How to cache received EMA data for later use?

In an application that subscribes to MarketPrice instruments
using EMA Java, I would like to preserve for a later use the Data I receive via
Refresh and Update messages. My current understanding is that the Data I
receive for each field is only valid in the context of the onRefresh and onUpdate
callback methods. For example if in an onRefresh method I preserve the Data of
a FieldEntry by calling fieldData = fieldEntry.load(), I cannot use this fieldData
variable later after onRefresh returned.
- Can you please confirm if my understanding is correct?
- If yes, is there an easy way to clone the received data
for later reuse, out of the onRefresh/onUpdate callback methods? By easy way I mean
something like fieldData = fieldEntry.load().clone(). In order to avoid being
too much coupled with the EMA Data types, I would like to avoid a big switch
that deals with every possible data type.
Best Answer
-
Based on EMA Java API dev guide section 3.2.3, the Data class and all classes that inherit from it are designed as temporary and short-lived objects. For this reason, do not use them as storage or caching devices.
If the application just needs the content for the
business logic use case, the application can store the FieldEntry’s content as
string or manual copy content from incoming FieldEntry object (A) to the local FieldEntry object (B).Based on your "For example if in an onRefresh method I preserve the Data of a FieldEntry by calling fieldData = fieldEntry.load(), I cannot use this fieldData variable later after onRefresh returned." statement, your fieldData is declared under the onRefresh() function scope. You cannot use it outside the onRefresh() function. You need to declare the local FieldEntry object in the class scope, so it can be used in any class's functions.
0
Answers
-
Hi Wasin,
Thank you very much for this answer.
Given what the doc says, I'm not even sure that what you proposed in your last sentence will work.
0
Categories
- All Categories
- 3 Polls
- 6 AHS
- 36 Alpha
- 166 App Studio
- 6 Block Chain
- 4 Bot Platform
- 18 Connected Risk APIs
- 47 Data Fusion
- 34 Data Model Discovery
- 684 Datastream
- 1.4K DSS
- 615 Eikon COM
- 5.2K Eikon Data APIs
- 10 Electronic Trading
- Generic FIX
- 7 Local Bank Node API
- 3 Trading API
- 2.9K Elektron
- 1.4K EMA
- 248 ETA
- 554 WebSocket API
- 37 FX Venues
- 14 FX Market Data
- 1 FX Post Trade
- 1 FX Trading - Matching
- 12 FX Trading – RFQ Maker
- 5 Intelligent Tagging
- 2 Legal One
- 23 Messenger Bot
- 3 Messenger Side by Side
- 9 ONESOURCE
- 7 Indirect Tax
- 60 Open Calais
- 275 Open PermID
- 44 Entity Search
- 2 Org ID
- 1 PAM
- PAM - Logging
- 6 Product Insight
- Project Tracking
- ProView
- ProView Internal
- 22 RDMS
- 1.9K Refinitiv Data Platform
- 642 Refinitiv Data Platform Libraries
- 4 LSEG Due Diligence
- LSEG Due Diligence Portal API
- 4 Refinitiv Due Dilligence Centre
- Rose's Space
- 1.2K Screening
- 18 Qual-ID API
- 13 Screening Deployed
- 23 Screening Online
- 12 World-Check Customer Risk Screener
- 1K World-Check One
- 46 World-Check One Zero Footprint
- 45 Side by Side Integration API
- 2 Test Space
- 3 Thomson One Smart
- 10 TR Knowledge Graph
- 151 Transactions
- 143 REDI API
- 1.8K TREP APIs
- 4 CAT
- 26 DACS Station
- 121 Open DACS
- 1.1K RFA
- 104 UPA
- 192 TREP Infrastructure
- 228 TRKD
- 915 TRTH
- 5 Velocity Analytics
- 9 Wealth Management Web Services
- 89 Workspace SDK
- 11 Element Framework
- 5 Grid
- 18 World-Check Data File
- 1 Yield Book Analytics
- 46 中文论坛