CachingDictionary.ItemCache (JWI 2.4.0 API)

java.lang.Object
- edu.mit.jwi.CachingDictionary.ItemCache

All Implemented Interfaces:

IClosable, IHasLifecycle, ICachingDictionary.IItemCache

Enclosing class:

CachingDictionary
```
public static class CachingDictionary.ItemCache
extends Object
implements ICachingDictionary.IItemCache
```
An LRU cache for objects in JWI.

Since:

JWI 2.2.0

Version:

2.4.0

Author:

Mark A. Finlayson

Nested Class Summary
- Nested classes/interfaces inherited from interface edu.mit.jwi.data.IHasLifecycle
  IHasLifecycle.LifecycleState, IHasLifecycle.ObjectClosedException, IHasLifecycle.ObjectOpenException

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`DEFAULT_INITIAL_CAPACITY`
`static float`	`DEFAULT_LOAD_FACTOR`
`static int`	`DEFAULT_MAXIMUM_CAPACITY`
`protected Map<IItemID<?>,IItem<?>>`	`itemCache`
`protected Map<ISenseKey,IWord>`	`keyCache`
`protected Lock`	`lifecycleLock`
`protected Map<ISenseKey,ISenseEntry>`	`senseCache`

Constructor Summary

Constructors
Constructor and Description
`ItemCache()` Default constructor that initializes the dictionary with caching enabled.
`ItemCache(int initialCapacity, int maxCapacity, boolean enabled)` Caller can specify both the initial size, maximum size, and the initial state of caching.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`cacheItem(IItem<?> item)` Caches the specified item, if this cache is enabled.
`void`	`cacheSenseEntry(ISenseEntry entry)` Caches the specified entry.
`void`	`cacheWordByKey(IWord word)` Caches the specified word, indexed by its sense key.
`protected void`	`checkOpen()` An internal method for assuring compliance with the dictionary interface that says that methods will throw `ObjectClosedException`s if the dictionary has not yet been opened.
`void`	`clear()` Removes all entries from the cache.
`void`	`close()` This closes the object by disposing of data backing objects or connections.
`int`	`getInitialCapacity()` Returns the initial capacity of this cache.
`int`	`getMaximumCapacity()` Returns the maximum capacity of this cache.
`boolean`	`isEnabled()` Returns `true` if this cache is enabled; `false` otherwise.
`boolean`	`isOpen()` Returns `true` if the dictionary is open, that is, ready to accept queries; returns `false` otherwise
`protected <K,V> Map<K,V>`	`makeCache(int initialCapacity)` Creates the map that backs this cache.
`boolean`	`open()` This opens the object by performing any required initialization steps.
`protected void`	`reduceCacheSize(Map<?,?> cache)` Brings the map size into line with the specified maximum capacity of this cache.
`<T extends IItem<D>,D extends IItemID<T>> T`	`retrieveItem(D id)` Retrieves the item identified by the specified id.
`ISenseEntry`	`retrieveSenseEntry(ISenseKey key)` Retrieves the sense entry identified by the specified sense key.
`IWord`	`retrieveWord(ISenseKey key)` Retrieves the word identified by the specified sense key.
`void`	`setEnabled(boolean isEnabled)` Enables (`true`) or disables (`false`) caching.
`void`	`setInitialCapacity(int capacity)` Sets the initial capacity of the cache
`void`	`setMaximumCapacity(int capacity)` Sets the maximum capacity of the cache
`int`	`size()` Returns the number of items in the cache.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - DEFAULT_INITIAL_CAPACITY
```
public static final int DEFAULT_INITIAL_CAPACITY
```
    See Also:
    
    Constant Field Values
  - DEFAULT_MAXIMUM_CAPACITY
```
public static final int DEFAULT_MAXIMUM_CAPACITY
```
    See Also:
    
    Constant Field Values
  - DEFAULT_LOAD_FACTOR
```
public static final float DEFAULT_LOAD_FACTOR
```
    See Also:
    
    Constant Field Values
  - lifecycleLock
```
protected Lock lifecycleLock
```
  - itemCache
```
protected Map<IItemID<?>,IItem<?>> itemCache
```
  - keyCache
```
protected Map<ISenseKey,IWord> keyCache
```
  - senseCache
```
protected Map<ISenseKey,ISenseEntry> senseCache
```
- Constructor Detail
  - ItemCache
```
public ItemCache()
```
    Default constructor that initializes the dictionary with caching enabled.
    
    Since:
    
    JWI 2.2.0
  - ItemCache
```
public ItemCache(int initialCapacity,
                 int maxCapacity,
                 boolean enabled)
```
    Caller can specify both the initial size, maximum size, and the initial state of caching.
    
    Parameters:
    
    initialCapacity - the initial capacity of the cache
    
    maxCapacity - the maximum capacity of the cache
    
    enabled - whether the cache starts out enabled
    
    Since:
    
    JWI 2.2.0
- Method Detail
  - open
```
public boolean open()
             throws IOException
```
    Description copied from interface: IHasLifecycle
    
    This opens the object by performing any required initialization steps. If this method returns false, then subsequent calls to IHasLifecycle.isOpen() will return false.
    
    Specified by:
    
    open in interface IHasLifecycle
    
    Returns:
    
    true if there were no errors in initialization; false otherwise.
    
    Throws:
    
    IOException - if there was IO error while performing initializataion
  - makeCache
```
protected <K,V> Map<K,V> makeCache(int initialCapacity)
```
    Creates the map that backs this cache.
    
    Type Parameters:
    
    K - the key type
    
    V - the value type
    
    Parameters:
    
    initialCapacity - the initial capacity
    
    Returns:
    
    the new map
    
    Since:
    
    JWI 2.2.0
  - isOpen
```
public boolean isOpen()
```
    Description copied from interface: IHasLifecycle
    
    Returns true if the dictionary is open, that is, ready to accept queries; returns false otherwise
    
    Specified by:
    
    isOpen in interface IHasLifecycle
    
    Returns:
    
    true if the object is open; false otherwise
  - checkOpen
```
protected void checkOpen()
```
    An internal method for assuring compliance with the dictionary interface that says that methods will throw ObjectClosedExceptions if the dictionary has not yet been opened.
    
    Throws:
    
    ObjectClosedException - if the dictionary is closed.
    
    Since:
    
    JWI 2.2.0
  - close
```
public void close()
```
    Description copied from interface: IClosable
    
    This closes the object by disposing of data backing objects or connections. If the object is already closed, or in the process of closing, this method does nothing (although, if the object is in the process of closing, it may block until closing is complete).
    
    Specified by:
    
    close in interface IClosable
  - clear
```
public void clear()
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Removes all entries from the cache.
    
    Specified by:
    
    clear in interface ICachingDictionary.IItemCache
  - isEnabled
```
public boolean isEnabled()
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Returns true if this cache is enabled; false otherwise. If a cache is enabled, it will cache an item passed to its cache methods.
    
    Specified by:
    
    isEnabled in interface ICachingDictionary.IItemCache
    
    Returns:
    
    true if this cache is enabled; false otherwise
  - setEnabled
```
public void setEnabled(boolean isEnabled)
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Enables (true) or disables (false) caching.
    
    Specified by:
    
    setEnabled in interface ICachingDictionary.IItemCache
    
    Parameters:
    
    isEnabled - if true, caching is enabled; if false, caching is disabled.
  - getInitialCapacity
```
public int getInitialCapacity()
```
    Returns the initial capacity of this cache.
    
    Returns:
    
    the initial capacity of this cache.
    
    Since:
    
    JWI 2.2.0
  - setInitialCapacity
```
public void setInitialCapacity(int capacity)
```
    Sets the initial capacity of the cache
    
    Parameters:
    
    capacity - the initial capacity
    
    Since:
    
    JWI 2.2.0
  - getMaximumCapacity
```
public int getMaximumCapacity()
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Returns the maximum capacity of this cache.
    
    Specified by:
    
    getMaximumCapacity in interface ICachingDictionary.IItemCache
    
    Returns:
    
    the maximum capacity of this cache.
  - setMaximumCapacity
```
public void setMaximumCapacity(int capacity)
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Sets the maximum capacity of the cache
    
    Specified by:
    
    setMaximumCapacity in interface ICachingDictionary.IItemCache
    
    Parameters:
    
    capacity - the maximum capacity
  - size
```
public int size()
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Returns the number of items in the cache.
    
    Specified by:
    
    size in interface ICachingDictionary.IItemCache
    
    Returns:
    
    the number of items in the cache.
  - cacheItem
```
public void cacheItem(IItem<?> item)
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Caches the specified item, if this cache is enabled. Otherwise does nothing.
    
    Specified by:
    
    cacheItem in interface ICachingDictionary.IItemCache
    
    Parameters:
    
    item - the item to be cached; may not be null
  - cacheWordByKey
```
public void cacheWordByKey(IWord word)
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Caches the specified word, indexed by its sense key.
    
    Specified by:
    
    cacheWordByKey in interface ICachingDictionary.IItemCache
    
    Parameters:
    
    word - the word to be cached; may not be null
  - cacheSenseEntry
```
public void cacheSenseEntry(ISenseEntry entry)
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Caches the specified entry.
    
    Specified by:
    
    cacheSenseEntry in interface ICachingDictionary.IItemCache
    
    Parameters:
    
    entry - the entry to be cached; may not be null
  - reduceCacheSize
```
protected void reduceCacheSize(Map<?,?> cache)
```
    Brings the map size into line with the specified maximum capacity of this cache.
    
    Parameters:
    
    cache - the map to be trimmed
    
    Since:
    
    JWI 2.2.0
  - retrieveItem
```
public <T extends IItem<D>,D extends IItemID<T>> T retrieveItem(D id)
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Retrieves the item identified by the specified id.
    
    Specified by:
    
    retrieveItem in interface ICachingDictionary.IItemCache
    
    Type Parameters:
    
    T - the type of the item
    
    D - the type of the item id
    
    Parameters:
    
    id - the id for the requested item
    
    Returns:
    
    the item for the specified id, or null if not present in the cache
  - retrieveWord
```
public IWord retrieveWord(ISenseKey key)
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Retrieves the word identified by the specified sense key.
    
    Specified by:
    
    retrieveWord in interface ICachingDictionary.IItemCache
    
    Parameters:
    
    key - the sense key for the requested word
    
    Returns:
    
    the word for the specified key, or null if not present in the cache
  - retrieveSenseEntry
```
public ISenseEntry retrieveSenseEntry(ISenseKey key)
```
    Description copied from interface: ICachingDictionary.IItemCache
    
    Retrieves the sense entry identified by the specified sense key.
    
    Specified by:
    
    retrieveSenseEntry in interface ICachingDictionary.IItemCache
    
    Parameters:
    
    key - the sense key for the requested sense entry
    
    Returns:
    
    the sense entry for the specified key, or null if not present in the cache

Class CachingDictionary.ItemCache

Nested Class Summary

Nested classes/interfaces inherited from interface edu.mit.jwi.data.IHasLifecycle

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_INITIAL_CAPACITY

DEFAULT_MAXIMUM_CAPACITY

DEFAULT_LOAD_FACTOR

lifecycleLock

itemCache

keyCache

senseCache

Constructor Detail

ItemCache

ItemCache

Method Detail

open

makeCache

isOpen

checkOpen

close

clear

isEnabled

setEnabled

getInitialCapacity

setInitialCapacity

getMaximumCapacity

setMaximumCapacity

size

cacheItem

cacheWordByKey

cacheSenseEntry

reduceCacheSize

retrieveItem

retrieveWord

retrieveSenseEntry