org.objectweb.cjdbc.controller.cache.result.entries
Class ResultCacheEntry

java.lang.Object
  org.objectweb.cjdbc.controller.cache.result.entries.ResultCacheEntry

All Implemented Interfaces:

CacheEntry

Direct Known Subclasses:

ResultCacheEntryEager, ResultCacheEntryNoCache, ResultCacheEntryRelaxed

public abstract class ResultCacheEntry

extends java.lang.Object

implements CacheEntry

A CacheEntry represents a SQL select request with its reponse. The cache entry can have 3 states:

• CACHE_VALID when it is valid
• CACHE_DIRTY when the result has been marked dirty (may be invalid)
• CACHE_INVALID when there is no result (request has to be re-issued to the database)

Version:

1.0

Author:

Emmanuel Cecchet

Field Summary

private CacheEntry	next
private CacheEntry	prev
protected SelectRequest	request
protected ControllerResultSet	result
protected int	state

Fields inherited from interface org.objectweb.cjdbc.controller.cache.result.entries.CacheEntry

CACHE_DIRTY, CACHE_INVALID, CACHE_VALID, NO_DEADLINE

Constructor Summary

ResultCacheEntry(SelectRequest request, ControllerResultSet result)
Creates a new CacheEntry instance.

Method Summary

CacheEntry	getNext() Gets the value of next ResultCacheEntry in LRU.
CacheEntry	getPrev() Gets the value of previous ResultCacheEntry in LRU.
SelectRequest	getRequest() Returns the SELECT request of this cache entry.
ControllerResultSet	getResult() Returns the ControllerResultSet of the cached select request
int	getSizeOfResult() Size of the result in bytes
java.lang.String	getState() Get the state of this entry as a string
abstract java.lang.String	getType() Get the type of this entry as a string
abstract void	invalidate() Invalidates this cache entry (removes the ResultSet and turn state to CacheEntry.CACHE_INVALID).
boolean	isDirty() Returns true if cache entry state is marked dirty (state is CacheEntry.CACHE_DIRTY).
boolean	isValid() Return true if cache entry state is valid (state is CacheEntry.CACHE_VALID).
void	markDirty() Marks this entry dirty (state becomes CacheEntry.CACHE_DIRTY).
void	setNext(CacheEntry next) Sets the value of next ResultCacheEntry in LRU.
void	setPrev(CacheEntry prev) Sets the value of previous ResultCacheEntry in LRU.
void	setResult(ControllerResultSet result) Set a new ControllerResultSet of the cached select request (cache update).
void	setValid() Marks this entry valid (state becomes CacheEntry.CACHE_VALID).
abstract java.lang.String[]	toStringTable() Get data about this entry

Methods inherited from class java.lang.Object

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

Field Detail

request

protected SelectRequest request

result

protected ControllerResultSet result

state

protected int state

next

private CacheEntry next

prev

private CacheEntry prev

Constructor Detail

ResultCacheEntry

public ResultCacheEntry(SelectRequest request,
                        ControllerResultSet result)

Creates a new CacheEntry instance.

Parameters:

request - a SelectRequest value

result - a ControllerResultSet value

Method Detail

getType

public abstract java.lang.String getType()

Get the type of this entry as a string

Specified by:

getType in interface CacheEntry

Returns:

NoCache or Eager or Relaxed

getState

public java.lang.String getState()

Get the state of this entry as a string

Specified by:

getState in interface CacheEntry

Returns:

Valid or Dirty or Invalid

isValid

public boolean isValid()

Return true if cache entry state is valid (state is CacheEntry.CACHE_VALID).

Specified by:

isValid in interface CacheEntry

Returns:

a boolean value

isDirty

public boolean isDirty()

Returns true if cache entry state is marked dirty (state is CacheEntry.CACHE_DIRTY).

Specified by:

isDirty in interface CacheEntry

Returns:

a boolean value

getRequest

public SelectRequest getRequest()

Returns the SELECT request of this cache entry.

Specified by:

getRequest in interface CacheEntry

Returns:

a SelectRequest value

getResult

public ControllerResultSet getResult()

Returns the ControllerResultSet of the cached select request

Specified by:

getResult in interface CacheEntry

Returns:

a ControllerResultSet value

setResult

public void setResult(ControllerResultSet result)

Set a new ControllerResultSet of the cached select request (cache update).

The cache state is automatically set to valid (CacheEntry.CACHE_VALID).

Specified by:

setResult in interface CacheEntry

Parameters:

result - a ControllerResultSet value

invalidate

public abstract void invalidate()

Invalidates this cache entry (removes the ResultSet and turn state to CacheEntry.CACHE_INVALID).

Specified by:

invalidate in interface CacheEntry

markDirty

public void markDirty()

Marks this entry dirty (state becomes CacheEntry.CACHE_DIRTY).

The ResultSet if not affected by this method.

Specified by:

markDirty in interface CacheEntry

setValid

public void setValid()

Marks this entry valid (state becomes CacheEntry.CACHE_VALID).

Specified by:

setValid in interface CacheEntry

getNext

public CacheEntry getNext()

Gets the value of next ResultCacheEntry in LRU.

Specified by:

getNext in interface CacheEntry

Returns:

value of next.

setNext

public void setNext(CacheEntry next)

Sets the value of next ResultCacheEntry in LRU.

Specified by:

setNext in interface CacheEntry

Parameters:

next - value to assign to next.

getPrev

public CacheEntry getPrev()

Gets the value of previous ResultCacheEntry in LRU.

Specified by:

getPrev in interface CacheEntry

Returns:

value of previous.

setPrev

public void setPrev(CacheEntry prev)

Sets the value of previous ResultCacheEntry in LRU.

Specified by:

setPrev in interface CacheEntry

Parameters:

prev - value to assign to prev.

toStringTable

public abstract java.lang.String[] toStringTable()

Get data about this entry

Specified by:

toStringTable in interface CacheEntry

Returns:

an array [request,type,status(valid,notvalid,dirty),deadLine]

getSizeOfResult

public int getSizeOfResult()

Size of the result in bytes

Specified by:

getSizeOfResult in interface CacheEntry

Returns:

an integer