org.tinygroup.jspengine.appserv.util.cache
类 LruCache

java.lang.Object
  org.tinygroup.jspengine.appserv.util.cache.BaseCache
      org.tinygroup.jspengine.appserv.util.cache.LruCache

所有已实现的接口：

Cache

public class LruCache
extends BaseCache

LRUCache in-memory bounded cache with an LRU list

嵌套类摘要

protected static class

LruCache.LruCacheItem default CacheItem class implementation

从类 org.tinygroup.jspengine.appserv.util.cache.BaseCache 继承的嵌套类/接口

BaseCache.CacheItem

字段摘要

protected int	defaultMaxEntries
protected LruCache.LruCacheItem	head
protected boolean	isUnbounded
protected int	listSize
static long	NO_TIMEOUT
protected LruCache.LruCacheItem	tail
protected long	timeout
protected int	trimCount

从类 org.tinygroup.jspengine.appserv.util.cache.BaseCache 继承的字段

_rb, bucketLocks, buckets, entryCount, listeners, maxBuckets, refreshFlags, threshold

构造方法摘要

LruCache()
default constructor

LruCache(int defaultMaxEntries)
constructor with specified max entries.

方法摘要

protected BaseCache.CacheItem	createItem(int hashCode, Object key, Object value, int size) create new item
Object	getStatByName(String key) get the desired statistic counter
Map	getStats() get the stats snapshot
void	init(int maxEntries, long timeout, float loadFactor, Properties props) initialize the cache
protected void	itemAccessed(BaseCache.CacheItem item) this item is accessed
protected BaseCache.CacheItem	itemAdded(BaseCache.CacheItem item) /** this item is just added to the cache
protected void	itemRefreshed(BaseCache.CacheItem item, int oldSize) item value has been refreshed
protected void	itemRemoved(BaseCache.CacheItem item) item value has been removed from the cache
void	setTimeout(long timeout) sets the timeout value
void	trimExpiredEntries(int maxCount) trim the expired entries from the cache.
protected BaseCache.CacheItem	trimLru(long currentTime) trim one item from the LRU list

从类 org.tinygroup.jspengine.appserv.util.cache.BaseCache 继承的方法

_put, _remove, _removeItem, add, add, addCacheListener, clear, clearStats, contains, decrementEntryCount, destroy, elements, eq, get, get, getAll, getEntryCount, getIndex, getIndex, handleOverflow, hash, incrementAddCount, incrementEntryCount, incrementHitCount, incrementMissCount, incrementOverflowCount, incrementRefreshCount, incrementRemovalCount, init, init, isEmpty, isThresholdReached, keys, loadValue, notifyRefresh, put, put, remove, remove, remove, removeAll, trimItem, values, waitRefresh

从类 java.lang.Object 继承的方法

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

字段详细信息

NO_TIMEOUT

public static final long NO_TIMEOUT

另请参见：

常量字段值

head

protected LruCache.LruCacheItem head

tail

protected LruCache.LruCacheItem tail

trimCount

protected int trimCount

listSize

protected int listSize

timeout

protected long timeout

defaultMaxEntries

protected int defaultMaxEntries

isUnbounded

protected boolean isUnbounded

构造方法详细信息

LruCache

public LruCache()

default constructor

LruCache

public LruCache(int defaultMaxEntries)

constructor with specified max entries.

参数：

defaultMaxEntries - specifies the default max entries to use when the maxEntries is <= 0.

方法详细信息

init

public void init(int maxEntries,
                 long timeout,
                 float loadFactor,
                 Properties props)

initialize the cache

参数：

maxEntries - maximum number of entries expected in the cache

loadFactor - the load factor

timeout - to be used to trim the expired entries

props - opaque list of properties for a given cache implementation

抛出：

a - generic Exception if the initialization failed

setTimeout

public void setTimeout(long timeout)

sets the timeout value

参数：

timeout - to be used to trim the expired entries

createItem

protected BaseCache.CacheItem createItem(int hashCode,
                                         Object key,
                                         Object value,
                                         int size)

create new item

覆盖：

类 BaseCache 中的 createItem

参数：

hashCode - for the entry

key - Object key

value - Object value

size - size in bytes of the item subclasses may override to provide their own CacheItem extensions e.g. one that permits persistence.

trimLru

protected BaseCache.CacheItem trimLru(long currentTime)

trim one item from the LRU list

参数：

currentTime - of this operation

返回：

the item trimmed from cache list synchronization is handled by the caller

itemAdded

protected BaseCache.CacheItem itemAdded(BaseCache.CacheItem item)

/** this item is just added to the cache

覆盖：

类 BaseCache 中的 itemAdded

参数：

item - CacheItem that was created

返回：

a overflow item; may be null this function checks if adding the new item results in a overflow; if so, it returns the item to be removed. Cache bucket is already synchronized by the caller

itemAccessed

protected void itemAccessed(BaseCache.CacheItem item)

this item is accessed

覆盖：

类 BaseCache 中的 itemAccessed

参数：

item - CacheItem accessed Cache bucket is already synchronized by the caller

itemRefreshed

protected void itemRefreshed(BaseCache.CacheItem item,
                             int oldSize)

item value has been refreshed

覆盖：

类 BaseCache 中的 itemRefreshed

参数：

item - CacheItem that was refreshed

oldSize - size of the previous value that was refreshed Cache bucket is already synchronized by the caller

itemRemoved

protected void itemRemoved(BaseCache.CacheItem item)

item value has been removed from the cache

覆盖：

类 BaseCache 中的 itemRemoved

参数：

item - CacheItem that was just removed Cache bucket is already synchronized by the caller

trimExpiredEntries

public void trimExpiredEntries(int maxCount)

trim the expired entries from the cache.

指定者：

接口 Cache 中的 trimExpiredEntries

覆盖：

类 BaseCache 中的 trimExpiredEntries

参数：

maxCount - maximum number of invalid entries to trim specify Integer.MAX_VALUE to trim all invalid entries This call is to be scheduled by a thread managed by the container. NOTE: this algorithm assumes that all the entries in the cache have identical timeout (otherwise traversing from tail won't be right).

getStatByName

public Object getStatByName(String key)

get the desired statistic counter

指定者：

接口 Cache 中的 getStatByName

覆盖：

类 BaseCache 中的 getStatByName

参数：

key - to corresponding stat

返回：

an Object corresponding to the stat See also: Constant.java for the key

getStats

public Map getStats()

从类 BaseCache 复制的描述

get the stats snapshot

指定者：

接口 Cache 中的 getStats

覆盖：

类 BaseCache 中的 getStats

返回：

a Map of stats See also: Constant.java for the keys