org.apache.nifi.distributed.cache.client

Interface DistributedSetCacheClient

All Superinterfaces:

ConfigurableComponent, ControllerService

@Tags(value={"distributed","client","cluster","set","cache"})
 @CapabilityDescription(value="Provides the ability to communicate with a DistributedSetCacheServer. This allows multiple nodes to coordinate state with a single remote entity.")
public interface DistributedSetCacheClient
extends ControllerService

This interface defines an API that can be used for interacting with a Distributed Cache that functions similarly to a Set.

Method Summary

Modifier and Type	Method and Description
<T> boolean	addIfAbsent(T value, Serializer<T> serializer) Adds the specified value to the cache, serializing the value with the given Serializer.
void	close() Attempts to notify the server that we are finished communicating with it and cleans up resources
<T> boolean	contains(T value, Serializer<T> serializer)
<T> boolean	remove(T value, Serializer<T> serializer) Removes the given value from the cache, if it is present.

Methods inherited from interface org.apache.nifi.controller.ControllerService

initialize, isStateful

Methods inherited from interface org.apache.nifi.components.ConfigurableComponent

getIdentifier, getPropertyDescriptor, getPropertyDescriptors, onPropertyModified, validate

Method Detail

addIfAbsent

<T> boolean addIfAbsent(T value,
                        Serializer<T> serializer)
                 throws IOException

Adds the specified value to the cache, serializing the value with the given Serializer.

Type Parameters:

T - type

Parameters:

value - value

serializer - serializer

Returns:

true if the value was added to the cache, false if the value already existed in the cache

Throws:

IOException - if unable to communicate with the remote instance

contains

<T> boolean contains(T value,
                     Serializer<T> serializer)
              throws IOException

Type Parameters:

T - type

Parameters:

value - value

serializer - serializer

Returns:

if the given value is present in the cache and if so returns true, else returns false

Throws:

IOException - if unable to communicate with the remote instance

remove

<T> boolean remove(T value,
                   Serializer<T> serializer)
            throws IOException

Removes the given value from the cache, if it is present.

Type Parameters:

T - type

Parameters:

value - value

serializer - serializer

Returns:

true if the value is removed, false if the value did not exist in the cache

Throws:

IOException - ex

close

void close()
    throws IOException

Attempts to notify the server that we are finished communicating with it and cleans up resources

Throws:

IOException - ex