org.infinispan.commands.write

Class RemoveCommand

java.lang.Object

org.infinispan.commands.AbstractLocalFlagAffectedCommand

org.infinispan.commands.AbstractFlagAffectedCommand

org.infinispan.commands.read.AbstractDataCommand

org.infinispan.commands.write.AbstractDataWriteCommand

org.infinispan.commands.write.RemoveCommand

All Implemented Interfaces:

DataCommand, FlagAffectedCommand, LocalFlagAffectedCommand, MetadataAwareCommand, ReplicableCommand, TopologyAffectedCommand, VisitableCommand, DataWriteCommand, WriteCommand, RemoteLockCommand

Direct Known Subclasses:

EvictCommand, InvalidateCommand, RemoveExpiredCommand

public class RemoveCommand
extends AbstractDataWriteCommand

Since:

4.0

Author:

Mircea.Markus@jboss.com, Galder Zamarreno

Field Summary

Fields

Modifier and Type	Field and Description
static byte	COMMAND_ID
protected CacheNotifier	notifier
protected Object	value When not null, value indicates that the entry should only be removed if the key is mapped to this value.
protected Equivalence	valueEquivalence
protected ValueMatcher	valueMatcher

Fields inherited from class org.infinispan.commands.write.AbstractDataWriteCommand

commandInvocationId

Fields inherited from class org.infinispan.commands.read.AbstractDataCommand

key

Fields inherited from class org.infinispan.commands.AbstractLocalFlagAffectedCommand

flags

Constructor Summary

Constructors

Constructor and Description
RemoveCommand()
RemoveCommand(Object key, Object value, CacheNotifier notifier, Set<Flag> flags, Equivalence valueEquivalence, CommandInvocationId commandInvocationId)

Method Summary

Modifier and Type	Method and Description
Object	acceptVisitor(InvocationContext ctx, Visitor visitor) Accept a visitor, and return the result of accepting this visitor.
boolean	equals(Object o)
byte	getCommandId() Used by marshallers to convert this command into an id for streaming.
Object	getValue()
ValueMatcher	getValueMatcher()
int	hashCode()
boolean	ignoreCommandOnStatus(ComponentStatus status) Similar to VisitableCommand.shouldInvoke(InvocationContext) but evaluated by InvocationContextInterceptor.
void	init(CacheNotifier notifier, Configuration configuration)
boolean	isConditional() Certain commands only work based on a certain condition or state of the cache.
boolean	isNonExistent()
boolean	isReturnValueExpected() If true, a return value will be provided when performed remotely.
boolean	isSuccessful() Some commands may want to provide information on whether the command was successful or not.
void	notify(InvocationContext ctx, Object removedValue, Metadata removedMetadata, boolean isPre)
Object	perform(InvocationContext ctx) Performs the primary function of the command.
protected Object	performRemove(CacheEntry e, InvocationContext ctx)
void	readFrom(ObjectInput input) Reads this instance from the stream written by ReplicableCommand.writeTo(ObjectOutput).
boolean	readsExistingValues()
void	setValue(Object value)
void	setValueMatcher(ValueMatcher valueMatcher)
String	toString()
void	updateStatusFromRemoteResponse(Object remoteResponse) Used for conditional commands, to update the status of the command on the originator based on the result of its execution on the primary owner.
void	writeTo(ObjectOutput output) Writes this instance to the ObjectOutput.

Methods inherited from class org.infinispan.commands.write.AbstractDataWriteCommand

canBlock, getAffectedKeys, getKeyLockOwner, getKeysToLock, hasSkipLocking, hasZeroLockAcquisition

Methods inherited from class org.infinispan.commands.read.AbstractDataCommand

getKey, setKey, shouldInvoke

Methods inherited from class org.infinispan.commands.AbstractFlagAffectedCommand

getMetadata, getTopologyId, setMetadata, setTopologyId

Methods inherited from class org.infinispan.commands.AbstractLocalFlagAffectedCommand

getFlags, setFlags

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.infinispan.commands.write.WriteCommand

isWriteOnly

Methods inherited from interface org.infinispan.commands.VisitableCommand

alwaysReadsExistingValues, shouldInvoke

Methods inherited from interface org.infinispan.commands.TopologyAffectedCommand

getTopologyId, setTopologyId

Methods inherited from interface org.infinispan.commands.ReplicableCommand

getParameters, setParameters

Methods inherited from interface org.infinispan.commands.MetadataAwareCommand

getMetadata, setMetadata

Methods inherited from interface org.infinispan.commands.LocalFlagAffectedCommand

addFlag, addFlags, getFlags, hasFlag, setFlags, setFlags

Methods inherited from interface org.infinispan.commands.DataCommand

getKey

Field Detail

COMMAND_ID

public static final byte COMMAND_ID

See Also:

Constant Field Values

notifier

protected CacheNotifier notifier

valueMatcher

protected ValueMatcher valueMatcher

valueEquivalence

protected Equivalence valueEquivalence

value

protected Object value

When not null, value indicates that the entry should only be removed if the key is mapped to this value. When null, the entry should be removed regardless of what value it is mapped to.

Constructor Detail

RemoveCommand

public RemoveCommand(Object key,
                     Object value,
                     CacheNotifier notifier,
                     Set<Flag> flags,
                     Equivalence valueEquivalence,
                     CommandInvocationId commandInvocationId)

RemoveCommand

public RemoveCommand()

Method Detail

init

public void init(CacheNotifier notifier,
                 Configuration configuration)

acceptVisitor

public Object acceptVisitor(InvocationContext ctx,
                            Visitor visitor)
                     throws Throwable

Description copied from interface: VisitableCommand

Accept a visitor, and return the result of accepting this visitor.

Parameters:

ctx - invocation context

visitor - visitor to accept

Returns:

arbitrary return value

Throws:

Throwable - in the event of problems

perform

public Object perform(InvocationContext ctx)
               throws Throwable

Description copied from interface: ReplicableCommand

Performs the primary function of the command. Please see specific implementation classes for details on what is performed as well as return types. Important: this method will be invoked at the end of interceptors chain. It should never be called directly from a custom interceptor.

Parameters:

ctx - invocation context

Returns:

arbitrary return value generated by performing this command

Throws:

Throwable - in the event of problems.

notify

public void notify(InvocationContext ctx,
                   Object removedValue,
                   Metadata removedMetadata,
                   boolean isPre)

getCommandId

public byte getCommandId()

Description copied from interface: ReplicableCommand

Used by marshallers to convert this command into an id for streaming.

Returns:

the method id of this command. This is compatible with pre-2.2.0 MethodCall ids.

equals

public boolean equals(Object o)

Overrides:

equals in class AbstractDataCommand

hashCode

public int hashCode()

Overrides:

hashCode in class AbstractDataCommand

toString

public String toString()

Overrides:

toString in class AbstractDataCommand

isSuccessful

public boolean isSuccessful()

Description copied from interface: WriteCommand

Some commands may want to provide information on whether the command was successful or not. This is different from a failure, which usually would result in an exception being thrown. An example is a putIfAbsent() not doing anything because the key in question was present. This would result in a isSuccessful() call returning false.

Returns:

true if the command completed successfully, false otherwise.

isConditional

public boolean isConditional()

Description copied from interface: WriteCommand

Certain commands only work based on a certain condition or state of the cache. For example, ConcurrentMap.putIfAbsent(Object, Object) only does anything if a condition is met, i.e., the entry in question is not already present. This method tests whether the command in question is conditional or not.

Returns:

true if the command is conditional, false otherwise

isNonExistent

public boolean isNonExistent()

writeTo

public void writeTo(ObjectOutput output)
             throws IOException

Description copied from interface: ReplicableCommand

Writes this instance to the ObjectOutput.

Parameters:

output - the stream.

Throws:

IOException - if an error occurred during the I/O.

readFrom

public void readFrom(ObjectInput input)
              throws IOException,
                     ClassNotFoundException

Description copied from interface: ReplicableCommand

Reads this instance from the stream written by ReplicableCommand.writeTo(ObjectOutput).

Parameters:

input - the stream to read.

Throws:

IOException - if an error occurred during the I/O.

ClassNotFoundException - if it tries to load an undefined class.

getValueMatcher

public ValueMatcher getValueMatcher()

Returns:

The current value matching policy.

setValueMatcher

public void setValueMatcher(ValueMatcher valueMatcher)

Parameters:

valueMatcher - The new value matching policy.

updateStatusFromRemoteResponse

public void updateStatusFromRemoteResponse(Object remoteResponse)

Description copied from interface: WriteCommand

Used for conditional commands, to update the status of the command on the originator based on the result of its execution on the primary owner.

ignoreCommandOnStatus

public boolean ignoreCommandOnStatus(ComponentStatus status)

Description copied from interface: VisitableCommand

Similar to VisitableCommand.shouldInvoke(InvocationContext) but evaluated by InvocationContextInterceptor. Commands can opt to be discarded in case the cache status is not suited (as InvalidateCommand)

Specified by:

ignoreCommandOnStatus in interface VisitableCommand

Overrides:

ignoreCommandOnStatus in class AbstractDataCommand

Returns:

true if the command should NOT be invoked.

readsExistingValues

public boolean readsExistingValues()

Returns:

true if the command needs to read the previous values of the keys it acts on.

getValue

public Object getValue()

setValue

public void setValue(Object value)

isReturnValueExpected

public final boolean isReturnValueExpected()

Description copied from interface: ReplicableCommand

If true, a return value will be provided when performed remotely. Otherwise, a remote ResponseGenerator may choose to simply return null to save on marshalling costs.

Specified by:

isReturnValueExpected in interface ReplicableCommand

Overrides:

isReturnValueExpected in class AbstractDataWriteCommand

Returns:

true or false

performRemove

protected Object performRemove(CacheEntry e,
                               InvocationContext ctx)