Package com.tangosol.util

Class MultiBinaryLongMap.MaskedLongMapHolder

java.lang.Object

com.tangosol.util.MultiBinaryLongMap.MaskedLongMapHolder

Direct Known Subclasses:

MultiBinaryLongMap.LeftoverLongMapHolder

Enclosing class:

MultiBinaryLongMap

protected static class MultiBinaryLongMap.MaskedLongMapHolder
extends Object

MaskedLongMapHolder is used to produce MultiBinaryLongMap.MaskedBinaryLongMap instances backed by a shared BinaryLongMap. MaskedBinaryLongMap instances created by this holder are thread-safe and are all protected by the same shared and exclusive locks.

Field Summary

Fields

Modifier and Type	Field	Description
protected BinaryLongMap	f_blm	The BinaryLongMap shared by the component masked BLMs.
protected long	f_lMaskReserved	The bit-mask describing which bits in the underlying BLM representation are reserved (and may not be allocated by this holder).
protected Lock	f_lockS	The shared lock used to protected the logical contents of the maps exposed by this MaskedLongMapHolder.
protected Lock	f_lockX	The exclusive lock used to protected the logical contents of the maps exposed by this MaskedLongMapHolder.
protected List<MultiBinaryLongMap.MaskedBinaryLongMap>	m_listBLMs	The list of reserved masked BLMs, ordered by increasing shift-position.
protected long	m_lMaskFree	The bit-mask describing which bits in the underlying BLM representation are free.

Constructor Summary

Constructors

Constructor	Description
MaskedLongMapHolder(BinaryLongMap blm, Lock lockSMaster)	Construct a MaskedLongMapHolder backed by the specified blm.
MaskedLongMapHolder(BinaryLongMap blm, Lock lockSMaster, long lMaskReserved)	Construct a MaskedLongMapHolder backed by the specified blm with the specified reserved bit-mask.

Method Summary

Modifier and Type	Method	Description
protected void	checkRep()	Debugging function to check the representational invariant.
BinaryLongMap	getDelegateMap()	Return the BinaryLongMap that provides the underlying storage for this MaskedLongMapHolder.
protected MultiBinaryLongMap.MaskedBinaryLongMap	instantiateMaskedBinaryLongMap(int cShift, int cBits)	Factory method for instantiating MaskedBinaryLongMap instances associated with this MaskedLongMapHolder.
boolean	isEmpty()	Return true iff all non-reserved bits are free (not in-use).
boolean	releaseMap(MultiBinaryLongMap.MaskedBinaryLongMap blm)	Release a masked BLM that was reserved from this MaskedLongMapHolder.
BinaryLongMap	reserveMap(int cBits)	Reserve and return a masked BLM from this MaskedLongMapHolder if available, or null otherwise.
protected void	shiftMaskedMap(MultiBinaryLongMap.MaskedBinaryLongMap blm, int cShiftRight)	Shift the representation of the specified MaskedBinaryLongMap by the specified number of bits to the right.

Methods inherited from class java.lang.Object

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

Field Detail

m_listBLMs

protected List<MultiBinaryLongMap.MaskedBinaryLongMap> m_listBLMs

The list of reserved masked BLMs, ordered by increasing shift-position.

f_lMaskReserved

protected final long f_lMaskReserved

The bit-mask describing which bits in the underlying BLM representation are reserved (and may not be allocated by this holder).

m_lMaskFree

protected long m_lMaskFree

The bit-mask describing which bits in the underlying BLM representation are free.

f_lockS

protected final Lock f_lockS

The shared lock used to protected the logical contents of the maps exposed by this MaskedLongMapHolder.

f_lockX

protected final Lock f_lockX

The exclusive lock used to protected the logical contents of the maps exposed by this MaskedLongMapHolder.

f_blm

protected final BinaryLongMap f_blm

The BinaryLongMap shared by the component masked BLMs.

Constructor Detail

MaskedLongMapHolder

public MaskedLongMapHolder(BinaryLongMap blm,
                           Lock lockSMaster)

Construct a MaskedLongMapHolder backed by the specified blm.

Parameters:

blm - the BinaryLongMap that the component masked maps are backed by

lockSMaster - the shared master-lock for the MultiBinaryLongMap

MaskedLongMapHolder

public MaskedLongMapHolder(BinaryLongMap blm,
                           Lock lockSMaster,
                           long lMaskReserved)

Construct a MaskedLongMapHolder backed by the specified blm with the specified reserved bit-mask.

Parameters:

blm - the BinaryLongMap that the component masked maps are backed by

lockSMaster - the shared master-lock for the MultiBinaryLongMap

lMaskReserved - the bit-mask representing the reserved bits

Method Detail

getDelegateMap

public BinaryLongMap getDelegateMap()

Return the BinaryLongMap that provides the underlying storage for this MaskedLongMapHolder.

Returns:

the underlying BinaryLongMap

reserveMap

public BinaryLongMap reserveMap(int cBits)

Reserve and return a masked BLM from this MaskedLongMapHolder if available, or null otherwise. Reserved maps must be released when no longer needed.

Parameters:

cBits - the number of bits to use to store each value

Returns:

a masked BLM, or null

releaseMap

public boolean releaseMap(MultiBinaryLongMap.MaskedBinaryLongMap blm)

Release a masked BLM that was reserved from this MaskedLongMapHolder.

Parameters:

blm - the masked BLM to release

Returns:

true iff the MaskedLongMapHolder becomes empty as a result

isEmpty

public boolean isEmpty()

Return true iff all non-reserved bits are free (not in-use).

Returns:

true iff all non-reserved bits are free (not in use)

instantiateMaskedBinaryLongMap

protected MultiBinaryLongMap.MaskedBinaryLongMap instantiateMaskedBinaryLongMap(int cShift,
                                                                                int cBits)

Factory method for instantiating MaskedBinaryLongMap instances associated with this MaskedLongMapHolder.

Parameters:

cShift - the shift position of the masked BLM

cBits - the bit-width of values represented by the BLM

Returns:

a MaskedBinaryLongMap with the specified shift and mask associated with this LongMapHolder (and backed by the underlying BLM)

shiftMaskedMap

protected void shiftMaskedMap(MultiBinaryLongMap.MaskedBinaryLongMap blm,
                              int cShiftRight)

Shift the representation of the specified MaskedBinaryLongMap by the specified number of bits to the right.

Note: the caller must hold exclusive access to the underlying BLM (and by extension, exclusive access to all derived masked maps).

Parameters:

blm - the MaskedBinaryLongMap to shift

cShiftRight - the number of bits to shift to the right

checkRep

protected void checkRep()

Debugging function to check the representational invariant.