io.druid.server.lookup.namespace

Class JDBCExtractionNamespaceCacheFactory

java.lang.Object

io.druid.server.lookup.namespace.JDBCExtractionNamespaceCacheFactory

All Implemented Interfaces:

ExtractionNamespaceCacheFactory<JDBCExtractionNamespace>

public class JDBCExtractionNamespaceCacheFactory
extends Object
implements ExtractionNamespaceCacheFactory<JDBCExtractionNamespace>

Constructor Summary

Constructors

Constructor and Description
JDBCExtractionNamespaceCacheFactory()

Method Summary

Modifier and Type

Method and Description

Callable<String>

getCachePopulator(String id, JDBCExtractionNamespace namespace, String lastVersion, Map<String,String> cache) This function is called once if `ExtractionNamespace.getUpdateMs() == 0`, or every update if `ExtractionNamespace.getUpdateMs() > 0` For ExtractionNamespace which have the NamespaceExtractionCacheManager handle regular updates, this function is used to populate the namespace cache each time.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

JDBCExtractionNamespaceCacheFactory

public JDBCExtractionNamespaceCacheFactory()

Method Detail

getCachePopulator

public Callable<String> getCachePopulator(String id,
                                          JDBCExtractionNamespace namespace,
                                          String lastVersion,
                                          Map<String,String> cache)

Description copied from interface: ExtractionNamespaceCacheFactory

This function is called once if `ExtractionNamespace.getUpdateMs() == 0`, or every update if `ExtractionNamespace.getUpdateMs() > 0` For ExtractionNamespace which have the NamespaceExtractionCacheManager handle regular updates, this function is used to populate the namespace cache each time. For ExtractionNamespace implementations which do not have regular updates, this function can be used to initialize resources. If the result of the Callable is the same as what is passed in as lastVersion, then no swap takes place, and the swap is discarded.

Specified by:

getCachePopulator in interface ExtractionNamespaceCacheFactory<JDBCExtractionNamespace>

Parameters:

id - The ID of ExtractionNamespace

namespace - The ExtractionNamespace for which to populate data.

lastVersion - The version which was last cached

cache - The temporary Map into which data may be placed and will be "swapped" with the proper namespace Map in NamespaceExtractionCacheManager. Implementations which cannot offer a swappable cache of the data may ignore this but must make sure `buildFn(...)` returns a proper Function.

Returns:

A callable that will be used to refresh resources of the namespace and return the version string used in the populating