Class DoubleAverage<T>

java.lang.Object

com.tangosol.util.Base

com.tangosol.util.BitHelper

com.tangosol.util.ExternalizableHelper

com.tangosol.util.aggregator.AbstractAggregator<Object,Object,T,Number,Double>

com.tangosol.util.aggregator.AbstractDoubleAggregator<T>

com.tangosol.util.aggregator.DoubleAverage<T>

Type Parameters:

T - the type of the value to extract from

All Implemented Interfaces:

ExternalizableLite, PortableObject, InvocableMap.EntryAggregator<Object,Object,Double>, InvocableMap.StreamingAggregator<Object,Object,Object,Double>, Serializable, Cloneable

public class DoubleAverage<T>
extends AbstractDoubleAggregator<T>

Calculates an average for values of any numeric type extracted from a set of entries in a Map. All the extracted Number objects will be treated as Java double values. If the set of entries is empty, a null result is returned.

Since:

Coherence 3.1

Author:

gg 2005.09.05

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class ExternalizableHelper

ExternalizableHelper.DecoratedMultiBufferReadBuffer, ExternalizableHelper.DecorationAware, ExternalizableHelper.DefaultObjectStreamFactory, ExternalizableHelper.FormatAwareCompressor, ExternalizableHelper.IntDecoratedObject, ExternalizableHelper.Shielded, ExternalizableHelper.ShieldedDataOutputStream, ExternalizableHelper.ShieldedInputStream, ExternalizableHelper.ShieldedObjectOutputStream, ExternalizableHelper.ShieldedOutputStream, ExternalizableHelper.SimpleXmlBeanClassCache, ExternalizableHelper.Stats, ExternalizableHelper.XmlBeanClassCache

Nested classes/interfaces inherited from class Base

Base.LoggingWriter

Nested classes/interfaces inherited from interface InvocableMap.StreamingAggregator

InvocableMap.StreamingAggregator.RetractionResult

Field Summary

Fields inherited from class AbstractDoubleAggregator

m_count, m_dflResult

Fields inherited from class AbstractAggregator

m_fParallel

Fields inherited from class ExternalizableHelper

BINARY_SIZE, CHUNK_SIZE, CHUNK_THRESHOLD, CONVERTER_FROM_BINARY, CONVERTER_STRIP_INTDECO, CONVERTER_TO_BINARY, DECO_APP_1, DECO_APP_2, DECO_APP_3, DECO_BACKUP, DECO_CUSTOM, DECO_EXPIRY, DECO_ID_MAX, DECO_ID_MIN, DECO_JCACHE, DECO_JCACHE_SYNTHETIC, DECO_MEMCACHED, DECO_PUSHREP, DECO_RSVD_1, DECO_STORE, DECO_TOPLINK, DECO_TX, DECO_VALUE, DECO_VECTOR, DECO_WLS, EMPTY_BINARY_ARRAY, FMT_B_ARRAY, FMT_BIN_DECO, FMT_BIN_EXT_DECO, FMT_BINARY, FMT_BOOLEAN, FMT_BYTE, FMT_DECIMAL, FMT_DOUBLE, FMT_EXT, FMT_FLOAT, FMT_IDO, FMT_INT, FMT_INTEGER, FMT_LONG, FMT_NONE, FMT_NULL, FMT_OBJ_EXT, FMT_OBJ_SER, FMT_OPT, FMT_OPT_DOUBLE, FMT_OPT_INT, FMT_OPT_LONG, FMT_SHORT, FMT_STRING, FMT_UNKNOWN, FMT_XML_BEAN, FMT_XML_SER, FORCE_RESOLVING_STREAMS, LAMBDA_SERIALIZATION, MAX_DECO_HEADER_BYTES, MAX_MEMCACHED_PASS_THROUGH_FORMAT_DEPTH, PACKED_INT_SIZE, PACKED_LONG_SIZE, PROPERTY_CONFIG, s_streamfactory, s_tloInEHDeserialize, TRINT_DOMAIN_SPAN, TRINT_MAX_VALUE, TRINT_MAX_VARIANCE, USE_POF_STREAMS, USE_XMLBEAN_CLASS_CACHE, XMLBEAN_CLASS_CACHE

Fields inherited from class Base

DEFAULT_LOAD_FACTOR, LOG_ALWAYS, LOG_CONFIG, LOG_DEBUG, LOG_ERR, LOG_INFO, LOG_MAX, LOG_MIN, LOG_QUIET, LOG_WARN, POWER_0, POWER_G, POWER_K, POWER_M, POWER_T, UNIT_D, UNIT_H, UNIT_M, UNIT_MS, UNIT_NS, UNIT_S, UNIT_US

Fields inherited from interface InvocableMap.StreamingAggregator

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

Constructor Summary

Constructors

Constructor	Description
DoubleAverage()	Default constructor (necessary for the ExternalizableLite interface).
DoubleAverage(ValueExtractor<? super T, ? extends Number> extractor)	Construct a DoubleAverage aggregator.
DoubleAverage(String sMethod)	Construct an DoubleAverage object.

Method Summary

Modifier and Type	Method	Description
int	characteristics()	A bit mask representing the set of characteristics of this aggregator.
protected Object	finalizeResult(boolean fFinal)	Obtain the result of the aggregation.
protected void	init(boolean fFinal)	Initialize the aggregation result.
protected boolean	isReplacementRequired(Object oOriginal, Object oCurrent)	Return whether an extracted value replacement needs to be applied.
protected void	process(Object o, boolean fFinal)	Incorporate one aggregatable value into the result.
protected InvocableMap.StreamingAggregator.RetractionResult	remove(Object o)	Remove one extracted value from the aggregation result.
protected InvocableMap.StreamingAggregator.RetractionResult	replace(Object oOriginal, Object oCurrent)	Replace one extracted value in the aggregation result.
InvocableMap.StreamingAggregator<Object,Object,Object,Double>	supply()	Create a new instance of this aggregator.

Methods inherited from class AbstractDoubleAggregator

restoreState, snapshotState

Methods inherited from class AbstractAggregator

accumulate, accumulate, combine, ensureInitialized, equals, finalizeResult, getPartialResult, getValueExtractor, hashCode, processEntry, readExternal, readExternal, retract, toString, update, writeExternal, writeExternal

Methods inherited from class ExternalizableHelper

asBinary, calculatePackedLength, calculatePackedLength, checkObjectInputFilter, checkObjectInputFilter, checkObjectInputFilter, convertUTF, decodeExpiry, decorate, decorate, decorate, decorate, decorate, decorateBinary, encodeExpiry, ensureSerializer, extractIntDecoration, fromBinary, fromBinary, fromBinary, fromBinary, fromBinary, fromBinary, fromByteArray, fromByteArray, getClass, getConfigSerialFilter, getConfigSerialFilterFactory, getDecoration, getDecoration, getDecorations, getDeltaCompressor, getInputStream, getNewObjectInput, getObjectInput, getObjectInputFilter, getObjectOutput, getObjectStreamFactory, getOutputStream, getShieldedOutputStream, getStreamFormat, getUndecorated, getUndecorated, isDecorated, isDecorated, isIntDecorated, isIntDecorated, isPatchCompatible, isPatchCompatible, isResolving, isSerializable, isSerializerCompatible, isVersionCompatible, isVersionCompatible, isVersionCompatible, isVersionCompatible, isVersionCompatible, isVersionCompatible, isVersionCompatible, isVersionCompatible, loadClass, loadResource, main, makeTrint, newFilteredObjectInputStream, newFilteredObjectInputStream, readBigDecimal, readBigInteger, readBooleanArray, readBooleanArray, readByteArray, readCharArray, readCharArray, readCollection, readDate, readDoubleArray, readDoubleArray, readExternalizableLite, readExternalizableLite, readFloatArray, readFloatArray, readInt, readInt, readIntArray, readIntArray, readIntArray2d, readLargeBooleanArray, readLargeByteArray, readLargeCharArray, readLargeDoubleArray, readLargeFloatArray, readLargeIntArray, readLargeLongArray, readLargeObjectArray, readLargeStringArray, readLong, readLong, readLongArray, readLongArray, readMap, readMap, readObject, readObject, readObjectArray, readObjectArray, readSafeUTF, readSafeUTF, readSerializable, readSerializable, readStringArray, readStringArray, readTime, readTimestamp, readTrint, readUnsignedTrint, readUTF, readXmlBean, readXmlSerializable, readXmlSerializable, realize, removeIntDecoration, removeIntDecoration, replace, reportIncompatibleSerializers, reportIncompatibleSerializers, reportIncompatibleSerializers, reportIncompatibleSerializers, setObjectStreamFactory, toBinary, toBinary, toBinary, toByteArray, toByteArray, toByteArray, toLiteBinary, toLong, undecorate, undecorate, validateBufferSize, validateLoadArray, validateLoadClass, validateMemcachedPassThroughValue, validateMemcachedPassThroughValue, validateMemcachedPassThroughValue, validateMemcachedPassThroughValue, writeBigDecimal, writeBigInteger, writeBooleanArray, writeByteArray, writeCollection, writeDate, writeDoubleArray, writeExternalizableLite, writeFloatArray, writeInt, writeInt, writeIntArray, writeIntArray2d, writeLong, writeLong, writeLongArray, writeMap, writeObject, writeSafeUTF, writeSafeUTF, writeSerializable, writeStringArray, writeTime, writeTimestamp, writeTrint, writeTrint, writeUTF, writeXmlBean, writeXmlSerializable

Methods inherited from class BitHelper

countBits, countBits, countBits, indexOfLSB, indexOfLSB, indexOfLSB, indexOfMSB, indexOfMSB, indexOfMSB, rotateLeft, rotateLeft, rotateLeft, rotateRight, rotateRight, rotateRight, toBitString, toBitString, toBitString, toBytes, toBytes, toBytes, toBytes, toInt, toInt, toLong

Methods inherited from class Base

azzert, azzert, azzert, azzertFailed, breakLines, breakLines, capitalize, checkNotEmpty, checkNotNull, checkRange, computeSafeWaitTime, decimalValue, dup, dup, ensureBigDecimal, ensureClassLoader, ensureRuntimeException, ensureRuntimeException, equals, equalsDeep, err, err, err, err, err, escape, formatDateTime, getCallerStackFrame, getCommonMonitor, getCommonMonitor, getCommonMonitor, getContextClassLoader, getContextClassLoader, getDeepMessage, getErr, getLastSafeTimeMillis, getLog, getMaxDecDigits, getMaxHexDigits, getOriginalException, getOut, getProcessRandom, getRandom, getRandomBinary, getRandomBinary, getRandomString, getSafeTimeMillis, getStackFrame, getStackFrames, getStackTrace, getStackTrace, getStackTrace, getThreadFactory, getTimeZone, getUpTimeMillis, hashCode, hexValue, indentString, indentString, isDecimal, isHex, isLogEcho, isOctal, log, log, log, log, log, makeInteger, makeLong, makeThread, mergeArray, mergeBooleanArray, mergeByteArray, mergeCharArray, mergeDoubleArray, mergeFloatArray, mergeIntArray, mergeLongArray, mod, mod, newHashMap, newHashMap, newHashSet, newHashSet, octalValue, out, out, out, out, out, pad, parseBandwidth, parseBandwidth, parseDelimitedString, parseHex, parseHex, parseMemorySize, parseMemorySize, parsePercentage, parseTime, parseTime, parseTimeNanos, parseTimeNanos, printStackTrace, randomize, randomize, randomize, randomize, read, read, read, read, read, read, read, replace, setErr, setLog, setLogEcho, setOut, sleep, toBandwidthString, toBandwidthString, toCharEscape, toCrc, toCrc, toCrc, toCrc, toCrc, toDecString, toDelimitedString, toDelimitedString, toDelimitedString, toDelimitedString, toHex, toHex, toHexDump, toHexEscape, toHexEscape, toHexEscape, toHexEscape, toHexString, toMemorySizeString, toMemorySizeString, toQuotedCharEscape, toQuotedStringEscape, toSqlString, toString, toString, toStringEscape, toUnicodeEscape, trace, trace, trace, trace, trace, trace, trace, trace, trace, truncateString, truncateString, wait

Methods inherited from class Object

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

Methods inherited from interface InvocableMap.StreamingAggregator

aggregate, finalizeResult, getMaintenanceStatus, isAllowInconsistencies, isByMember, isByPartition, isContinuous, isParallel, isPresentOnly, isRetainsEntries, isSerial, isStateCheckpointable

Constructor Details

DoubleAverage

public DoubleAverage()

Default constructor (necessary for the ExternalizableLite interface).

DoubleAverage

public DoubleAverage(ValueExtractor<? super T, ? extends Number> extractor)

Construct a DoubleAverage aggregator.

Parameters:

extractor - the extractor that provides a value in the form of any Java object that is a Number

DoubleAverage

public DoubleAverage(String sMethod)

Construct an DoubleAverage object.

Parameters:

sMethod - the name of the method that returns a value in the form of any Java object that is a Number

Method Details

supply

public InvocableMap.StreamingAggregator<Object,Object,Object,Double> supply()

Description copied from interface: InvocableMap.StreamingAggregator

Create a new instance of this aggregator.

Specified by:

supply in interface InvocableMap.StreamingAggregator<Object,Object,Object,Double>

Overrides:

supply in class AbstractAggregator<Object,Object,T,Number,Double>

Returns:

a StreamAggregator

characteristics

public int characteristics()

Description copied from interface: InvocableMap.StreamingAggregator

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

By 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).

Returns:

a bit mask representing the set of characteristics of this aggregator

See Also:

• InvocableMap.StreamingAggregator.ALLOW_INCONSISTENCIES
• InvocableMap.StreamingAggregator.BY_MEMBER
• InvocableMap.StreamingAggregator.BY_PARTITION
• InvocableMap.StreamingAggregator.CONTINUOUS
• InvocableMap.StreamingAggregator.STATE_CHECKPOINTABLE
• InvocableMap.StreamingAggregator.PARALLEL
• InvocableMap.StreamingAggregator.PRESENT_ONLY
• InvocableMap.StreamingAggregator.RETAINS_ENTRIES
• InvocableMap.StreamingAggregator.SERIAL

init

protected void init(boolean fFinal)

Initialize the aggregation result.

Overrides:

init in class AbstractDoubleAggregator<T>

Parameters:

fFinal - true is passed if the aggregation process that is being initialized must produce a final aggregation result; this will only be false if a parallel approach is being used and the initial (partial) aggregation process is being initialized

process

protected void process(Object o,
 boolean fFinal)

Incorporate one aggregatable value into the result.

If the fFinal parameter is true, the given object is a partial result (returned by an individual parallel aggregator) that should be incorporated into the final result; otherwise, the object is a value extracted from an InvocableMap.Entry.

Specified by:

process in class AbstractAggregator<Object,Object,T,Number,Double>

Parameters:

o - the value to incorporate into the aggregated result

fFinal - true to indicate that the given object is a partial result returned by a parallel aggregator

remove

protected InvocableMap.StreamingAggregator.RetractionResult remove(Object o)

Remove one extracted value from the aggregation result.

Overrides:

remove in class AbstractAggregator<Object,Object,T,Number,Double>

Parameters:

o - the extracted value to remove

Returns:

the state of the aggregation result after the removal

replace

protected InvocableMap.StreamingAggregator.RetractionResult replace(Object oOriginal,
 Object oCurrent)

Description copied from class: AbstractAggregator

Replace one extracted value in the aggregation result.

Overrides:

replace in class AbstractAggregator<Object,Object,T,Number,Double>

Parameters:

oOriginal - the original extracted value

oCurrent - the current extracted value

Returns:

the state of the aggregation result after the replacement

isReplacementRequired

protected boolean isReplacementRequired(Object oOriginal,
 Object oCurrent)

Description copied from class: AbstractAggregator

Return whether an extracted value replacement needs to be applied.

Overrides:

isReplacementRequired in class AbstractAggregator<Object,Object,T,Number,Double>

Parameters:

oOriginal - the original extracted value

oCurrent - the current extracted value

Returns:

true if the replacement should be applied

finalizeResult

protected Object finalizeResult(boolean fFinal)

Obtain the result of the aggregation.

If the fFinal parameter is true, the returned object must be the final result of the aggregation; otherwise, the returned object will be treated as a partial result that should be incorporated into the final result.

Overrides:

finalizeResult in class AbstractDoubleAggregator<T>

Parameters:

fFinal - true to indicate that the final result of the aggregation process should be returned; this will only be false if a parallel approach is being used

Returns:

the result of the aggregation process