CachedRider (egothor2 4.0.5-SNAPSHOT API)

java.lang.Object
- org.egothor.cache.CachedRider

All Implemented Interfaces:

Resolver<CachedTerm,CachedIListPage>
```
public class CachedRider
extends Object
implements Resolver<CachedTerm,CachedIListPage>
```
Represents a cache that stores pages of inverted lists for different barrels and terms.

Field Summary

Fields
Modifier and Type Field and Description

static int DEFAULT_PAGE_SIZE
Default maximum number of items an inverted list page should store.

Fields
Modifier and Type	Field and Description
`static int`	`DEFAULT_PAGE_SIZE` Default maximum number of items an inverted list page should store.

Constructor Summary

Constructors
Constructor and Description
`CachedRider(Cache<CachedTerm,CachedIListPage> cache)` Constructor for the CachedRider object.
`CachedRider(Cache<CachedTerm,CachedIListPage> cache, int pageSize)` Constructor for the CachedRider object.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`containsKey(CachedTerm term)` Checks whether the specified term is cached.
`CachedIListPage`	`get(CachedTerm term)` Gets the inverted list page associated with the specified term from the cache if the term is cached, or the inverted list page returned by the resolver.
`Cache<CachedTerm,CachedIListPage>`	`getCache()` Gets the actual cache used for storing inverted list pages.
`long`	`getCachedPostings()` Returns the actual number of cached postings.
`long`	`getPostings()` Returns the number of postings that the cached pages occupy.
`float`	`hitRatio()` Returns the hits/requests ratio in percents.
`long`	`hits()` Returns the number of all hits.
`long`	`misses()` Returns the number of all misses.
`IListReader`	`openIList(Barrel barrel, String term)` Gets a cached inverted list reader for the specified barrel and term.
`CachedIListPage`	`put(CachedTerm term, CachedIListPage page)` Adds a new inverted list page for the specified term to the cache.
`CachedIListPage`	`remove(CachedTerm term)` Removes the specified term and its page from the cache.
`long`	`requests()` Returns the number of all submitted requests.
`void`	`resetCounters()` Sets hits and misses counters to zero.
`CachedIListPage`	`resolve(CachedTerm term)` Return a new cached inverted list page of the specified term.
`int`	`size()` Returns the number of cached inverted list pages.
`CachedIListPage`	`update(CachedTerm term, CachedIListPage page)` Updates the inverted list page associated with the specified term in the cache if a cached page exists for the term.

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

- Field Detail
  - DEFAULT_PAGE_SIZE
```
public static int DEFAULT_PAGE_SIZE
```
    Default maximum number of items an inverted list page should store.
- Constructor Detail
  - CachedRider
```
public CachedRider(Cache<CachedTerm,CachedIListPage> cache)
```
    Constructor for the CachedRider object. Uses default inverted list page size.
    
    Parameters:
    
    cache - actual cache used for storing inverted list pages
  - CachedRider
```
public CachedRider(Cache<CachedTerm,CachedIListPage> cache,
                   int pageSize)
```
    Constructor for the CachedRider object.
    
    Parameters:
    
    cache - actual cache used for storing inverted list pages
    
    pageSize - maximum size of an inverted list page
- Method Detail
  - resolve
```
public CachedIListPage resolve(CachedTerm term)
```
    Return a new cached inverted list page of the specified term.
    
    Specified by:
    
    resolve in interface Resolver<CachedTerm,CachedIListPage>
    
    Parameters:
    
    term - term to create the inverted list page for
    
    Returns:
    
    new cached inverted list page for the specified term
  - put
```
public CachedIListPage put(CachedTerm term,
                           CachedIListPage page)
```
    Adds a new inverted list page for the specified term to the cache. If the term was previously cached, it is removed at first. If the cache is full, a page is removed from the cache according to the current eviction policy.
    
    Parameters:
    
    term - term to add to the cache
    
    page - inverted list page to map the term to
    
    Returns:
    
    previous inverted list page associated with the term or null if a previous mapping did not exists in the cache for the specified term
  - get
```
public CachedIListPage get(CachedTerm term)
```
    Gets the inverted list page associated with the specified term from the cache if the term is cached, or the inverted list page returned by the resolver.
    
    Parameters:
    
    term - term to get the result for
    
    Returns:
    
    inverted list page associated with the term from the cache, or from the resolver if the term was not cached
  - remove
```
public CachedIListPage remove(CachedTerm term)
```
    Removes the specified term and its page from the cache.
    
    Parameters:
    
    term - term to remove from the cache.
    
    Returns:
    
    inverted list page associated with the term, or null if the term was not cached
  - update
```
public CachedIListPage update(CachedTerm term,
                              CachedIListPage page)
```
    Updates the inverted list page associated with the specified term in the cache if a cached page exists for the term.
    
    Parameters:
    
    term - term to change the result for
    
    page - new inverted list page associated with the key
    
    Returns:
    
    previous associated page or null if the term is not cached
  - containsKey
```
public boolean containsKey(CachedTerm term)
```
    Checks whether the specified term is cached.
    
    Parameters:
    
    term - term to check
    
    Returns:
    
    true, if the term is currently cached, false otherwise
  - openIList
```
public IListReader openIList(Barrel barrel,
                             String term)
```
    Gets a cached inverted list reader for the specified barrel and term.
    
    Parameters:
    
    barrel - barrel to get the inverted list from
    
    term - term owning the requested inverted list
    
    Returns:
    
    cached inverted list reader
  - getCache
```
public Cache<CachedTerm,CachedIListPage> getCache()
```
    Gets the actual cache used for storing inverted list pages.
    
    Returns:
    
    actual cache used for storing inverted list pages
  - hits
```
public long hits()
```
    Returns the number of all hits.
    
    Returns:
    
    number of all hits
  - misses
```
public long misses()
```
    Returns the number of all misses.
    
    Returns:
    
    number of all misses
  - hitRatio
```
public float hitRatio()
```
    Returns the hits/requests ratio in percents.
    
    Returns:
    
    hit ratio of the cache
  - requests
```
public long requests()
```
    Returns the number of all submitted requests.
    
    Returns:
    
    number of all submitted requests
  - resetCounters
```
public void resetCounters()
```
    Sets hits and misses counters to zero.
  - size
```
public int size()
```
    Returns the number of cached inverted list pages.
    
    Returns:
    
    number cached inverted list pages
  - getPostings
```
public long getPostings()
```
    Returns the number of postings that the cached pages occupy.
    
    Returns:
    
    number of postings that the cached pages occupy
  - getCachedPostings
```
public long getCachedPostings()
```
    Returns the actual number of cached postings.
    
    Returns:
    
    actual number of cached postings

Class CachedRider

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_PAGE_SIZE

Constructor Detail

CachedRider

CachedRider

Method Detail

resolve

put

get

remove

update

containsKey

openIList

getCache

hits

misses

hitRatio

requests

resetCounters

size

getPostings

getCachedPostings