com.tangosol.util.aggregator

Class ScriptAggregator<K,V,P,R>

java.lang.Object

com.tangosol.util.AbstractScript

com.tangosol.util.aggregator.ScriptAggregator<K,V,P,R>

Type Parameters:

K - the type of the Map entry keys

V - the type of the Map entry values

P - the type of the partial result

R - the type of the final result

All Implemented Interfaces:

ExternalizableLite, PortableObject, SerializationSupport, InvocableMap.EntryAggregator<K,V,R>, InvocableMap.StreamingAggregator<K,V,P,R>, Serializable

public class ScriptAggregator<K,V,P,R>
extends AbstractScript
implements InvocableMap.StreamingAggregator<K,V,P,R>, SerializationSupport

ScriptAggregator is a InvocableMap.StreamingAggregator that wraps a script written in one of the languages supported by Graal VM.

Since:

14.1.1.0

Author:

mk 2019.09.24

Field Summary

Fields inherited from class com.tangosol.util.AbstractScript

m_aoArgs, m_sLanguage, m_sName

Fields inherited from interface com.tangosol.util.InvocableMap.StreamingAggregator

ALLOW_INCONSISTENCIES, BY_MEMBER, BY_PARTITION, PARALLEL, PRESENT_ONLY, RETAINS_ENTRIES, SERIAL

Constructor Summary

Constructors

Constructor and Description
ScriptAggregator() Default constructor for ExternalizableLite.
ScriptAggregator(String language, String name, int characteristics, Object... args) Create a InvocableMap.StreamingAggregator that wraps the specified script.

Method Summary

Modifier and Type	Method and Description
boolean	accumulate(InvocableMap.Entry<? extends K,? extends V> entry) Accumulate one entry into the result.
int	characteristics() A bit mask representing the set of characteristics of this aggregator.
boolean	combine(P partialResult) Merge another partial result into the result.
R	finalizeResult() Return the final result of the aggregation.
P	getPartialResult() Return the partial result of the aggregation.
void	readExternal(DataInput in) Restore the contents of this object by loading the object's state from the passed DataInput object.
void	readExternal(PofReader in) Restore the contents of a user type instance by reading its state using the specified PofReader object.
Object	readResolve() Designate a replacement for an object after an instance of it is read from the buffer.
InvocableMap.StreamingAggregator<K,V,P,R>	supply() Create a new instance of this aggregator.
void	writeExternal(DataOutput out) Save the contents of this object by storing the object's state into the passed DataOutput object.
void	writeExternal(PofWriter out) Save the contents of a POF user type instance by writing its state using the specified PofWriter object.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.tangosol.util.InvocableMap.StreamingAggregator

accumulate, aggregate, isAllowInconsistencies, isByMember, isByPartition, isParallel, isPresentOnly, isRetainsEntries, isSerial

Methods inherited from interface com.tangosol.io.SerializationSupport

writeReplace

Constructor Detail

ScriptAggregator

public ScriptAggregator()

Default constructor for ExternalizableLite.

ScriptAggregator

public ScriptAggregator(String language,
                        String name,
                        int characteristics,
                        Object... args)

Create a InvocableMap.StreamingAggregator that wraps the specified script.

Parameters:

language - the language the script is written.

name - the name of the Filter that needs to be evaluated

characteristics - a bit mask representing the set of characteristics of this aggregator

args - the arguments to be passed to the script during evaluation

Method Detail

characteristics

public int characteristics()

Description copied from interface: InvocableMap.StreamingAggregator

A bit mask representing the set of characteristics of this aggregator.

Be default, characteristics are a combination of InvocableMap.StreamingAggregator.PARALLEL and InvocableMap.StreamingAggregator.RETAINS_ENTRIES, which is sub-optimal and should be overridden by the aggregator implementation if the aggregator does not need to retain entries (which is often the case).

Specified by:

characteristics in interface InvocableMap.StreamingAggregator<K,V,P,R>

Returns:

a bit mask representing the set of characteristics of this aggregator

See Also:

InvocableMap.StreamingAggregator.PARALLEL, InvocableMap.StreamingAggregator.SERIAL, InvocableMap.StreamingAggregator.BY_MEMBER, InvocableMap.StreamingAggregator.BY_PARTITION, InvocableMap.StreamingAggregator.RETAINS_ENTRIES, InvocableMap.StreamingAggregator.PRESENT_ONLY

supply

public InvocableMap.StreamingAggregator<K,V,P,R> supply()

Description copied from interface: InvocableMap.StreamingAggregator

Create a new instance of this aggregator.

Specified by:

supply in interface InvocableMap.StreamingAggregator<K,V,P,R>

Returns:

a StreamAggregator

accumulate

public boolean accumulate(InvocableMap.Entry<? extends K,? extends V> entry)

Description copied from interface: InvocableMap.StreamingAggregator

Accumulate one entry into the result.

Specified by:

accumulate in interface InvocableMap.StreamingAggregator<K,V,P,R>

Parameters:

entry - the entry to accumulate into the aggregation result

Returns:

true to continue the aggregation, and false to signal to the caller that the result is ready and the aggregation can be short-circuited

combine

public boolean combine(P partialResult)

Description copied from interface: InvocableMap.StreamingAggregator

Merge another partial result into the result.

Specified by:

combine in interface InvocableMap.StreamingAggregator<K,V,P,R>

Parameters:

partialResult - the partial result to merge

Returns:

true to continue the aggregation, and false to signal to the caller that the result is ready and the aggregation can be short-circuited

getPartialResult

public P getPartialResult()

Description copied from interface: InvocableMap.StreamingAggregator

Return the partial result of the aggregation.

Specified by:

getPartialResult in interface InvocableMap.StreamingAggregator<K,V,P,R>

Returns:

the partial result of the aggregation

finalizeResult

public R finalizeResult()

Description copied from interface: InvocableMap.StreamingAggregator

Return the final result of the aggregation.

Specified by:

finalizeResult in interface InvocableMap.StreamingAggregator<K,V,P,R>

Returns:

the final result of the aggregation

readExternal

public void readExternal(PofReader in)
                  throws IOException

Description copied from interface: PortableObject

Restore the contents of a user type instance by reading its state using the specified PofReader object.

Specified by:

readExternal in interface PortableObject

Overrides:

readExternal in class AbstractScript

Parameters:

in - the PofReader from which to read the object's state

Throws:

IOException - if an I/O error occurs

writeExternal

public void writeExternal(PofWriter out)
                   throws IOException

Description copied from interface: PortableObject

Save the contents of a POF user type instance by writing its state using the specified PofWriter object.

Specified by:

writeExternal in interface PortableObject

Overrides:

writeExternal in class AbstractScript

Parameters:

out - the PofWriter to which to write the object's state

Throws:

IOException - if an I/O error occurs

readExternal

public void readExternal(DataInput in)
                  throws IOException

Description copied from interface: ExternalizableLite

Restore the contents of this object by loading the object's state from the passed DataInput object.

Specified by:

readExternal in interface ExternalizableLite

Overrides:

readExternal in class AbstractScript

Parameters:

in - the DataInput stream to read data from in order to restore the state of this object

Throws:

IOException - if an I/O exception occurs

NotActiveException - if the object is not in its initial state, and therefore cannot be deserialized into

writeExternal

public void writeExternal(DataOutput out)
                   throws IOException

Description copied from interface: ExternalizableLite

Save the contents of this object by storing the object's state into the passed DataOutput object.

Specified by:

writeExternal in interface ExternalizableLite

Overrides:

writeExternal in class AbstractScript

Parameters:

out - the DataOutput stream to write the state of this object to

Throws:

IOException - if an I/O exception occurs

readResolve

public Object readResolve()
                   throws ObjectStreamException

Description copied from interface: SerializationSupport

Designate a replacement for an object after an instance of it is read from the buffer.

This method is invoked by the Serializer if the object implements SerializationSupport interface.

Specified by:

readResolve in interface SerializationSupport

Returns:

an object that should be returned instead of the deserialized one

Throws:

ObjectStreamException