org.jboss.cache.lock
Class LockMap

java.lang.Object
  org.jboss.cache.lock.LockMap

public class LockMap
extends Object

Provide lock ownership mapping.

Version:

$Id: LockMap.java 7168 2008-11-19 17:37:20Z jason.greene@jboss.com $

Author:

Ben Wang

Field Summary

static int	OWNER_ANY
static int	OWNER_READ
static int	OWNER_WRITE

Constructor Summary

LockMap()

LockMap(Collection<Object> readOwners)
This constructor is made available for testing with different collection types for the readOwners collection.

Method Summary

void	addReader(Object owner) Adding a reader owner.
boolean	isOwner(Object caller, int ownership) Check whether this owner has reader or writer ownership.
boolean	isReadLocked()
String	printInfo() Debugging information.
Collection<Object>	readerOwners() Returns an unmodifiable set of reader owner objects.
void	releaseReaderOwners(LockStrategy lock)
void	removeAll() Remove all ownership.
void	removeReader(Object owner) Remove reader ownership.
void	removeWriter() Remove writer ownership.
void	setWriterIfNotNull(Object owner) Adding a writer owner.
boolean	upgrade(Object owner) Upgrading current reader ownership to writer one.
Object	writerOwner()

Methods inherited from class java.lang.Object

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

Field Detail

OWNER_ANY

public static final int OWNER_ANY

See Also:

Constant Field Values

OWNER_READ

public static final int OWNER_READ

See Also:

Constant Field Values

OWNER_WRITE

public static final int OWNER_WRITE

See Also:

Constant Field Values

Constructor Detail

LockMap

public LockMap()

LockMap

public LockMap(Collection<Object> readOwners)

This constructor is made available for testing with different collection types for the readOwners collection.

Parameters:

readOwners -

Method Detail

isOwner

public boolean isOwner(Object caller,
                       int ownership)

Check whether this owner has reader or writer ownership.

Parameters:

caller - the potential owner. Cannot be null.

ownership - Either OWNER_ANY, OWNER_READ, or OWNER_WRITE.

Returns:

true if the caller is the owner of the current lock

Throws:

NullPointerException - if caller is null.

addReader

public void addReader(Object owner)

Adding a reader owner.

Parameters:

owner -

setWriterIfNotNull

public void setWriterIfNotNull(Object owner)

Adding a writer owner.

Parameters:

owner -

upgrade

public boolean upgrade(Object owner)
                throws OwnerNotExistedException

Upgrading current reader ownership to writer one.

Parameters:

owner -

Returns:

True if successful.

Throws:

OwnerNotExistedException

readerOwners

public Collection<Object> readerOwners()

Returns an unmodifiable set of reader owner objects.

releaseReaderOwners

public void releaseReaderOwners(LockStrategy lock)

writerOwner

public Object writerOwner()

Returns:

Writer owner object. Null if none.

removeReader

public void removeReader(Object owner)

Remove reader ownership.

removeWriter

public void removeWriter()

Remove writer ownership.

removeAll

public void removeAll()

Remove all ownership.

printInfo

public String printInfo()

Debugging information.

Returns:

lock information

isReadLocked

public boolean isReadLocked()