org.apache.hadoop.fs.azurebfs.services

Class AbfsLease

java.lang.Object

org.apache.hadoop.fs.azurebfs.services.AbfsLease

public final class AbfsLease
extends Object

AbfsLease manages an Azure blob lease. It acquires an infinite lease on instantiation and releases the lease when free() is called. Use it to prevent writes to the blob by other processes that don't have the lease. Creating a new Lease object blocks the caller until the Azure blob lease is acquired. It will retry a fixed number of times before failing if there is a problem acquiring the lease. Call free() to release the Lease. If the holder process dies, AzureBlobFileSystem breakLease will need to be called before another client will be able to write to the file.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AbfsLease.LeaseException

Constructor Summary

Constructors

Constructor and Description
AbfsLease(AbfsClient client, String path, int acquireMaxRetries, int acquireRetryInterval, TracingContext tracingContext)
AbfsLease(AbfsClient client, String path, TracingContext tracingContext)

Method Summary

Modifier and Type	Method and Description
void	free() Cancel future and free the lease.
int	getAcquireRetryCount()
String	getLeaseID()
TracingContext	getTracingContext()
boolean	isFreed()

Methods inherited from class java.lang.Object

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

Constructor Detail

AbfsLease

public AbfsLease(AbfsClient client,
                 String path,
                 TracingContext tracingContext)
          throws AzureBlobFileSystemException

Throws:

AzureBlobFileSystemException

AbfsLease

@VisibleForTesting
public AbfsLease(AbfsClient client,
                                    String path,
                                    int acquireMaxRetries,
                                    int acquireRetryInterval,
                                    TracingContext tracingContext)
                             throws AzureBlobFileSystemException

Throws:

AzureBlobFileSystemException

Method Detail

free

public void free()

Cancel future and free the lease. If an exception occurs while releasing the lease, the error will be logged. If the lease cannot be released, AzureBlobFileSystem breakLease will need to be called before another client will be able to write to the file.

isFreed

public boolean isFreed()

getLeaseID

public String getLeaseID()

getAcquireRetryCount

@VisibleForTesting
public int getAcquireRetryCount()

getTracingContext

@VisibleForTesting
public TracingContext getTracingContext()