Overview | Package | Class | Tree | Index | Help

Oracle® Coherence Java API Reference
v3.5.3
E15583-01
PREV CLASS NEXT CLASS | FRAMES NO FRAMES
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD

## com.tangosol.net.cache
Class SimpleOverflowMap.Status

    java.lang.Object
      com.tangosol.net.cache.SimpleOverflowMap.Status

Enclosing class:
  SimpleOverflowMap

    protected static class SimpleOverflowMap.Status

extends java.lang.Object

The Status object is used to manage concurrency at the key level for the key-level operations against the Map, to track all the items in the front Map, to manage the state transition for operations occurring against the Map, and to coordinate events across multiple threads.

Field Summary
`protected static int` | `STATE_MASK_FRONT` Bitmask for entry in front.
`protected static int` | `STATE_MASK_INSYNC` Bitmask for value in front and back being in sync.
`protected static int` | `STATE_MASK_RETAIN` Bitmask for fields that would indicate that the Status must not be discarded.
`protected static int` | `STATE_MASK_STATUS` Bitmask for status (least significant three bits reserved).
`protected static int` | `STATE_VALUE_RETAIN` Bit values for fields that would indicate that the Status can be discarded.
`protected static int` | `STATUS_AVAILABLE` Status: The Status object exists and no thread is currently performing processing against the associated entry.
`protected static int` | `STATUS_COMMITTING` Status: The Status object represents an Entry that was very recently being processed, and is currently finalizing the results of that processing.
`protected static int` | `STATUS_INVALIDATED` Status: The Status object has been discarded.
`protected static int` | `STATUS_PROCESSING` Status: The Status object represents an Entry that is currently being processed.
`protected static int` | `STATUS_RESERVED` Status: The Status object has been reserved for processing by a thread but is not yet processing.

Constructor Summary
`SimpleOverflowMap.Status()` Construct a Status object for a specific key.

Method Summary
`MapEvent` | `closeProcessing()` Finish the processing of the entry for which this Status exists and proceed to the commit phase.
`protected boolean` | `commitAndMaybeInvalidate()` Finish the commit for the entry for which this Status exists.
`protected boolean` | `extractFlag(int nMask)` Extract a particular masked flag from the state of the Status object.
`protected int` | `extractState(int nMask)` Extract a particular masked value from the state of the Status object.
`java.lang.String` | `getDescription()` Assemble a human-readable description.
`protected MapEvent` | `getFrontEvent()` For internal use only, return the current event from the front Map.
`java.lang.Thread` | `getOwnerThread()` Determine the thread that owns the Status object, if the Status object is processing or committing.
`protected int` | `getState()` Determine the state of the Status object.
`protected int` | `getStatus()` Determine the enumerated status of the Status object.
`boolean` | `hasEvent()` Determine if an event has occurred against the Entry for which this Status exists.
`boolean` | `isAvailable()` Determine if the Status object is available.
`boolean` | `isBackUpToDate()` Determine if the entry for which this Status exists has the same value in the front Map as in the back Map.
`boolean` | `isCommitting()` Determine if the Status object represents an Entry that has been processed and the results of that processing are being committed.
`protected boolean` | `isDiscardable()` Determine if this Status object can be discarded.
`boolean` | `isEntryInFront()` Determine if the entry for which this Status exists is present in the front map.
`boolean` | `isOwnedByCurrentThread()` Determine if the current thread owns this Status object.
`boolean` | `isProcessing()` Determine if the Status object represents an Entry that is currently being processed.
`boolean` | `isReserved()` Determine if the Status object is reserved.
`boolean` | `isValid()` Determine if the Status object is valid.
`protected MapEvent` | `mergeEvents(MapEvent evtOld, MapEvent evtNew)` Merge two events that have been raised in sequence from a given map.
`boolean` | `registerFrontEvent(MapEvent evt)` Register a MapEvent that has been raised by the front Map against the same key for which this Status object exists.
`protected boolean` | `requestReservation()` Attempt to reserve the Status by marking it as committing if it is available.
`void` | `setBackUpToDate(boolean fUpToDate)` Specify that the value stored in the back Map is known to be up to date (not needing to be written to the back if evicted from the front).
`void` | `setEntryInFront(boolean fEntryInFront)` Specify whether the entry for which this Status exists is present in the front map.
`protected void` | `setFrontEvent(MapEvent evt)` For internal use only, store the current event from the front Map.
`protected void` | `setOwnerThread(java.lang.Thread thread)` Specify the thread that owns the Status object.
`protected void` | `setState(int nState)` Specify the state of the Status object.
`protected void` | `setStatus(int nStatus)` Determine the enumerated state of the Status object.
`MapEvent` | `takeEvent()` Obtain the most recent front Map event that has occurred against the Entry for which this Status exists.
`java.lang.String` | `toString()` Returns a string representation of the object.
`protected void` | `updateFlag(int nMask, boolean f)` Update a particular masked flag within the state of the Status object.
`protected void` | `updateState(int nMask, int nValue)` Update a particular masked value within the state of the Status object.
`protected MapEvent` | `useReservation()` After having successfully made a reservation, this method completes the reservation process by setting the status to processing for the thread that made the reservation.
`protected MapEvent` | `waitForAvailable()` Wait for the Entry that this Status represents to become available.
`protected void` | `waitForReservationDecision()` Wait for the Entry that this Status represents to no longer be reserved.

Field Detail

### STATE_MASK_STATUS

    protected static final int STATE_MASK_STATUS

  Bitmask for status (least significant three bits reserved).

  See Also:
    Constant Field Values

### STATE_MASK_FRONT

    protected static final int STATE_MASK_FRONT

  Bitmask for entry in front.

  See Also:
    Constant Field Values

### STATE_MASK_INSYNC

    protected static final int STATE_MASK_INSYNC

  Bitmask for value in front and back being in sync.

  See Also:
    Constant Field Values

### STATUS_AVAILABLE

    protected static final int STATUS_AVAILABLE

  Status: The Status object exists and no thread is currently performing processing against the associated entry.

  See Also:
    Constant Field Values

### STATUS_RESERVED

    protected static final int STATUS_RESERVED

  Status: The Status object has been reserved for processing by a thread but is not yet processing.

  See Also:
    Constant Field Values

### STATUS_PROCESSING

    protected static final int STATUS_PROCESSING

  Status: The Status object represents an Entry that is currently being processed.

  See Also:
    Constant Field Values

### STATUS_COMMITTING

    protected static final int STATUS_COMMITTING

  Status: The Status object represents an Entry that was very recently being processed, and is currently finalizing the results of that processing.

  See Also:
    Constant Field Values

### STATUS_INVALIDATED

    protected static final int STATUS_INVALIDATED

  Status: The Status object has been discarded.

  See Also:
    Constant Field Values

### STATE_MASK_RETAIN

    protected static final int STATE_MASK_RETAIN

  Bitmask for fields that would indicate that the Status must not be discarded.

  See Also:
    Constant Field Values

### STATE_VALUE_RETAIN

    protected static final int STATE_VALUE_RETAIN

  Bit values for fields that would indicate that the Status can be discarded.

  See Also:
    Constant Field Values

Constructor Detail

### SimpleOverflowMap.Status

    public SimpleOverflowMap.Status()

  Construct a Status object for a specific key.

Method Detail

### getStatus

    protected int getStatus()

  Determine the enumerated status of the Status object. This value is intended for internal and debugging use only, and should have no meaning to any external consumer.

  Returns:
    a number corresponding to the enumeration of states as represented by the STATUS_*

### setStatus

    protected void setStatus(int nStatus)

  Determine the enumerated state of the Status object. This value is intended for internal and debugging use only, and should have no meaning to any external consumer.

  Parameters:
    `nStatus` - a number corresponding to one of the enumeration represented by the STATUS_* constants

### isValid

    public boolean isValid()

  Determine if the Status object is valid. A Status object can be discarded (no longer used), in which case it will not be valid.

  Returns:
    true iff the Status object is still valid

### isAvailable

    public boolean isAvailable()

  Determine if the Status object is available. A Status object is available if it is valid and no thread is currently processing the entry for which this Status object exists.

  Returns:
    true iff the Status object is available

### isReserved

    public boolean isReserved()

  Determine if the Status object is reserved.

  Returns:
    true iff the Status object is available

### isProcessing

    public boolean isProcessing()

  Determine if the Status object represents an Entry that is currently being processed.

  Returns:
    true iff the entry represented by this Status object is being processed

### isCommitting

    public boolean isCommitting()

  Determine if the Status object represents an Entry that has been processed and the results of that processing are being committed. The "committing" status implies that no other thread is allowed to do anything related to the entry that this Status represents.

  Returns:
    true iff the entry represented by this Status object is being committed

### getOwnerThread

    public java.lang.Thread getOwnerThread()

  Determine the thread that owns the Status object, if the Status object is processing or committing.

  Returns:
    the owning thread, or null

### setOwnerThread

    protected void setOwnerThread(java.lang.Thread thread)

  Specify the thread that owns the Status object. For internal use only.

  Parameters:
    `thread` - the owning thread, or null

### isOwnedByCurrentThread

    public boolean isOwnedByCurrentThread()

  Determine if the current thread owns this Status object.

  Returns:
    true iff the current thread owns this Status object

### isEntryInFront

    public boolean isEntryInFront()

  Determine if the entry for which this Status exists is present in the front map.

  Returns:
    true iff the entry is stored in the front map

### setEntryInFront

    public void setEntryInFront(boolean fEntryInFront)

  Specify whether the entry for which this Status exists is present in the front map.

  Parameters:
    `fEntryInFront` - pass true if the entry is stored in the front map, false if not

### isBackUpToDate

    public boolean isBackUpToDate()

  Determine if the entry for which this Status exists has the same value in the front Map as in the back Map.

  Returns:
    true iff the value exists in the back Map, and the value in the front Map is the same as the value in the back Map

### setBackUpToDate

    public void setBackUpToDate(boolean fUpToDate)

  Specify that the value stored in the back Map is known to be up to date (not needing to be written to the back if evicted from the front).

### getFrontEvent

    protected MapEvent getFrontEvent()

  For internal use only, return the current event from the front Map. All handling of synchronization etc. is the responsibility of the sub-class.

  Returns:
    the cummulative front Map event for the Entry represented by this Status object, or null if there were no events

### setFrontEvent

    protected void setFrontEvent(MapEvent evt)

  For internal use only, store the current event from the front Map. All handling of synchronization etc. is the responsibility of the sub-class.

  Parameters:
    `evt` - the cummulative front Map event for the Entry represented by this Status object, or null to clear the event

### hasEvent

    public boolean hasEvent()

  Determine if an event has occurred against the Entry for which this Status exists.

  Returns:
    true iff an event is held by the Status

### takeEvent

    public MapEvent takeEvent()

  Obtain the most recent front Map event that has occurred against the Entry for which this Status exists.

  Returns:
    the cummulative front Map event for the Entry represented by this Status object, or null if there were no events

### isDiscardable

    protected boolean isDiscardable()

  Determine if this Status object can be discarded.

  This is an internal method.

  Returns:
    true iff this Status object can be discarded

### getDescription

    public java.lang.String getDescription()

  Assemble a human-readable description.

  Returns:
    a description of this Status object

### toString

    public java.lang.String toString()

  Returns a string representation of the object.

  Returns:
    a string representation of the object

### waitForAvailable

    protected MapEvent waitForAvailable()

  Wait for the Entry that this Status represents to become available. Once it becomes available, the current thread will automatically become the owner and the status will be changed to "processing".

  This is an internal method. It requires the caller to have synchronized on the Status object before calling this method.

  Returns:
    whatever event was deferred for this Status which the caller must handle

### requestReservation

    protected boolean requestReservation()

  Attempt to reserve the Status by marking it as committing if it is available. If successful, the caller must subsequently either call `useReservation()` or `commitAndMaybeInvalidate()` (to cancel the reservation).

  This is an internal method.

  Returns:
    true if the reservation was made successfull, false if another thread already owns this Status object

### waitForReservationDecision

    protected void waitForReservationDecision()

  Wait for the Entry that this Status represents to no longer be reserved.

  This is an internal method. It requires the caller to have synchronized on the Status object before calling this method.

### useReservation

    protected MapEvent useReservation()

  After having successfully made a reservation, this method completes the reservation process by setting the status to processing for the thread that made the reservation.

  This is an internal method.

  Returns:
    whatever event was deferred for this Status which the caller must handle

### closeProcessing

    public MapEvent closeProcessing()

  Finish the processing of the entry for which this Status exists and proceed to the commit phase. The act of closing processing collects any side-effects to the corresponding front Map Entry (either from this or other threads) as a single event.

  Returns:
    all events that have occurred on this or other threads for the front Map Entry represented by this Status object while this Status object was "processing", or null if there were no events

### commitAndMaybeInvalidate

    protected boolean commitAndMaybeInvalidate()

  Finish the commit for the entry for which this Status exists. If there are any threads waiting on the entry for which this Status exists, one will be notified that the Status is now available. If the entry for which this Status object exists is contained in the front Map, then it will proceed to the available phase. Otherwise, the Status will be invalidated and discarded from the Status registry.

  This is an internal method. It requires the caller to have first synchronized on the registry (Map) that contains the Status objects and then to have synchronized on this Status object itself, in that explicit order. Failure to follow this rule will result in deadlock and/or exceptional conditions.

  Returns:
    true iff this Status object has invalidated itself

### registerFrontEvent

    public boolean registerFrontEvent(MapEvent evt)

  Register a MapEvent that has been raised by the front Map against the same key for which this Status object exists. If an event has previously been registered, the previous and new event are merged into a single merged event that incorporates the data from both events.

  For truly predictable behavior, this requires that the front Map implementation be synchronized during the raising of events, such that an event will only be raised from the front Map on one thread at a time. The event listener (for the overflow map) must then synchronize on this Status object (to verify that it is indeed valid before registering the event) and the register the event while holding that synchronization. If the registration returns a deferred indicator, then the

  Parameters:
    `evt` - the event that has occurred against an entry in the front Map with the same key which this Status object represents
  Returns:
    true iff the event processing has been deferred, implying that this Status object should be registered in a list of Status objects that have events that need to be handled

### mergeEvents

    protected MapEvent mergeEvents(MapEvent evtOld,
                                   MapEvent evtNew)

  Merge two events that have been raised in sequence from a given map.

  Parameters:
    `evtOld` - the first event
    `evtNew` - the second event
  Returns:
    the merged event

### getState

    protected int getState()

  Determine the state of the Status object. This value is intended for internal and debugging use only, and should have no meaning to any external consumer.

  Returns:
    the bit-packed state of the Status object

### setState

    protected void setState(int nState)

  Specify the state of the Status object. This value is intended for internal and debugging use only, and should have no meaning to any external consumer.

  Parameters:
    `nState` - the new bit-packed state for the Status object

### extractState

    protected int extractState(int nMask)

  Extract a particular masked value from the state of the Status object.

  Parameters:
    `nMask` - the mask identifying the value
  Returns:
    the extracted value

### updateState

    protected void updateState(int nMask,
                               int nValue)

  Update a particular masked value within the state of the Status object.

  Parameters:
    `nMask` - the mask of bits to store the value within
    `nValue` - the value to store inside that mask

### extractFlag

    protected boolean extractFlag(int nMask)

  Extract a particular masked flag from the state of the Status object.

  Parameters:
    `nMask` - the mask identifying the flag
  Returns:
    the extracted flag as a boolean

### updateFlag

    protected void updateFlag(int nMask,
                              boolean f)

  Update a particular masked flag within the state of the Status object.

  Parameters:
    `nMask` - the mask of flag bit to store the flag within
    `f` - the boolean value to store within that mask

Overview | Package | Class | Tree | Index | Help

Oracle® Coherence Java API Reference
v3.5.3
E15583-01
PREV CLASS NEXT CLASS | FRAMES NO FRAMES
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD

Copyright © 2000, 2010, Oracle. All rights reserved.