Package org.apache.pulsar.metadata.cache.impl

Class MetadataCacheImpl<T>

java.lang.Object

org.apache.pulsar.metadata.cache.impl.MetadataCacheImpl<T>

All Implemented Interfaces:

Consumer<Notification>, MetadataCache<T>

public class MetadataCacheImpl<T>
extends Object
implements MetadataCache<T>, Consumer<Notification>

Constructor Summary

Constructors

Constructor	Description
MetadataCacheImpl(MetadataStore store, com.fasterxml.jackson.core.type.TypeReference<T> typeRef, MetadataCacheConfig cacheConfig)
MetadataCacheImpl(MetadataStore store, com.fasterxml.jackson.databind.JavaType type, MetadataCacheConfig cacheConfig)
MetadataCacheImpl(MetadataStore store, MetadataSerde<T> serde, MetadataCacheConfig cacheConfig)

Method Summary

Modifier and Type	Method	Description
void	accept(Notification t)
CompletableFuture<Void>	create(String path, T value)	Create a new object in the metadata store.
CompletableFuture<Void>	delete(String path)	Delete an object from the metadata store.
CompletableFuture<Boolean>	exists(String path)	Read whether a specific path exists.
CompletableFuture<Optional<T>>	get(String path)	Tries to fetch one item from the cache or fallback to the store if not present.
CompletableFuture<List<String>>	getChildren(String path)	Return all the nodes (lexicographically sorted) that are children to the specific path.
Optional<T>	getIfCached(String path)	Check if an object is present in cache without triggering a load from the metadata store.
CompletableFuture<Optional<CacheGetResult<T>>>	getWithStats(String path)	Tries to fetch one item from the cache or fallback to the store if not present.
void	invalidate(String path)	Force the invalidation of an object in the metadata cache.
void	invalidateAll()
CompletableFuture<T>	readModifyUpdate(String path, Function<T,T> modifyFunction)	Perform an atomic read-modify-update of the value.
CompletableFuture<T>	readModifyUpdateOrCreate(String path, Function<Optional<T>,T> modifyFunction)	Perform an atomic read-modify-update of the value.
void	refresh(String path)	Invalidate and reload an object in the metadata cache.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.function.Consumer

andThen

Constructor Details

MetadataCacheImpl

public MetadataCacheImpl(MetadataStore store,
 com.fasterxml.jackson.core.type.TypeReference<T> typeRef,
 MetadataCacheConfig cacheConfig)

MetadataCacheImpl

public MetadataCacheImpl(MetadataStore store,
 com.fasterxml.jackson.databind.JavaType type,
 MetadataCacheConfig cacheConfig)

MetadataCacheImpl

public MetadataCacheImpl(MetadataStore store,
 MetadataSerde<T> serde,
 MetadataCacheConfig cacheConfig)

Method Details

get

public CompletableFuture<Optional<T>> get(String path)

Description copied from interface: MetadataCache

Tries to fetch one item from the cache or fallback to the store if not present.

If the key is not found, the Optional will be empty.

Specified by:

get in interface MetadataCache<T>

Parameters:

path - the path of the object in the metadata store

Returns:

a future to track the completion of the operation

getWithStats

public CompletableFuture<Optional<CacheGetResult<T>>> getWithStats(String path)

Description copied from interface: MetadataCache

Tries to fetch one item from the cache or fallback to the store if not present.

If the key is not found, the Optional will be empty.

Specified by:

getWithStats in interface MetadataCache<T>

Parameters:

path - the path of the object in the metadata store

Returns:

a future to track the completion of the operation

getIfCached

public Optional<T> getIfCached(String path)

Description copied from interface: MetadataCache

Check if an object is present in cache without triggering a load from the metadata store.

Specified by:

getIfCached in interface MetadataCache<T>

Parameters:

path - the path of the object in the metadata store

Returns:

the cached object or an empty Optional is the cache doesn't have the object

readModifyUpdateOrCreate

public CompletableFuture<T> readModifyUpdateOrCreate(String path,
 Function<Optional<T>,T> modifyFunction)

Description copied from interface: MetadataCache

Perform an atomic read-modify-update of the value.

The modify function can potentially be called multiple times if there are concurrent updates happening.

If the object does not exist yet, the modifyFunction will get passed an Optional.empty() object.

Specified by:

readModifyUpdateOrCreate in interface MetadataCache<T>

Parameters:

path - the path of the object in the metadata store

modifyFunction - a function that will be passed the current value and returns a modified value to be stored

Returns:

a future to track the completion of the operation

readModifyUpdate

public CompletableFuture<T> readModifyUpdate(String path,
 Function<T,T> modifyFunction)

Description copied from interface: MetadataCache

Perform an atomic read-modify-update of the value.

The modify function can potentially be called multiple times if there are concurrent updates happening.

Specified by:

readModifyUpdate in interface MetadataCache<T>

Parameters:

path - the path of the object in the metadata store

modifyFunction - a function that will be passed the current value and returns a modified value to be stored

Returns:

a future to track the completion of the operation

create

public CompletableFuture<Void> create(String path,
 T value)

Description copied from interface: MetadataCache

Create a new object in the metadata store.

This operation will make sure to keep the cache consistent.

Specified by:

create in interface MetadataCache<T>

Parameters:

path - the path of the object in the metadata store

value - the object to insert in metadata store

Returns:

a future to track the completion of the operation

delete

public CompletableFuture<Void> delete(String path)

Description copied from interface: MetadataCache

Delete an object from the metadata store.

This operation will make sure to keep the cache consistent.

Specified by:

delete in interface MetadataCache<T>

Parameters:

path - the path of the object in the metadata store

Returns:

a future to track the completion of the operation

exists

public CompletableFuture<Boolean> exists(String path)

Description copied from interface: MetadataCache

Read whether a specific path exists. Note: In case of keys with multiple levels (eg: '/a/b/c'), checking the existence of a parent (eg. '/a') might not necessarily return true, unless the key had been explicitly created.

Specified by:

exists in interface MetadataCache<T>

Parameters:

path - the path of the key to check on the store

Returns:

a future to track the async request

getChildren

public CompletableFuture<List<String>> getChildren(String path)

Description copied from interface: MetadataCache

Return all the nodes (lexicographically sorted) that are children to the specific path. If the path itself does not exist, it will return an empty list.

Specified by:

getChildren in interface MetadataCache<T>

Parameters:

path - the path of the key to get from the store

Returns:

a future to track the async request

invalidate

public void invalidate(String path)

Description copied from interface: MetadataCache

Force the invalidation of an object in the metadata cache.

Specified by:

invalidate in interface MetadataCache<T>

Parameters:

path - the path of the object in the metadata store

refresh

public void refresh(String path)

Description copied from interface: MetadataCache

Invalidate and reload an object in the metadata cache.

Specified by:

refresh in interface MetadataCache<T>

Parameters:

path - the path of the object in the metadata store

invalidateAll

public void invalidateAll()

accept

public void accept(Notification t)

Specified by:

accept in interface Consumer<T>