com.tangosol.util.processor

Class PreloadRequest<K,V>

java.lang.Object

com.tangosol.util.Base

com.tangosol.util.processor.AbstractProcessor<K,V,V>

com.tangosol.util.processor.PreloadRequest<K,V>

All Implemented Interfaces:

ExternalizableLite, PortableObject, InvocableMap.EntryProcessor<K,V,V>, Serializable

public class PreloadRequest<K,V>
extends AbstractProcessor<K,V,V>
implements ExternalizableLite, PortableObject

PreloadRequest is a simple EntryProcessor that performs a Entry.getValue call. No results are reported back to the caller.

The PreloadRequest process provides a means to "pre-load" an entry or a collection of entries into the cache using the cache loader without incurring the cost of sending the value(s) over the network. If the corresponding entry (or entries) already exists in the cache, or if the cache does not have a loader, then invoking this EntryProcessor has no effect.

Since:

Coherence 3.2

Author:

gg 2006.04.28

Nested Class Summary

Nested classes/interfaces inherited from class com.tangosol.util.Base

Base.LoggingWriter, Base.StackFrame

Field Summary

Fields

Modifier and Type	Field and Description
static PreloadRequest	INSTANCE An instance of the PreloadRequest processor.

Fields inherited from class com.tangosol.util.Base

LOG_ALWAYS, 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

Constructor Summary

Constructors

Constructor and Description
PreloadRequest() Construct the PreloadRequest processor.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object o) Compare the PreloadRequest with another object to determine equality.
int	hashCode() Determine a hash value for the PreloadRequest object according to the general Object.hashCode() contract.
static <K,V> PreloadRequest<K,V>	INSTANCE() Return an instance of the PreloadRequest processor.
V	process(InvocableMap.Entry<K,V> entry) Process a Map.Entry object.
Map<K,V>	processAll(Set<? extends InvocableMap.Entry<K,V>> setEntries) Process a Set of InvocableMap.Entry objects.
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.
String	toString() Return a human-readable description for this PreloadRequest processor.
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 com.tangosol.util.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, getThreadFactory, getTimeZone, getUpTimeMillis, hashCode, hexValue, indentString, indentString, isDecimal, isHex, isLogEcho, isOctal, log, log, log, log, log, makeInteger, makeLong, makeThread, mod, mod, 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 java.lang.Object

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

Field Detail

INSTANCE

public static final PreloadRequest INSTANCE

An instance of the PreloadRequest processor.

Constructor Detail

PreloadRequest

public PreloadRequest()

Construct the PreloadRequest processor.

Method Detail

process

public V process(InvocableMap.Entry<K,V> entry)

Process a Map.Entry object.

Note: if this method throws an exception, all modifications to the supplied entry or any other entries retrieved via the BackingMapContext.getBackingMapEntry(java.lang.Object) API will be rolled back leaving all underlying values unchanged.

Specified by:

process in interface InvocableMap.EntryProcessor<K,V,V>

Parameters:

entry - the Entry to process

Returns:

the result of the processing, if any

processAll

public Map<K,V> processAll(Set<? extends InvocableMap.Entry<K,V>> setEntries)

Process a Set of InvocableMap.Entry objects. This method is semantically equivalent to:

   Map mapResults = new ListMap();
   for (Iterator iter = setEntries.iterator(); iter.hasNext(); )
       {
       Entry entry = (Entry) iter.next();
       mapResults.put(entry.getKey(), process(entry));
       }
   return mapResults;
 

Note: if processAll() call throws an exception, only the entries that were removed from the setEntries would be considered successfully processed and the corresponding changes made to the underlying Map; changes made to the remaining entries or any other entries obtained from BackingMapContext.getBackingMapEntry(java.lang.Object) will not be processed. Note: As of Coherence 12.2.1, this method simply delegates to the default processAll implementation in InvocableMap.EntryProcessor.

Specified by:

processAll in interface InvocableMap.EntryProcessor<K,V,V>

Overrides:

processAll in class AbstractProcessor<K,V,V>

Parameters:

setEntries - a Set of InvocableMap.Entry objects to process

Returns:

a Map containing the results of the processing, up to one entry for each InvocableMap.Entry that was processed, keyed by the keys of the Map that were processed, with a corresponding value being the result of the processing for each key

equals

public boolean equals(Object o)

Compare the PreloadRequest with another object to determine equality.

Overrides:

equals in class Object

Returns:

true iff this PreloadRequest and the passed object are equivalent PreloadRequest objects

hashCode

public int hashCode()

Determine a hash value for the PreloadRequest object according to the general Object.hashCode() contract.

Overrides:

hashCode in class Object

Returns:

an integer hash value for this ConditionalPut object

toString

public String toString()

Return a human-readable description for this PreloadRequest processor.

Overrides:

toString in class Object

Returns:

a String description of the PreloadRequest processor

readExternal

public void readExternal(DataInput in)
                  throws IOException

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

Specified by:

readExternal in interface ExternalizableLite

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

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

Specified by:

writeExternal in interface ExternalizableLite

Parameters:

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

Throws:

IOException - if an I/O exception occurs

readExternal

public void readExternal(PofReader in)
                  throws IOException

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

Specified by:

readExternal in interface PortableObject

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

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

Specified by:

writeExternal in interface PortableObject

Parameters:

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

Throws:

IOException - if an I/O error occurs

INSTANCE

public static <K,V> PreloadRequest<K,V> INSTANCE()

Return an instance of the PreloadRequest processor.

Type Parameters:

K - the key type

V - the value type

Returns:

a PreloadRequest