Replacing immutable core API calls
Any typical ActivePivot implementation will define stores using two core API objects, the StoreDescriptionBuilder
and ReferenceDescriptionBuilder
. These objects are followed by a chain of fluent API calls that can be considered immutable - the chain is a complete definition of the store or reference configuration, and any partial (or iterative) definition is difficult due to the nested interfaces composing the fluent API.
The Datastore Helper API makes these fluent API chains mutable, by providing implementations that allow external customisations to be defined using the datastore configurator.
The MutableStoreDescriptionBuilder
and MutableReferenceDescriptionBuilder
objects can be instantiated manually using their public constructors, but using the factory methods provided in the configurator allows for non-breaking future changes in the implementation details of the Datastore Helper API.
A typical migration of an existing project would entail the following modifications.
MutableStoreDescriptionBuilder
The standard store definition
new StoreDescriptionBuilder()
.withStoreName(TRADE_PNL_STORE_NAME)
.withField(AS_OF_DATE, LOCAL_DATE).asKeyField()
.withField(TRADE_PNL__TRADE_ID).asKeyField()
.withField(TRADE_PNL__SCENARIO_SET).asKeyField()
.withField(TRADE_PNL__CALCULATION_ID).asKeyField()
.withField(TRADE_PNL__RISK_FACTOR).asKeyField()
.withField(TRADE_PNL__RISK_CLASS)
.withField(TRADE_PNL__RISK_FACTOR_TYPE)
.withField(TRADE_PNL__LIQUIDITY_HORIZON, INT)
.withField(TRADE_PNL__CCY)
.withVectorField(TRADE_PNL__PNL_VECTOR, DOUBLE)
.withModuloPartitioning(TRADE_PNL__TRADE_ID, NUM_HASH_PARTITIONS)
.onDuplicateKeyWithinTransaction().logException()
.build();
becomes
configurator.storeBuilder(PNL_SCHEMA)
.withStoreName(TRADE_PNL_STORE_NAME)
.withField(AS_OF_DATE, LOCAL_DATE).asKeyField()
.withField(TRADE_PNL__TRADE_ID).asKeyField()
.withField(TRADE_PNL__SCENARIO_SET).asKeyField()
.withField(TRADE_PNL__CALCULATION_ID).asKeyField()
.withField(TRADE_PNL__RISK_FACTOR).asKeyField()
.withField(TRADE_PNL__RISK_CLASS)
.withField(TRADE_PNL__RISK_FACTOR_TYPE)
.withField(TRADE_PNL__LIQUIDITY_HORIZON, INT)
.withField(TRADE_PNL__CCY)
.withVectorField(TRADE_PNL__PNL_VECTOR, DOUBLE)
.withModuloPartitioning(TRADE_PNL__TRADE_ID, NUM_HASH_PARTITIONS)
.onDuplicateKeyWithinTransaction().logException()
.build();
MutableReferenceDescriptionBuilder
The standard reference definition
ReferenceDescription.builder()
.fromStore(COUNTERPARTY_STORE_NAME)
.toStore(COUNTRY_STORE_NAME)
.withName(COUNTERPARTY_TO_COUNTRY_RISK)
.withMapping(COUNTERPARTY__COUNTRY_OF_RISK, COUNTRY__COUNTRY_CODE)
.withMapping(AS_OF_DATE, AS_OF_DATE)
.build();
becomes
configurator.referenceBuilder(PNL_SCHEMA)
.fromStore(COUNTERPARTY_STORE_NAME)
.toStore(COUNTRY_STORE_NAME)
.withName(COUNTERPARTY_TO_COUNTRY_RISK)
.withMapping(COUNTERPARTY__COUNTRY_OF_RISK, COUNTRY__COUNTRY_CODE)
.withMapping(AS_OF_DATE, AS_OF_DATE)
.build();