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/*
* Copyright (c) 2000, 2020, Oracle and/or its affiliates.
*
* Licensed under the Universal Permissive License v 1.0 as shown at
* http://oss.oracle.com/licenses/upl.
*/
package com.tangosol.util;
import com.oracle.coherence.common.base.Logger;
import com.tangosol.net.BackingMapContext;
import com.tangosol.net.cache.ConfigurableCacheMap;
import com.tangosol.net.cache.ConfigurableCacheMap.UnitCalculator;
import com.tangosol.net.cache.ReadWriteBackingMap;
import com.tangosol.net.cache.SimpleMemoryCalculator;
import com.tangosol.util.comparator.SafeComparator;
import com.tangosol.util.extractor.AbstractExtractor;
import com.tangosol.util.extractor.KeyExtractor;
import com.tangosol.util.extractor.MultiExtractor;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
/**
* SimpleMapIndex is a MapIndex implementation used to correlate property values
* extracted from resource map entries with corresponding keys using what is
* commonly known as an Inverted Index algorithm.
*
* @author tb 2009.03.19
* @since Coherence 3.5
*/
public class SimpleMapIndex
extends Base
implements MapIndex
{
// ----- constructors ---------------------------------------------------
/**
* Construct an index for the given map.
*
* @param extractor the ValueExtractor that is used to extract an indexed
* value from a resource map entry
* @param fOrdered true iff the contents of the indexed information
* should be ordered; false otherwise
* @param comparator the Comparator object which imposes an ordering
* on entries in the index map; or null
* if the entries' values natural ordering should be used
* @param ctx the {@link BackingMapContext context} associated with
* the indexed cache
*/
public SimpleMapIndex(ValueExtractor extractor, boolean fOrdered,
Comparator comparator, BackingMapContext ctx)
{
this(extractor, fOrdered, comparator, true, ctx);
}
/**
* Construct an index for the given map.
*
* @param extractor the ValueExtractor that is used to extract an indexed
* value from a resource map entry
* @param fOrdered true iff the contents of the indexed information
* should be ordered; false otherwise
* @param comparator the Comparator object which imposes an ordering
* on entries in the index map; or null
* if the entries' values natural ordering should be used
* @param fInit initialize the index if true
* @param ctx the {@link BackingMapContext context} associated with
* the indexed cache
*/
protected SimpleMapIndex(ValueExtractor extractor, boolean fOrdered,
Comparator comparator, boolean fInit,
BackingMapContext ctx)
{
azzert(extractor != null);
m_extractor = extractor;
m_fOrdered = fOrdered;
m_comparator = comparator;
m_fSplitCollection = !(extractor instanceof MultiExtractor);
m_ctx = ctx;
m_cUnits = 0;
m_calculator = instantiateCalculator();
m_fImmutableValues = extractor instanceof KeyExtractor ||
extractor instanceof AbstractExtractor &&
((AbstractExtractor) extractor).getTarget() == AbstractExtractor.KEY;
if (fInit)
{
initialize(true);
}
}
// ----- MapIndex interface ---------------------------------------------
/**
* {@inheritDoc}
*/
public ValueExtractor getValueExtractor()
{
return m_extractor;
}
/**
* {@inheritDoc}
*/
public boolean isOrdered()
{
return m_fOrdered;
}
/**
* {@inheritDoc}
*/
public boolean isPartial()
{
// an index is partial if there are (corrupted) entries
// which are in the cache but not in the index
return !m_setKeyExcluded.isEmpty();
}
/**
* {@inheritDoc}
*/
public Comparator getComparator()
{
return m_comparator;
}
/**
* {@inheritDoc}
*/
public Map getIndexContents()
{
return m_mapInverse;
}
/**
* {@inheritDoc}
*/
public Object get(Object oKey)
{
Map map = m_mapForward;
if (map == null)
{
return NO_VALUE;
}
Object oValue = map.get(oKey);
return oValue == null && !map.containsKey(oKey) ? NO_VALUE : oValue;
}
/**
* {@inheritDoc}
*/
public void insert(Map.Entry entry)
{
insertInternal(entry);
}
/**
* {@inheritDoc}
*/
public void update(Map.Entry entry)
{
if (!m_fImmutableValues)
{
updateInternal(entry);
}
}
/**
* {@inheritDoc}
*/
public void delete(Map.Entry entry)
{
deleteInternal(entry);
}
// ----- accessors ------------------------------------------------------
/**
* Specifies whether an attempt will be made to search the forward map
* for an existing reference that is "equal" to the specified mutli-value
* and use it instead (if available) to reduce the index memory footprint.
*
* @return true iff multi-value optimization is allowed
*/
public boolean isOptimizeMV()
{
return m_fOptimizeMV;
}
/**
* For an indexed value that is a multi-value (Collection or array) this flag
* specifies whether an attempt should be made to search the forward map
* for an existing reference that is "equal" to the specified mutli-value
* and use it instead (if available) to reduce the index memory footprint.
*
* Note, that even if this optimization is allowed, the full search could be
* quite expensive and our algorithm will always limit the number of cycles
* it spends on the search.
*
* @param fOptimizeMV the boolean value to set
*/
public void setOptimizeMV(boolean fOptimizeMV)
{
m_fOptimizeMV = fOptimizeMV;
}
/**
* Retrieve the size of this index in units (as defined by the
* {@link #getCalculator() UnitCalculator}).
*
* @return the index size
*/
public long getUnits()
{
return m_cUnits;
}
/**
* Set the size of this index in units (as defined by the
* {@link #getCalculator() UnitCalculator}).
*
* @param cUnits new index size
*/
protected void setUnits(long cUnits)
{
m_cUnits = Math.max(cUnits, 0);
}
/**
* Return the UnitCalculator used to size this index's contents.
*
* @return the unit calculator
*/
public UnitCalculator getCalculator()
{
return m_calculator;
}
/**
* Determine whether or not this SimpleMapIndex supports a forward index.
*
* @return true if this SimpleMapIndex supports a forward index; false
* otherwise
*/
public boolean isForwardIndexSupported()
{
return m_fForwardIndex;
}
// ----- helpers --------------------------------------------------------
/**
* Initialize the index's data structures.
*
* @param fForwardIndex specifies whether or not this index supports a
* forward map
*/
protected void initialize(boolean fForwardIndex)
{
m_fForwardIndex = fForwardIndex;
m_mapInverse = instantiateInverseIndex(m_fOrdered, m_comparator);
m_mapForward = fForwardIndex ? instantiateForwardIndex() : null;
m_setKeyExcluded = new SafeHashSet();
}
/**
* Get the forward index entry associated with the specified key.
*
* @param oKey the key
*
* @return the entry associated with the given key
*/
protected Map.Entry getForwardEntry(Object oKey)
{
return m_mapForward == null ? null : ((SegmentedHashMap) m_mapForward).getEntry(oKey);
}
/**
* Add a new mapping to the forward index map.
*
* @param oKey the key to add to the mapping
* @param oIxValueNew the new value to add to the mapping
*/
protected void addForwardEntry(Object oKey, Object oIxValueNew)
{
Map mapForward = m_mapForward;
if (mapForward != null)
{
mapForward.put(oKey, oIxValueNew);
// add the overhead of creating a new map entry
onMappingAdded();
}
}
/**
* Remove the forward index entry for the specified key.
*
* @param oKey the key to remove the forward index entry for
*/
protected void removeForwardEntry(Object oKey)
{
if (m_mapForward != null)
{
m_mapForward.remove(oKey);
// remove the overhead of a map entry
onMappingRemoved();
}
}
/**
* Extract the "new" value from the specified entry.
*
* @param entry the entry to extract the "new" value from
*
* @return the extracted "new" value, or NO_VALUE if the extraction failed
*/
protected Object extractNewValue(Map.Entry entry)
{
try
{
return InvocableMapHelper.extractFromEntry(m_extractor, entry);
}
catch (RuntimeException e)
{
Logger.warn("An Exception occurred during index update for key " + entry.getKey()
+ ". The entry will be excluded from the index"
+ (m_ctx == null ? "" : " for cache " + m_ctx.getCacheName()) + ".\n" + e + ":\n", e);
return NO_VALUE;
}
}
/**
* Extract the "old" value from the specified entry.
*
* @param entry the entry to extract the "old" value from
*
* @return the extracted "old" value, or NO_VALUE if the extraction failed
*/
protected Object extractOldValue(MapTrigger.Entry entry)
{
try
{
return InvocableMapHelper.extractOriginalFromEntry(m_extractor, entry);
}
catch (RuntimeException e)
{
return NO_VALUE;
}
}
/**
* Return a Collection representation of the specified value, which could be
* a Collection, Object[], scalar, or NO_VALUE.
*
* @param oValue the value
*
* @return a Collection representation of the specified value, or an empty
* Collection if NO_VALUE
*/
protected Collection ensureCollection(Object oValue)
{
if (oValue == NO_VALUE)
{
return Collections.emptySet();
}
else if (oValue instanceof Collection)
{
return (Collection) oValue;
}
else if (oValue instanceof Object[])
{
return new ImmutableArrayList((Object[]) oValue).getSet();
}
else
{
return Collections.singleton(oValue);
}
}
/**
* Instantiate the forward index.
*
* Note: To optimize the memory footprint of the forward index, any
* subclasses of the SimpleMapIndex that override this method must also
* implement the {@link #getForwardEntry(Object)} method accordingly.
*
* @return the forward index
*/
protected Map instantiateForwardIndex()
{
// add the overhead of creating a new map
setUnits(getUnits() + IndexCalculator.MAP_OVERHEAD);
return new SegmentedHashMap();
}
/**
* Instantiate the inverse index.
*
* @param fOrdered true iff the contents of the indexed information
* should be ordered; false otherwise
* @param comparator the Comparator object which imposes an ordering
* on entries in the index map; or null
* if the entries' values natural ordering should be
* used
*
* @return the inverse index
*/
protected Map instantiateInverseIndex(boolean fOrdered, Comparator comparator)
{
// add the overhead of creating a new map
setUnits(getUnits() + IndexCalculator.MAP_OVERHEAD);
if (fOrdered)
{
if (!(comparator instanceof SafeComparator))
{
comparator = new SafeComparator(comparator);
}
return new SafeSortedMap(comparator);
}
return new SegmentedHashMap();
}
/**
* Update this index in response to a insert operation on a cache.
*
* @param entry the entry representing the object being inserted
*/
protected void insertInternal(Map.Entry entry)
{
Object oKey = entry instanceof BinaryEntry ?
((BinaryEntry) entry).getBinaryKey() : entry.getKey();
Object oIxValue = extractNewValue(entry);
synchronized (this)
{
if (oIxValue == NO_VALUE)
{
// COH-6447: exclude corrupted entries from index and keep track of them
updateExcludedKeys(entry, true);
}
else
{
// add a new mapping(s) to the inverse index
oIxValue = addInverseMapping(oIxValue, oKey);
addForwardEntry(oKey, oIxValue);
}
}
}
/**
* Update this index in response to an update operation on a cache.
*
* @param entry the entry representing the object being updated
*/
protected void updateInternal(Map.Entry entry)
{
Object oKey = entry instanceof BinaryEntry ?
((BinaryEntry) entry).getBinaryKey() : entry.getKey();
Object oIxValueNew = extractNewValue(entry);
synchronized (this)
{
Object oIxValueOld;
Map.Entry entryFwd = getForwardEntry(oKey);
if (entryFwd == null)
{
if (entry instanceof MapTrigger.Entry)
{
oIxValueOld = extractOldValue((MapTrigger.Entry) entry);
}
else
{
throw new IllegalStateException("Cannot extract the old value");
}
}
else
{
// replace the key reference with a pre-existing equivalent
oKey = entryFwd.getKey();
oIxValueOld = entryFwd.getValue();
}
// replace the mapping(s) in the inverse index (if necessary);
// the inverse index needs to be updated if either the extracted
// values do not match, or if the partial index did not contain the
// previous entry (COH-10259)
if (!equals(oIxValueOld, oIxValueNew) || (entryFwd == null && isPartial()))
{
// remove the old mapping(s) from the inverse index
if (oIxValueOld == NO_VALUE)
{
// extraction of old value failed; must do a full-scan, ensuring that
// any mappings to collection element values in the "new" value will remain
// (COH-7206)
removeInverseMapping(NO_VALUE, oKey, ensureCollection(oIxValueNew));
}
else if (m_fSplitCollection && oIxValueOld instanceof Collection ||
oIxValueOld instanceof Object[])
{
// Note: it's important to only remove the elements that are no longer
// present in the new value (see COH-7206)
removeInverseMapping(collectRemoved(oIxValueOld, oIxValueNew), oKey);
}
else
{
removeInverseMapping(oIxValueOld, oKey);
}
if (oIxValueNew == NO_VALUE)
{
// COH-6447: exclude corrupted entries from index and keep track of them
if (entryFwd != null)
{
removeForwardEntry(oKey);
}
updateExcludedKeys(entry, true);
}
else
{
// add a new mapping(s) to the inverse index
oIxValueNew = addInverseMapping(oIxValueNew, oKey);
// replace the mapping in the forward index
if (entryFwd == null)
{
addForwardEntry(oKey, oIxValueNew);
}
else
{
entryFwd.setValue(oIxValueNew);
}
// entry was successfully updated, ensure that the key is not excluded
updateExcludedKeys(entry, false);
}
}
}
}
/**
* Update this index in response to a remove operation on a cache.
*
* @param entry the entry representing the object being removed
*/
protected void deleteInternal(Map.Entry entry)
{
Object oKey = entry instanceof BinaryEntry ?
((BinaryEntry) entry).getBinaryKey() : entry.getKey();
synchronized (this)
{
Object oIxValueOld;
Map mapForward = m_mapForward;
if (mapForward == null)
{
if (entry instanceof MapTrigger.Entry)
{
oIxValueOld = extractOldValue((MapTrigger.Entry) entry);
}
else
{
throw new IllegalStateException("Cannot extract the old value");
}
}
else
{
// remove the mapping from the forward index
oIxValueOld = mapForward.remove(oKey);
// remove the overhead of deleting a map entry
onMappingRemoved();
}
// remove the mapping(s) from the inverse index
removeInverseMapping(oIxValueOld, oKey);
// make sure the entry is no longer tracked as excluded
updateExcludedKeys(entry, false);
}
}
/**
* Add a new mapping from the given indexed value to the given key in the
* inverse index.
*
* @param oIxValue the indexed value (serves as a key in the inverse index)
* @param oKey the key to insert into the inverse index
*
* @return an already existing reference that is "equal" to the specified
* value (if available)
*/
protected Object addInverseMapping(Object oIxValue, Object oKey)
{
Map mapInverse = m_mapInverse;
// add a new mapping(s) to the inverse index
// if the extracted value has been already "known", substitute
// the one we just extracted with a previously extracted one
// to avoid having multiple copies of equivalent values
if (m_fSplitCollection && oIxValue instanceof Collection
|| oIxValue instanceof Object[])
{
oIxValue = addInverseCollectionMapping(mapInverse, oIxValue, oKey);
}
else
{
oIxValue = addInverseMapping(mapInverse, oIxValue, oKey);
}
return oIxValue;
}
/**
* Add a new mapping from the given indexed value to the given key in the
* supplied index.
*
* @param mapIndex the index to which to add the mapping
* @param oIxValue the indexed value (serves as a key in the inverse index)
* @param oKey the key to insert into the inverse index
*
* @return an already existing reference that is "equal" to the specified
* value (if available)
*/
protected Object addInverseMapping(Map mapIndex, Object oIxValue, Object oKey)
{
Map.Entry entry = m_fOrdered ?
((SafeSortedMap) mapIndex).getEntry(oIxValue) :
((SegmentedHashMap) mapIndex).getEntry(oIxValue);
Object oExtracted = null;
Set setKeys;
if (entry == null)
{
oExtracted = oIxValue;
setKeys = instantiateSet();
mapIndex.put(oExtracted, setKeys);
}
else
{
setKeys = (Set) entry.getValue();
oIxValue = entry.getKey();
}
setKeys.add(oKey);
onMappingAdded(oExtracted, setKeys.size());
return oIxValue;
}
/**
* Add new mappings from the elements of the given value to the given key
* in the supplied index. The given value is expected to be either a
* Collection or an Object array.
*
* @param mapIndex the index to which to add the mapping
* @param oIxValue the indexed Collection value (each element serves
* as a key in the inverse index)
* @param oKey the key to insert into the inverse index
*
* @return an already existing reference that is "equal" to the specified
* value (if available)
*/
protected Object addInverseCollectionMapping(Map mapIndex, Object oIxValue,
Object oKey)
{
// in addition to adding the reverse index we want to find any entry
// in the forward index that is equal to the currently extracted
// collection (oIxValue); naturally that match, if exists, could only
// be a forward index value for some of the keys that "match" all the
// values in the passed in collection
// search for an existing value in forward map for memory optimization
Set setCandidateKeys = null;
boolean fCandidate = m_fOptimizeMV && m_mapForward != null;
boolean fScanForward = false; // search by scanning the forward index
int cCost = 0; // cost factor for retainAll and new LiteSet operation
final int THRESHOLD = 500; // hard-coded threshold to scan forward map
Iterator iterator = oIxValue instanceof Object[] ?
new SimpleEnumerator((Object[]) oIxValue) :
((Collection) oIxValue).iterator();
while (iterator.hasNext())
{
Object oValue = iterator.next();
Object oExtracted = null;
Set setKeys = (Set) mapIndex.get(oValue);
if (setKeys == null)
{
fCandidate = false;
setKeys = instantiateSet();
oExtracted = oValue;
mapIndex.put(oExtracted, setKeys);
}
else if (fCandidate && !fScanForward)
{
if (setCandidateKeys == null)
{
cCost = setKeys.size();
if (cCost <= THRESHOLD)
{
setCandidateKeys = new LiteSet(setKeys);
}
else
{
// for values that are associated with a large number of
// keys, the new LiteSet and retainAll operations are expensive;
// do a controlled scan through the forward index instead
fScanForward = true;
}
}
else
{
// use an empirical cost estimate
cCost += 4 * Math.max(setCandidateKeys.size(), setKeys.size());
if (cCost <= THRESHOLD)
{
setCandidateKeys.retainAll(setKeys);
}
}
}
setKeys.add(oKey);
onMappingAdded(oExtracted, setKeys.size());
}
if (fCandidate && (fScanForward || setCandidateKeys != null))
{
// find an existing reference in the forward index that is "equal"
// to the given (collection or array) value
// if we are scanning the forward index, the iterator holds the values
// to check, otherwise it holds the keys whose values are checked
int cSize = oIxValue instanceof Object[] ?
((Object[]) oIxValue).length :
((Collection) oIxValue).size();
Iterator iter = fScanForward
? m_mapForward.values().iterator()
: setCandidateKeys.iterator();
for (int i = 0, c = 4 * THRESHOLD/(cSize+1); i < c && iter.hasNext(); i++)
{
Object oCandidateValue = fScanForward ? iter.next() : get(iter.next());
if (Base.equalsDeep(oCandidateValue, oIxValue))
{
// found an "equal" reference
return oCandidateValue;
}
}
}
// no match is found; the passed in value should be used for the
// forward map
return oIxValue;
}
/**
* Remove the mapping from the given indexed value to the given key from
* the inverse index.
*
* @param oIxValue the indexed value, or NO_VALUE if unknown
* @param oKey the key
* @param colIgnore the Collection of values to ignore (exclude from removal), or null
*/
protected void removeInverseMapping(Object oIxValue, Object oKey, Collection colIgnore)
{
Map mapInverse = m_mapInverse;
if (oIxValue == NO_VALUE && !isKeyExcluded(oKey))
{
// the old value could not be obtained; must resort to a full-scan
for (Iterator iter = mapInverse.keySet().iterator(); iter.hasNext(); )
{
removeInverseMapping(iter.next(), oKey, colIgnore);
}
}
else if (oIxValue instanceof Collection && m_fSplitCollection)
{
for (Iterator iter = ((Collection) oIxValue).iterator();
iter.hasNext();)
{
Object oElemValue = iter.next();
if (colIgnore == null || !colIgnore.contains(oElemValue))
{
removeInverseMapping(mapInverse, oElemValue, oKey);
}
}
}
else if (oIxValue instanceof Object[])
{
Object[] aoIxValueOld = (Object[]) oIxValue;
for (int i = 0, c = aoIxValueOld.length; i < c; ++i)
{
Object oElemValue = aoIxValueOld[i];
if (colIgnore == null || !colIgnore.contains(oElemValue))
{
removeInverseMapping(mapInverse, oElemValue, oKey);
}
}
}
else
{
removeInverseMapping(mapInverse, oIxValue, oKey);
}
}
/**
* Remove the mapping from the given indexed value to the given key from
* the inverse index.
*
* @param oIxValue the indexed value, or NO_VALUE if unknown
* @param oKey the key
*/
protected void removeInverseMapping(Object oIxValue, Object oKey)
{
removeInverseMapping(oIxValue, oKey, null);
}
/**
* Remove the mapping from the given indexed value to the given key from
* the supplied index.
*
* @param mapIndex the index from which to remove the mapping
* @param oIxValue the indexed value
* @param oKey the key
*/
protected void removeInverseMapping(Map mapIndex, Object oIxValue, Object oKey)
{
Set setKeys = (Set) mapIndex.get(oIxValue);
if (setKeys == null)
{
// there is a legitimate scenario when the inverse index may miss an entry -
// if the entry was evicted during the "build index" phase, in which case oIxValue would be null;
// while there is a possibility that a "null" value is extracted from an existing entry,
// we will ignore that possibility for the [debug] message below
if (!isPartial() && oIxValue != null)
{
logMissingIdx(oIxValue, oKey);
}
}
else
{
Object oExtracted = null;
setKeys.remove(oKey);
if (setKeys.isEmpty())
{
oExtracted = oIxValue;
mapIndex.remove(oExtracted);
}
onMappingRemoved(oExtracted);
}
}
/**
* Log messages for missing inverse index.
*
* @param oIxValue the indexed value
* @param oKey the key
*/
protected void logMissingIdx(Object oIxValue, Object oKey)
{
// COH-5939: limit logging frequency to 10 messages for every 5 minutes interval
long ldtNow = getSafeTimeMillis();
long ldtLogResume = m_ldtLogMissingIdx + 300000L;
if (ldtNow > ldtLogResume)
{
m_ldtLogMissingIdx = ldtNow;
m_cLogMissingIdx = 0;
}
int cLog = ++m_cLogMissingIdx;
if (cLog < 10)
{
log("Missing inverse index: value=" + oIxValue + ", key=" + oKey);
}
else if (cLog == 10)
{
log("Suppressing missing inverse index messages for " +
(ldtLogResume - ldtNow) / 1000 + " seconds");
}
}
/**
* Given that the old value is known to be a Collection or an array,
* collect all the enclosed elements that are not part of the new value.
*
* @param oIxValueOld the old value (must be a collection or an array)
* @param oIxValueNew the new value
*
* @return the set of values that are contained in the old collection or array,
* but not part of the new value
*/
protected Set collectRemoved(Object oIxValueOld, Object oIxValueNew)
{
Set setRemove;
if (oIxValueOld instanceof Collection)
{
// clone the original collection
setRemove = new HashSet((Collection) oIxValueOld);
}
else // oIxValueOld instanceof Object[]
{
setRemove = new HashSet(Arrays.asList((Object[]) oIxValueOld));
}
setRemove.removeAll(ensureCollection(oIxValueNew));
return setRemove;
}
/**
* Factory method used to create a new set containing the keys associated
* with a single value.
*
* @return a Set to keep the corresponding keys at
*/
protected Set instantiateSet()
{
return new InflatableSet();
}
/**
* Factory method used to create a new calculator.
*
* @return a {@link UnitCalculator}
*/
protected UnitCalculator instantiateCalculator()
{
return new IndexCalculator(m_ctx, this);
}
/**
* Decrease the size of the index by the size of an index map entry.
*/
protected void onMappingRemoved()
{
onMappingRemoved(null);
}
/**
* Decrease the size of the index by the estimated size of the specified
* removed value.
*
* @param oValue the value being removed from the index
*/
protected void onMappingRemoved(Object oValue)
{
IndexCalculator calc = (IndexCalculator) getCalculator();
int cb = calc.getEntrySize() +
(oValue == null
? 0
: calc.calculateUnits(null, oValue) +
IndexCalculator.SET_OVERHEAD + IndexCalculator.INFLATION_OVERHEAD);
setUnits(getUnits() - cb);
}
/**
* Increase the size of the index by the size of an index map entry.
*/
protected void onMappingAdded()
{
onMappingAdded(null, 0);
}
/**
* Increase the size of the index by the estimated size of the specified
* added value.
*
* @param oValue the value being added to the index
* @param cSize the current key set size indexed by the given value
*/
protected void onMappingAdded(Object oValue, int cSize)
{
IndexCalculator calc = (IndexCalculator) getCalculator();
int cb = calc.getEntrySize() +
(oValue == null ? 0 : calc.calculateUnits(null, oValue) + IndexCalculator.SET_OVERHEAD) +
(cSize == 2 ? IndexCalculator.INFLATION_OVERHEAD : 0);
setUnits(getUnits() + cb);
}
/**
* Check the entry against the set of entries not included in the index and
* update the set if necessary.
*
* @param entry the entry to be checked
* @param fExclude true iff the insert or update of the entry into the index
* caused an exception
*/
protected void updateExcludedKeys(Map.Entry entry, boolean fExclude)
{
Set setExcluded = m_setKeyExcluded;
if (fExclude || !setExcluded.isEmpty())
{
Object oKey = entry.getKey();
if (fExclude)
{
setExcluded.add(oKey);
}
else
{
setExcluded.remove(oKey);
}
}
}
/**
* Check if the entry with the given key is excluded from the index.
*
* @param oKey the key to test
* @return true if the key is in the list of keys currently excluded
* from the index, false if the entry with the key is in the index
*/
protected boolean isKeyExcluded(Object oKey)
{
return m_setKeyExcluded.contains(oKey);
}
// ----- Object interface -----------------------------------------------
/**
* Returns a string representation of this SimpleMapIndex.
*
* @return a String representation of this SimpleMapIndex
*/
public String toString()
{
return toString(false);
}
/**
* Returns a string representation of this SimpleMapIndex. If called in
* verbose mode, include the contents of the index (the inverse
* index). Otherwise, just print the number of entries in the index.
*
* @param fVerbose if true then print the content of the index otherwise
* print the number of entries
*
* @return a String representation of this SimpleMapIndex
*/
public String toString(boolean fVerbose)
{
return ClassHelper.getSimpleName(getClass())
+ ": Extractor=" + getValueExtractor()
+ ", Ordered=" + isOrdered()
+ ", Footprint="+ Base.toMemorySizeString(getUnits(), false)
+ ", Content="
+ (fVerbose ? getIndexContents().keySet() : getIndexContents().size());
}
/**
* Compares the specified object with this index for equality. Returns
* true if the given object is also a SimpleMapIndex and the two
* represent the same index.
*
* @param o object to be compared for equality with this MapIndex
*
* @return true if the specified object is equal to this index
*/
public boolean equals(Object o)
{
if (this == o)
{
return true;
}
if (!(o instanceof SimpleMapIndex))
{
return false;
}
SimpleMapIndex that = (SimpleMapIndex) o;
return equals(this.getComparator(), that.getComparator()) &&
equals(this.getValueExtractor(), that.getValueExtractor()) &&
this.isOrdered() == that.isOrdered();
}
/**
* Returns the hash code value for this MapIndex.
*
* @return the hash code value for this MapIndex
*/
public int hashCode()
{
return m_comparator == null ? 0 : m_comparator.hashCode() +
m_extractor.hashCode() + (m_fOrdered ? 1 : 0);
}
// ----- inner class: IndexCalculator -----------------------------------
/**
* A stateful {@link
* com.tangosol.net.cache.ConfigurableCacheMap.UnitCalculator calculator}
* used to calculate the cost of a homogeneous index (holding all values of a
* single type).
*/
public static class IndexCalculator
extends SimpleMemoryCalculator
{
// ----- constructors -----------------------------------------------
/**
* Construct an IndexCalculator which allows for conversion of items into
* a serialized format. The calculator may use the size of the serialized
* value representation to approximate the size of indexed values.
*
* Note: {@link ExternalizableHelper#CONVERTER_TO_BINARY} can be used to
* convert Serializable or ExternalizableLite objects
*
* @param ctx the {@link BackingMapContext} associated with the indexed cache
* @param index the container index for this calculator (used only for logging)
*/
public IndexCalculator(BackingMapContext ctx, SimpleMapIndex index)
{
m_index = index;
if (ctx == null)
{
m_converter = null;
m_calculator = null;
return;
}
m_converter = ctx.getManagerContext().getValueToInternalConverter();
Map mapBack = ctx.getBackingMap();
if (mapBack instanceof ReadWriteBackingMap)
{
mapBack = ((ReadWriteBackingMap) mapBack).getInternalCache();
}
if (mapBack instanceof ConfigurableCacheMap)
{
m_calculator = ((ConfigurableCacheMap) mapBack).getUnitCalculator();
}
else
{
m_calculator = null;
}
}
// ----- IndexCalculator methods ------------------------------------
/**
* Determine which method to use to count the size of an instance of the
* specified class.
*
* @param clz the type of objects that this calculator will operate on
*
* @return the {@link CalculatorState}
*/
protected CalculatorState getCalculatorState(Class clz)
{
if (MAP_FIXED_SIZES.containsKey(clz))
{
return CalculatorState.FIXED;
}
if (clz == String.class || clz == Binary.class)
{
return CalculatorState.STANDARD;
}
if (clz.isArray())
{
// check if the component type is either FIXED or STANDARD.
// If so, the standard calculator can count the size
switch (getCalculatorState(clz.getComponentType()))
{
case FIXED:
case STANDARD:
return CalculatorState.STANDARD;
default:
break;
}
}
// the calculator cannot calculate the size
return CalculatorState.UNKNOWN;
}
/**
* Initialize the calculator based on the type of the specified object
* assuming that the indexed values are homogeneous (of the same type).
*
* @param o an instance of the value to calculate the size for
*
* @return the new {@link CalculatorState}
*/
protected synchronized CalculatorState initialize(Object o)
{
// Note: this method is synchronized to protect the against possible
// concurrent initialization on multiple threads
UnitCalculator calculator = m_calculator;
if (calculator != null)
{
try
{
calculator.calculateUnits(null, o);
return m_state = CalculatorState.CONFIGURED;
}
catch (IllegalArgumentException e)
{
// the cache calculator does not work for the index
// (most likely it's just a BinaryCalculator)
}
}
CalculatorState state = m_state;
if (state == CalculatorState.UNINITIALIZED)
{
state = getCalculatorState(o.getClass());
switch (state)
{
case UNKNOWN:
{
String sMsg;
if (calculator == null)
{
sMsg = "There is no configured calculator "
+ "for " + o.getClass().getCanonicalName()
+ "; this " + m_index + " will"
+ " estimate the index size using serialization,"
+ " which could impact its performance";
}
else
{
sMsg = "The configured calculator "
+ calculator.getClass().getCanonicalName()
+ " cannot be used to estimate the size of "
+ o.getClass().getCanonicalName()
+ "; this " + m_index + " will"
+ " estimate the index size using serialization,"
+ " which could impact its performance";
}
Logger.info(sMsg);
m_state = state;
break;
}
case FIXED:
m_cbFixed = super.sizeOf(o);
// fall-through
default:
m_state = state;
break;
}
}
return state;
}
// ----- SimpleMemoryCalculator methods -----------------------------
/**
* {@inheritDoc}
*/
protected int getEntrySize()
{
return ENTRY_OVERHEAD;
}
/**
* {@inheritDoc}
*/
public int sizeOf(Object o)
{
try
{
switch (m_state)
{
case UNINITIALIZED:
initialize(o);
return sizeOf(o);
case FIXED:
return m_cbFixed;
case STANDARD:
return super.sizeOf(o);
case CONFIGURED:
return m_calculator.calculateUnits(null, o);
case UNKNOWN:
Converter conv = getConverter();
return conv == null
? DEFAULT_SIZE
: super.sizeOf(conv.convert(o));
default:
throw new IllegalStateException();
}
}
catch (Exception e)
{
// something went wrong with either conversion or the index
// the index was thought to be STANDARD, but appears to be not
// homogeneous
return DEFAULT_SIZE;
}
}
/**
* Return the converter used by this IndexCalculator, or null.
*
* @return the converter used by this IndexCalculator
*/
protected Converter getConverter()
{
return m_converter;
}
// ----- enum: CalculatorState --------------------------------------
/**
* The CalculatorState identifies the method used by the calculator to
* calculate the cost of a key or a value type. There are four states:
*
* - UNINITIALIZED - The calculator has not yet been initialized;
*
- UNKNOWN - The calculator is unable to determine the exact size for
* this type. It will either use a pluggable calculator or an
* approximation based on the serialized size. The {@link
* IndexCalculator#DEFAULT_SIZE} will be used as a fallback;
*
- FIXED - instances of the key or value will always be of the same
* size (e.g. int, short, double).
*
- STANDARD - instances of the key or value type need to be
* calculated by the unit calculator (e.g. Binary, String).
*
- CONFIGURED - The configured calculator on the cache where the
* index is defined will be used to calculate the size.
*
*/
public static enum CalculatorState
{
UNINITIALIZED, UNKNOWN, FIXED, STANDARD, CONFIGURED
}
// ----- data members and constants ---------------------------------
/**
* The container index. Since we use an enum for the state we have to
* make this inner class a static one and pass the parent index into
* the constructor.
*/
protected SimpleMapIndex m_index;
/**
* The {@link CalculatorState} of this calculator.
*/
protected CalculatorState m_state = CalculatorState.UNINITIALIZED;
/**
* If the state is {@link CalculatorState#FIXED}, contains a cached cost
* per instance.
*/
protected int m_cbFixed;
/**
* The {@link Converter} used to convert {@link CalculatorState#UNKNOWN}
* types into {@link Binary} to approximate the size.
*/
protected final Converter m_converter;
/**
* The {@link UnitCalculator} used to calculate the size of {@link CalculatorState#CONFIGURED}
* types. into {@link Binary} to approximate the size.
* The calculator is initialized iff the {@link BackingMapContext} associated
* with the index represents a {@link ConfigurableCacheMap}
*/
protected final UnitCalculator m_calculator;
/**
* The memory cost of a SegmentedHashMap used as the Forward Index.
*/
protected static final int MAP_OVERHEAD = calculateShallowSize(SegmentedHashMap.class) +
padMemorySize(SIZE_BASIC_OBJECT + 4);
/**
* The average memory cost of creating SegmentedHashMap$Entry or SafeHashMap$Entry.
*/
protected static final int ENTRY_OVERHEAD = padMemorySize(SIZE_OBJECT_REF + 4) +
(calculateShallowSize(SegmentedHashMap.Entry.class) +
calculateShallowSize(SafeHashMap.Entry.class)) / 2;
/**
* The memory cost of creating an InflatableSet.
*
* This cost does not include post inflation of the set; INFLATION_OVERHEAD
* should be considered as a one-off memory cost to be added post inflation.
*/
protected static final int SET_OVERHEAD = calculateShallowSize(InflatableSet.class);
/**
* The memory cost of inflating an InflatableSet. The inflation can be determined
* when its size grows from 1 to 2, at which point INFLATION_OVERHEAD should
* be added to any models predicting memory usage.
*/
protected static final int INFLATION_OVERHEAD = calculateShallowSize(SafeHashMap.class) +
calculateShallowSize(InflatableSet.class) + SIZE_OBJECT +
padMemorySize(SIZE_BASIC_OBJECT + 4);
/**
* The default size of an entry used if the calculator is unable to
* calculate the size.
*/
protected static final int DEFAULT_SIZE = 32;
}
// ----- data members ---------------------------------------------------
/**
* ValueExtractor object that this MapIndex uses to extract an indexable
* property value from a [converted] value stored in the resource map.
*/
protected ValueExtractor m_extractor;
/**
* Comparator used to sort the index. Used iff the Ordered flag is true.
* Null implies a natural order.
*/
protected Comparator m_comparator;
/**
* Specifies whether or not this MapIndex orders the contents of the
* indexed information.
*/
protected boolean m_fOrdered;
/**
* Map that contains the index values (forward index). The keys of the Map
* are the keys to the map being indexed and the values are the extracted
* values. This map is used by the IndexAwareComparators to avoid a
* conversion and value extraction steps.
*/
protected Map m_mapForward;
/**
* For an indexed value that is a multi-value (Collection or array) this flag
* specifies whether an attempt should be made to search the forward map
* for an existing reference that is "equal" to the specified mutli-value
* and use it instead (if available) to reduce the index memory footprint.
*
* Note, that even if this optimization is allowed, the full search could be
* quite expensive and our algorithm will always limit the number of cycles
* it spends on the search.
*/
private boolean m_fOptimizeMV = true;
/**
* Map that contains the index contents (inverse index). The keys of the
* Map are the return values from the ValueExtractor operating against the
* entries of the resource map, and for each key, the corresponding value
* stored in the Map is a Set of keys to the resource map.
*/
protected Map m_mapInverse;
/**
* If a value extracted by the ValueExtractor is a Collection, this
* property specifies whether or not it should be treated as a Collection
* of contained attributes or indexed as a single composite attribute.
*/
protected boolean m_fSplitCollection;
/**
* The size footprint of the index, in units (as defined by the UnitCalculator).
*/
protected volatile long m_cUnits;
/**
* UnitCalculator used to estimate the cost of a value.
*/
protected UnitCalculator m_calculator;
/**
* The {@link BackingMapContext context} associated with this index.
*/
protected BackingMapContext m_ctx;
/**
* The time at which the most recent logging of "missing inverse index"
* messages started.
*/
protected long m_ldtLogMissingIdx;
/**
* The number of "missing inverse index" messages that have been logged.
*/
protected int m_cLogMissingIdx;
/**
* A set of keys for the entries, which could not be included in the index.
*/
protected Set m_setKeyExcluded;
/**
* Specifies whether or not this MapIndex supports a forward index.
*/
protected boolean m_fForwardIndex;
/**
* Specifies whether or not the index is based on the immutable values (e.g. keys).
*/
protected boolean m_fImmutableValues;
}