Package ca.uhn.fhir.jpa.util

Class MemoryCacheService

java.lang.Object

ca.uhn.fhir.jpa.util.MemoryCacheService

public class MemoryCacheService
extends Object

This class acts as a central spot for all of the many Caffeine caches we use in HAPI FHIR.

The API is super simplistic, and caches are all 1-minute, max 10000 entries for starters. We could definitely add nuance to this, which will be much easier now that this is being centralized. Some logging/monitoring would be good too.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	MemoryCacheService.CacheEnum
static class	MemoryCacheService.HistoryCountKey
static class	MemoryCacheService.TagDefinitionCacheKey

Constructor Summary

Constructors

Constructor	Description
MemoryCacheService(JpaStorageSettings theStorageSettings)

Method Summary

Modifier and Type	Method	Description
protected <K, T> T	doGet(MemoryCacheService.CacheEnum theCache, K theKey, Function<K,T> theSupplier)
protected <K, V> Map<K,V>	doGetAllPresent(MemoryCacheService.CacheEnum theCache, Collection<K> theKeys)
protected <K, V> V	doGetIfPresent(MemoryCacheService.CacheEnum theCache, K theKey)
protected <K, V> void	doPut(MemoryCacheService.CacheEnum theCache, K theKey, V theValue)
<K, T> T	get(MemoryCacheService.CacheEnum theCache, K theKey, Function<K,T> theSupplier)
<K, V> Map<K,V>	getAllPresent(MemoryCacheService.CacheEnum theCache, Collection<K> theKeys)
long	getEstimatedSize(MemoryCacheService.CacheEnum theCache)
<K, V> V	getIfPresent(MemoryCacheService.CacheEnum theCache, K theKey)
<K, T> T	getThenPutAfterCommit(MemoryCacheService.CacheEnum theCache, K theKey, Function<K,T> theSupplier)	Fetch an item from the cache if it exists, and use the loading function to obtain it otherwise.
void	invalidateAllCaches()
void	invalidateCaches(MemoryCacheService.CacheEnum... theCaches)
<K, V> void	put(MemoryCacheService.CacheEnum theCache, K theKey, V theValue)
<K, V> void	putAfterCommit(MemoryCacheService.CacheEnum theCache, K theKey, V theValue)	This method registers a transaction synchronization that puts an entry in the cache if and when the current database transaction successfully commits.

Methods inherited from class java.lang.Object

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

Constructor Details

MemoryCacheService

public MemoryCacheService(JpaStorageSettings theStorageSettings)

Method Details

get

public <K,
T> T get(MemoryCacheService.CacheEnum theCache,
 K theKey,
 Function<K,T> theSupplier)

doGet

protected <K,
T> T doGet(MemoryCacheService.CacheEnum theCache,
 K theKey,
 Function<K,T> theSupplier)

getThenPutAfterCommit

public <K,
T> T getThenPutAfterCommit(MemoryCacheService.CacheEnum theCache,
 K theKey,
 Function<K,T> theSupplier)

Fetch an item from the cache if it exists, and use the loading function to obtain it otherwise.

This method will put the value into the cache using putAfterCommit(CacheEnum, Object, Object).

getIfPresent

public <K,
V> V getIfPresent(MemoryCacheService.CacheEnum theCache,
 K theKey)

doGetIfPresent

protected <K,
V> V doGetIfPresent(MemoryCacheService.CacheEnum theCache,
 K theKey)

put

public <K,
V> void put(MemoryCacheService.CacheEnum theCache,
 K theKey,
 V theValue)

doPut

protected <K,
V> void doPut(MemoryCacheService.CacheEnum theCache,
 K theKey,
 V theValue)

putAfterCommit

public <K,
V> void putAfterCommit(MemoryCacheService.CacheEnum theCache,
 K theKey,
 V theValue)

This method registers a transaction synchronization that puts an entry in the cache if and when the current database transaction successfully commits. If the transaction is rolled back, the key+value passed into this method will not be added to the cache.

This is useful for situations where you want to store something that has been resolved in the DB during the current transaction, but it's not yet guaranteed that this item will successfully save to the DB. Use this method in that case in order to avoid cache poisoning.

getAllPresent

public <K,
V> Map<K,V> getAllPresent(MemoryCacheService.CacheEnum theCache,
 Collection<K> theKeys)

doGetAllPresent

protected <K,
V> Map<K,V> doGetAllPresent(MemoryCacheService.CacheEnum theCache,
 Collection<K> theKeys)

invalidateAllCaches

public void invalidateAllCaches()

getEstimatedSize

public long getEstimatedSize(MemoryCacheService.CacheEnum theCache)

invalidateCaches

public void invalidateCaches(MemoryCacheService.CacheEnum... theCaches)