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

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

Direct Known Subclasses:

ResultCacheEntryEager, ResultCacheEntryNoCache, ResultCacheEntryRelaxed

public abstract class AbstractResultCacheEntry

extends java.lang.Object

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

static int	CACHE_DIRTY This entry is dirty
static int	CACHE_INVALID This entry is no more valid and is not consistent with real data.
static int	CACHE_VALID State this entry is valid
private AbstractResultCacheEntry	next
static int	NO_DEADLINE This entry has no deadline
private AbstractResultCacheEntry	prev
protected SelectRequest	request
protected ControllerResultSet	result
protected int	state

Constructor Summary

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

Method Summary

AbstractResultCacheEntry	getNext() Gets the value of next AbstractResultCacheEntry in LRU.
AbstractResultCacheEntry	getPrev() Gets the value of previous AbstractResultCacheEntry 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 CACHE_INVALID).
boolean	isDirty() Returns true if cache entry state is marked dirty (state is CACHE_DIRTY).
boolean	isValid() Return true if cache entry state is valid (state is CACHE_VALID).
void	markDirty() Marks this entry dirty (state becomes CACHE_DIRTY).
void	setNext(AbstractResultCacheEntry next) Sets the value of next AbstractResultCacheEntry in LRU.
void	setPrev(AbstractResultCacheEntry prev) Sets the value of previous AbstractResultCacheEntry 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 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 AbstractResultCacheEntry next

prev

private AbstractResultCacheEntry prev

NO_DEADLINE

public static final int NO_DEADLINE

This entry has no deadline

See Also:

Constant Field Values

CACHE_VALID

public static final int CACHE_VALID

State this entry is valid

See Also:

Constant Field Values

CACHE_DIRTY

public static final int CACHE_DIRTY

This entry is dirty

See Also:

Constant Field Values

CACHE_INVALID

public static final int CACHE_INVALID

This entry is no more valid and is not consistent with real data.

See Also:

Constant Field Values

Constructor Detail

AbstractResultCacheEntry

public AbstractResultCacheEntry(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

Returns:

NoCache or Eager or Relaxed

getState

public java.lang.String getState()

Get the state of this entry as a string

Returns:

Valid or Dirty or Invalid

isValid

public boolean isValid()

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

Returns:

a boolean value

isDirty

public boolean isDirty()

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

Returns:

a boolean value

getRequest

public SelectRequest getRequest()

Returns the SELECT request of this cache entry.

Returns:

a SelectRequest value

getResult

public ControllerResultSet getResult()

Returns the ControllerResultSet of the cached select request

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 (CACHE_VALID).

Parameters:

result - a ControllerResultSet value

invalidate

public abstract void invalidate()

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

markDirty

public void markDirty()

Marks this entry dirty (state becomes CACHE_DIRTY).

The ResultSet if not affected by this method.

setValid

public void setValid()

Marks this entry valid (state becomes CACHE_VALID).

getNext

public AbstractResultCacheEntry getNext()

Gets the value of next AbstractResultCacheEntry in LRU.

Returns:

value of next.

setNext

public void setNext(AbstractResultCacheEntry next)

Sets the value of next AbstractResultCacheEntry in LRU.

Parameters:

next - value to assign to next.

getPrev

public AbstractResultCacheEntry getPrev()

Gets the value of previous AbstractResultCacheEntry in LRU.

Returns:

value of previous.

setPrev

public void setPrev(AbstractResultCacheEntry prev)

Sets the value of previous AbstractResultCacheEntry in LRU.

Parameters:

prev - value to assign to prev.

toStringTable

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

Get data about this entry

Returns:

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

getSizeOfResult

public int getSizeOfResult()

Size of the result in bytes

Returns:

an integer