com.google.cloud.hadoop.gcsio

Class CacheEntry

java.lang.Object

com.google.cloud.hadoop.gcsio.CacheEntry

Direct Known Subclasses:

CachedBucket

public class CacheEntry
extends Object

Container for various pieces of metadata for a single cache entry, which may be either a Bucket or a StorageObject; includes GCS API metadata such as StorageResourceId and GoogleCloudStorageItemInfo as well as cache-specific metadata, such as creation time, and last-updated time.

Constructor Summary

Constructors

Constructor and Description
CacheEntry(GoogleCloudStorageItemInfo itemInfo)
CacheEntry(StorageResourceId resourceId) Constructs a CacheEntry with no known GoogleCloudStorageItemInfo; callers may have to fetch the associated GoogleCloudStorageItemInfo on-demand.
CacheEntry(StorageResourceId resourceId, long creationTimeMillis) Constructs a CacheEntry with no known GoogleCloudStorageItemInfo and an explicit creationTimeMillis; callers may have to fetch the associated GoogleCloudStorageItemInfo on-demand.

Method Summary

Modifier and Type	Method and Description
void	clearItemInfo() Clears the GoogleCloudStorageItemInfo stored by this CacheEntry, if any, and sets itemInfoUpdateTimeMillis to 0.
long	getCreationTimeMillis() Accessor for the creation-time of this CacheEntry, which was set at construction-time and is immutable.
GoogleCloudStorageItemInfo	getItemInfo() Returns the GoogleCloudStorageItemInfo currently held by this CacheEntry; may be null if one was never provided.
long	getItemInfoUpdateTimeMillis() Accessor for the last time the GoogleCloudStorageItemInfo of this CacheEntry was updated, or 0 if it was never updated.
StorageResourceId	getResourceId() Returns the StorageResourceId associated with this CacheEntry; may identify a Bucket or StorageObject.
static void	setClock(com.google.api.client.util.Clock clock) Sets a custom Clock to be used for computing cache creation and update times.
GoogleCloudStorageItemInfo	setItemInfo(GoogleCloudStorageItemInfo newItemInfo) Sets the GoogleCloudStorageItemInfo corresponding to this CacheEntry's StorageResourceId, and updates the itemInfoUpdateTimeMillis.

Methods inherited from class java.lang.Object

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

Constructor Detail

CacheEntry

public CacheEntry(StorageResourceId resourceId)

Constructs a CacheEntry with no known GoogleCloudStorageItemInfo; callers may have to fetch the associated GoogleCloudStorageItemInfo on-demand.

Parameters:

resourceId - Must be non-null, and correspond to either a Bucket or StorageObject.

CacheEntry

public CacheEntry(StorageResourceId resourceId,
                  long creationTimeMillis)

Constructs a CacheEntry with no known GoogleCloudStorageItemInfo and an explicit creationTimeMillis; callers may have to fetch the associated GoogleCloudStorageItemInfo on-demand. This should be used for implementations where the in-memory CacheEntry objects are not the authoritative listing, and presumably the cache-entry creation times are stored somewhere else, e.g. on a filesystem.

Parameters:

resourceId - Must be non-null, and correspond to either a Bucket or StorageObject.

creationTimeMillis - The logical creation time of the authoritative cache entry.

CacheEntry

public CacheEntry(GoogleCloudStorageItemInfo itemInfo)

Parameters:

itemInfo - A last-known itemInfo associated to be held and returned by this CacheEntry; must be non-null, must be a Bucket or StorageObject, and exists() must return true.

Method Detail

setClock

public static void setClock(com.google.api.client.util.Clock clock)

Sets a custom Clock to be used for computing cache creation and update times.

getResourceId

public StorageResourceId getResourceId()

Returns the StorageResourceId associated with this CacheEntry; may identify a Bucket or StorageObject.

getCreationTimeMillis

public long getCreationTimeMillis()

Accessor for the creation-time of this CacheEntry, which was set at construction-time and is immutable.

getItemInfoUpdateTimeMillis

public long getItemInfoUpdateTimeMillis()

Accessor for the last time the GoogleCloudStorageItemInfo of this CacheEntry was updated, or 0 if it was never updated.

getItemInfo

public GoogleCloudStorageItemInfo getItemInfo()

Returns the GoogleCloudStorageItemInfo currently held by this CacheEntry; may be null if one was never provided.

clearItemInfo

public void clearItemInfo()

Clears the GoogleCloudStorageItemInfo stored by this CacheEntry, if any, and sets itemInfoUpdateTimeMillis to 0.

setItemInfo

public GoogleCloudStorageItemInfo setItemInfo(GoogleCloudStorageItemInfo newItemInfo)

Sets the GoogleCloudStorageItemInfo corresponding to this CacheEntry's StorageResourceId, and updates the itemInfoUpdateTimeMillis. Returns the old info, or null if it was never set before.

Parameters:

newItemInfo - Info corresponding to this entry's Storage resource, must not be null, must not be root, and the info's StorageResourceId must match the existing StorageResourceId of this CacheEntry.