ome.smuggler.core.service.file.impl

Class TSafeKeyValueStore<K extends util.object.Identifiable,V>

java.lang.Object

ome.smuggler.core.service.file.impl.TSafeKeyValueStore<K,V>

All Implemented Interfaces:

KeyValueStore<K,V>

public class TSafeKeyValueStore<K extends util.object.Identifiable,V>
extends java.lang.Object
implements KeyValueStore<K,V>

Wraps a KeyValueStore to make it thread safe. This class uses lock striping to serialise operations on the same key while at the same time allowing operations on different keys to run in parallel.

Constructor Summary

Constructors

Constructor and Description
TSafeKeyValueStore(KeyValueStore<K,V> target, PositiveN numberOfStripes) Creates a new instance to add thread-safety to the underlying KeyValueStore.

Method Summary

Modifier and Type	Method and Description
protected java.util.concurrent.locks.Lock	lookupLock(K key)
void	modify(K key, java.util.function.Function<V,V> operation) Updates the value associated to the specified key.
void	put(K key, V value) Maps a key to a value.
void	remove(K key) Deletes the mapping identified by the specified key.
protected void	withLock(K key, java.lang.Runnable action)

Methods inherited from class java.lang.Object

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

Methods inherited from interface ome.smuggler.core.service.file.KeyValueStore

get

Constructor Detail

TSafeKeyValueStore

public TSafeKeyValueStore(KeyValueStore<K,V> target,
                          PositiveN numberOfStripes)

Creates a new instance to add thread-safety to the underlying KeyValueStore.

Parameters:

target - the underlying object providing the functionality.

numberOfStripes - how many locks to use for striping.

Throws:

java.lang.NullPointerException - if any argument is null.

Method Detail

lookupLock

protected java.util.concurrent.locks.Lock lookupLock(K key)

withLock

protected void withLock(K key,
                        java.lang.Runnable action)

put

public void put(K key,
                V value)

Description copied from interface: KeyValueStore

Maps a key to a value. If the specified key is already associated to a value, the old value will be overwritten.

Specified by:

put in interface KeyValueStore<K extends util.object.Identifiable,V>

Parameters:

key - identifies the mapping.

value - the value to store.

modify

public void modify(K key,
                   java.util.function.Function<V,V> operation)

Description copied from interface: KeyValueStore

Updates the value associated to the specified key.

Specified by:

modify in interface KeyValueStore<K extends util.object.Identifiable,V>

Parameters:

key - identifies the mapping.

operation - is given the current value, does something with it and then returns the new value.

remove

public void remove(K key)

Description copied from interface: KeyValueStore

Deletes the mapping identified by the specified key. Does nothing if no value is currently associated to the key.

Specified by:

remove in interface KeyValueStore<K extends util.object.Identifiable,V>

Parameters:

key - identifies the mapping.