Class Cache

java.lang.Object

de.odysseus.el.tree.impl.Cache

All Implemented Interfaces:

TreeCache

public final class Cache
extends Object
implements TreeCache

Concurrent (thread-safe) FIFO tree cache (using classes from java.util.concurrent). After the cache size reached a certain limit, some least recently used entry are removed, when adding a new entry.

Field Summary

Fields

Modifier and Type	Field	Description
private final int	capacity
private final ConcurrentMap<String,Tree>	map
private final ConcurrentLinkedQueue<String>	queue
private final AtomicInteger	size

Constructor Summary

Constructors

Constructor	Description
Cache(int capacity)	Creates a new cache with the specified capacity and default concurrency level (16).
Cache(int capacity, int concurrencyLevel)	Creates a new cache with the specified capacity and concurrency level.

Method Summary

Modifier and Type	Method	Description
Tree	get(String expression)	Lookup tree
void	put(String expression, Tree tree)	Cache tree
int	size()

Methods inherited from class Object

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

Field Details

map

private final ConcurrentMap<String,Tree> map

queue

private final ConcurrentLinkedQueue<String> queue

size

private final AtomicInteger size

capacity

private final int capacity

Constructor Details

Cache

public Cache(int capacity)

Creates a new cache with the specified capacity and default concurrency level (16).

Parameters:

capacity - Cache size. The actual size may exceed it temporarily.

Cache

public Cache(int capacity,
 int concurrencyLevel)

Creates a new cache with the specified capacity and concurrency level.

Parameters:

capacity - Cache size. The actual map size may exceed it temporarily.

concurrencyLevel - The estimated number of concurrently updating threads. The implementation performs internal sizing to try to accommodate this many threads.

Method Details

size

public int size()

get

public Tree get(String expression)

Description copied from interface: TreeCache

Lookup tree

Specified by:

get in interface TreeCache

put

public void put(String expression,
 Tree tree)

Description copied from interface: TreeCache

Cache tree

Specified by:

put in interface TreeCache