org.apache.hadoop.hive.metastore.properties

Class PropertyStore

java.lang.Object

org.apache.hadoop.hive.metastore.properties.PropertyStore

Direct Known Subclasses:

CachingPropertyStore

public abstract class PropertyStore
extends Object

The PropertyStore is the persistent container of property maps. Maps are addressed in the store by their key - their name prepended by their manager"s namespace.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PropertyStore() Default ctor.

Method Summary

Modifier and Type	Method and Description
PropertyMap	deserialize(byte[] bytes, Function<String,PropertySchema> getSchema) Deserializes a map from a byte array.
protected abstract boolean	dropProperties(String mapKey) Drops a property map.
abstract UUID	fetchDigest(String mapKey) Fetches a property map digest.
abstract PropertyMap	fetchProperties(String mapKey, Function<String,PropertySchema> getSchema) Fetches a property map.
abstract boolean	renameProperties(String mapKey, String newKey) Renames a property map.
void	saveProperties(Iterator<Map.Entry<String,PropertyMap>> save) Persists an iterator property map.
protected abstract void	saveProperties(String mapKey, PropertyMap map) Persists a property map.
abstract Map<String,UUID>	selectDigest(String keyPrefix, Predicate<String> keyFilter) Fetches a map of property maps digest keyed by their name.
abstract Map<String,PropertyMap>	selectProperties(String keyPrefix, Predicate<String> keyFilter, Function<String,PropertySchema> getSchema) Fetches a map of property maps.
byte[]	serialize(PropertyMap map) Serializes a map as a byte array.

Methods inherited from class java.lang.Object

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

Constructor Detail

PropertyStore

protected PropertyStore()

Default ctor.

Method Detail

fetchProperties

public abstract PropertyMap fetchProperties(String mapKey,
                                            Function<String,PropertySchema> getSchema)

Fetches a property map.

Parameters:

mapKey - the map key

getSchema - the method to retrieve a schema if the map needs to be created

Returns:

the item property map

selectProperties

public abstract Map<String,PropertyMap> selectProperties(String keyPrefix,
                                                         Predicate<String> keyFilter,
                                                         Function<String,PropertySchema> getSchema)

Fetches a map of property maps.

Parameters:

keyPrefix - the map key prefix

keyFilter - a filter for map keys

getSchema - the method to retrieve a schema if the map needs to be created

Returns:

the map of property map

fetchDigest

public abstract UUID fetchDigest(String mapKey)

Fetches a property map digest.

Parameters:

mapKey - the map key

Returns:

the item property map

selectDigest

public abstract Map<String,UUID> selectDigest(String keyPrefix,
                                              Predicate<String> keyFilter)

Fetches a map of property maps digest keyed by their name.

Parameters:

keyPrefix - the map key prefix

keyFilter - a filter for map keys

Returns:

the map of property map digests

saveProperties

protected abstract void saveProperties(String mapKey,
                                       PropertyMap map)

Persists a property map.

Parameters:

mapKey - the map key

map - the map instance

dropProperties

protected abstract boolean dropProperties(String mapKey)

Drops a property map.

Parameters:

mapKey - the map key

renameProperties

public abstract boolean renameProperties(String mapKey,
                                         String newKey)

Renames a property map.

Parameters:

mapKey - the map source key

newKey - the new target key

saveProperties

public void saveProperties(Iterator<Map.Entry<String,PropertyMap>> save)

Persists an iterator property map.

May be useful to override to use one transaction.

Parameters:

save - the iterator on pairs for map key, property map

serialize

public byte[] serialize(PropertyMap map)

Serializes a map as a byte array.

Parameters:

map - the (nonnull) map to write

Returns:

the byte array

deserialize

public PropertyMap deserialize(byte[] bytes,
                               Function<String,PropertySchema> getSchema)

Deserializes a map from a byte array.

Parameters:

bytes - the byte array

Returns:

the (nonnull) property map