EDU.oswego.cs.dl.util.concurrent

Class SyncMap

public class SyncMap extends Object implements Map

SyncMaps wrap Sync-based control around java.util.Maps. They operate in the same way as SyncCollection.

Reader operations are

size
isEmpty
get
containsKey
containsValue
keySet
entrySet
values

Writer operations are:

put
putAll
remove
clear

[ Introduction to this package. ]

See Also:

Field Summary
protected Map	c_
protected Sync	rd_
protected SynchronizedLong	syncFailures_
protected Sync	wr_

Constructor Summary
	SyncMap(Map map, Sync sync) Create a new SyncMap protecting the given map, and using the given sync to control both reader and writer methods.
	SyncMap(Map map, ReadWriteLock rwl) Create a new SyncMap protecting the given map, and using the given ReadWriteLock to control reader and writer methods.
	SyncMap(Map map, Sync readLock, Sync writeLock) Create a new SyncMap protecting the given map, and using the given pair of locks to control reader and writer methods.

Method Summary
protected void	afterRead(boolean wasInterrupted) Clean up after a reader operation *
protected boolean	beforeRead() Try to acquire sync before a reader operation; record failure *
void	clear()
boolean	containsKey(Object o)
boolean	containsValue(Object o)
Set	entrySet()
boolean	equals(Object o)
Object	get(Object key)
int	hashCode()
boolean	isEmpty()
Set	keySet()
Object	put(Object key, Object value)
void	putAll(Map coll)
Sync	readerSync() Return the Sync object managing read-only operations
Object	remove(Object key)
int	size()
long	syncFailures() Return the number of synchronization failures for read-only operations
Collection	values()
Sync	writerSync() Return the Sync object managing mutative operations

Field Detail

syncFailures_

protected final SynchronizedLong syncFailures_

Create a new SyncMap protecting the given map, and using the given sync to control both reader and writer methods. Common, reasonable choices for the sync argument include Mutex, ReentrantLock, and Semaphores initialized to 1.