [7] Display[+]
                Enum [8] Display[-]
FID[15][CURRENCY]
                Enum [0] Display[   ]
                Enum [4] Display[AFA]
                Enum [8] Display[ALL]
                Enum [12] Display[DZD]
                Enum [20] Display[ADP]
                Enum [24] Display[AON]
                Enum [32] Display[ARS]
                Enum [36] Display[AUD]
                Enum [37] Display[AUc]
                Enum [40] Display[ATS]
                Enum [44] Display[BSD]
                Enum [48] Display[BHD]
                Enum [50] Display[BDT]
                Enum [51] Display[AMD]
                Enum [52] Display[BBD]
                Enum [56] Display[BEF]
                Enum [60] Display[BMD]
                Enum [64] Display[BTN]
                Enum [68] Display[BOB]
                Enum [70] Display[BAD]
                Enum [72] Display[BWP]
                Enum [76] Display[BRL]
...