Package com.amazonaws.services.dynamodbv2.datamodeling.encryption.providers

Class CachingMostRecentProvider

java.lang.Object

com.amazonaws.services.dynamodbv2.datamodeling.encryption.providers.CachingMostRecentProvider

All Implemented Interfaces:

EncryptionMaterialsProvider

public class CachingMostRecentProvider
extends Object
implements EncryptionMaterialsProvider

This meta-Provider encrypts data with the most recent version of keying materials from a ProviderStore and decrypts using whichever version is appropriate. It also caches the results from the ProviderStore to avoid excessive load on the backing systems.

Field Summary

Fields

Modifier and Type	Field	Description
protected final String	defaultMaterialName

Constructor Summary

Constructors

Constructor	Description
CachingMostRecentProvider(ProviderStore keystore, String materialName, long ttlInMillis)	Creates a new CachingMostRecentProvider.
CachingMostRecentProvider(ProviderStore keystore, String materialName, long ttlInMillis, int maxCacheSize)	Creates a new CachingMostRecentProvider.

Method Summary

Modifier and Type	Method	Description
long	getCurrentVersion()	The current version of the materials being used for encryption.
DecryptionMaterials	getDecryptionMaterials(EncryptionContext context)	Retrieves encryption materials matching the specified description from some source.
EncryptionMaterials	getEncryptionMaterials(EncryptionContext context)	Returns EncryptionMaterials which the caller can use for encryption.
long	getLastUpdated()	The last time the current version was updated.
String	getMaterialName()
protected String	getMaterialName(EncryptionContext context)
long	getTtlInMills()
void	refresh()	Completely empties the cache of both the current and old versions.

Methods inherited from class java.lang.Object

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

Field Details

defaultMaterialName

protected final String defaultMaterialName

Constructor Details

CachingMostRecentProvider

public CachingMostRecentProvider(ProviderStore keystore,
 String materialName,
 long ttlInMillis)

Creates a new CachingMostRecentProvider.

Parameters:

keystore - The key store that this provider will use to determine which material and which version of material to use

materialName - The name of the materials associated with this provider

ttlInMillis - The length of time in milliseconds to cache the most recent provider

CachingMostRecentProvider

public CachingMostRecentProvider(ProviderStore keystore,
 String materialName,
 long ttlInMillis,
 int maxCacheSize)

Creates a new CachingMostRecentProvider.

Parameters:

keystore - The key store that this provider will use to determine which material and which version of material to use

materialName - The name of the materials associated with this provider

ttlInMillis - The length of time in milliseconds to cache the most recent provider

maxCacheSize - The maximum size of the underlying caches this provider uses. Entries will be evicted from the cache once this size is exceeded.

Method Details

getEncryptionMaterials

public EncryptionMaterials getEncryptionMaterials(EncryptionContext context)

Description copied from interface: EncryptionMaterialsProvider

Returns EncryptionMaterials which the caller can use for encryption. Each implementation of EncryptionMaterialsProvider can choose its own strategy for loading encryption material. For example, an implementation might load encryption material from an existing key management system, or load new encryption material when keys are rotated.

Specified by:

getEncryptionMaterials in interface EncryptionMaterialsProvider

Parameters:

context - Information to assist in selecting a the proper return value. The implementation is free to determine the minimum necessary for successful processing.

Returns:

EncryptionMaterials which the caller can use to encrypt or decrypt data.

getDecryptionMaterials

public DecryptionMaterials getDecryptionMaterials(EncryptionContext context)

Description copied from interface: EncryptionMaterialsProvider

Retrieves encryption materials matching the specified description from some source.

Specified by:

getDecryptionMaterials in interface EncryptionMaterialsProvider

Parameters:

context - Information to assist in selecting a the proper return value. The implementation is free to determine the minimum necessary for successful processing.

Returns:

The encryption materials that match the description, or null if no matching encryption materials found.

refresh

public void refresh()

Completely empties the cache of both the current and old versions.

Specified by:

refresh in interface EncryptionMaterialsProvider

getMaterialName

public String getMaterialName()

getTtlInMills

public long getTtlInMills()

getCurrentVersion

public long getCurrentVersion()

The current version of the materials being used for encryption. Returns -1 if we do not currently have a current version.

getLastUpdated

public long getLastUpdated()

The last time the current version was updated. Returns 0 if we do not currently have a current version.

getMaterialName

protected String getMaterialName(EncryptionContext context)