@InterfaceAudience.Public @InterfaceStability.Unstable public abstract class SharedCacheClient extends AbstractService
Constructor and Description |
---|
SharedCacheClient(String name) |
Modifier and Type | Method and Description |
---|---|
static SharedCacheClient |
createSharedCacheClient() |
abstract String |
getFileChecksum(Path sourceFile)
A convenience method to calculate the checksum of a specified file.
|
abstract void |
release(ApplicationId applicationId,
String resourceKey)
The method to release a resource with the
SharedCacheManager.
This method is called once an application is no longer using a claimed
resource in the shared cache. |
abstract URL |
use(ApplicationId applicationId,
String resourceKey)
The method to claim a resource with the
SharedCacheManager.
The client uses a checksum to identify the resource and an
ApplicationId to identify which application will be using the
resource. |
close, getBlockers, getConfig, getFailureCause, getFailureState, getLifecycleHistory, getName, getServiceState, getStartTime, init, isInState, noteFailure, putBlocker, registerGlobalListener, registerServiceListener, removeBlocker, serviceInit, serviceStart, serviceStop, setConfig, start, stop, toString, unregisterGlobalListener, unregisterServiceListener, waitForServiceToStop
@InterfaceAudience.Private public SharedCacheClient(String name)
@InterfaceAudience.Public public static SharedCacheClient createSharedCacheClient()
@InterfaceAudience.Public @InterfaceStability.Unstable public abstract URL use(ApplicationId applicationId, String resourceKey) throws YarnException
The method to claim a resource with the SharedCacheManager.
The client uses a checksum to identify the resource and an
ApplicationId
to identify which application will be using the
resource.
The SharedCacheManager
responds with whether or not the
resource exists in the cache. If the resource exists, a URL
to
the resource in the shared cache is returned. If the resource does not
exist, null is returned instead.
Once a URL has been returned for a resource, that URL is safe to use for the lifetime of the application that corresponds to the provided ApplicationId.
applicationId
- ApplicationId of the application using the resourceresourceKey
- the key (i.e. checksum) that identifies the resourceYarnException
@InterfaceAudience.Public @InterfaceStability.Unstable public abstract void release(ApplicationId applicationId, String resourceKey) throws YarnException
The method to release a resource with the SharedCacheManager.
This method is called once an application is no longer using a claimed
resource in the shared cache. The client uses a checksum to identify the
resource and an ApplicationId
to identify which application is
releasing the resource.
Note: This method is an optimization and the client is not required to call it for correctness.
applicationId
- ApplicationId of the application releasing the
resourceresourceKey
- the key (i.e. checksum) that identifies the resourceYarnException
@InterfaceAudience.Public @InterfaceStability.Unstable public abstract String getFileChecksum(Path sourceFile) throws IOException
sourceFile
- A path to the input fileIOException
Copyright © 2019 Apache Software Foundation. All rights reserved.