com.linkedin.paldb.impl

Class StorageCache

java.lang.Object

com.linkedin.paldb.impl.StorageCache

public class StorageCache
extends java.lang.Object

LRU cache configured on the desired size in memory.

This cache can be configured with the following properties:

cache.enabled - LRU cache enabled

cache.bytes - cache limit (bytes)

cache.initial.capacity - cache initial capacity

cache.load.factor - cache load factor

The cache estimates the size of the objects it contains so it consumes no more than the configured memory limit.

Field Summary

Fields

Modifier and Type	Field and Description
protected static java.lang.Object	NULL_VALUE

Method Summary

Modifier and Type	Method and Description
boolean	contains(java.lang.Object key) Returns true if the cache contains key.
<K> K	get(java.lang.Object key) Gets the value in the cache for key or null if not found.
long	getWeight() Gets the cache current weight.
void	put(java.lang.Object key, java.lang.Object value) Puts the key/value pair into the cache.
void	setMaxWeight(long maxWeight) Sets the max weight in the cache.
int	size() Gets the cache size.

Methods inherited from class java.lang.Object

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

Field Detail

NULL_VALUE

protected static final java.lang.Object NULL_VALUE

Method Detail

get

public <K> K get(java.lang.Object key)

Gets the value in the cache for key or null if not found.

If the value associated with key exists but is null, returns StorageCache.NULL_VALUE.

Type Parameters:

K - return type

Parameters:

key - key to get value for

Returns:

value, null or StorageCache.NULL_VALUE

contains

public boolean contains(java.lang.Object key)

Returns true if the cache contains key.

Parameters:

key - key to test presence for

Returns:

true if found, false otherwise

put

public void put(java.lang.Object key,
                java.lang.Object value)

Puts the key/value pair into the cache.

Parameters:

key - key

value - value

setMaxWeight

public void setMaxWeight(long maxWeight)

Sets the max weight in the cache.

Parameters:

maxWeight - max weight

size

public int size()

Gets the cache size.

Returns:

cache size

getWeight

public long getWeight()

Gets the cache current weight.

Returns:

weight