/*
* Copyright (c) 2001-2007 Sun Microsystems, Inc. All rights reserved.
*
* The Sun Project JXTA(TM) Software License
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. The end-user documentation included with the redistribution, if any, must
* include the following acknowledgment: "This product includes software
* developed by Sun Microsystems, Inc. for JXTA(TM) technology."
* Alternately, this acknowledgment may appear in the software itself, if
* and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must
* not be used to endorse or promote products derived from this software
* without prior written permission. For written permission, please contact
* Project JXTA at http://www.jxta.org.
*
* 5. Products derived from this software may not be called "JXTA", nor may
* "JXTA" appear in their name, without prior written permission of Sun.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SUN
* MICROSYSTEMS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* JXTA is a registered trademark of Sun Microsystems, Inc. in the United
* States and other countries.
*
* Please see the license information page at :
* <http://www.jxta.org/project/www/license.html> for instructions on use of
* the license in source files.
*
* ====================================================================
*
* This software consists of voluntary contributions made by many individuals
* on behalf of Project JXTA. For more information on Project JXTA, please see
* http://www.jxta.org.
*
* This license is based on the BSD license adopted by the Apache Foundation.
*/
package net.jxta.impl.cm.srdi.inmemory;
import net.jxta.impl.util.TimeUtils;
import net.jxta.logging.Logging;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.logging.Level;
import java.util.logging.Logger;
// The GC Index: this index organises the Entries by expiration time and is used for Garbage Collection
public class GcIndex {
private final static transient Logger LOG = Logger.getLogger( GcIndex.class.getName( ) );
private Map<Long, Set<GcKey>> gcIndex = Collections.synchronizedMap( new TreeMap<Long, Set<GcKey>>( ) );
private final String indexName;
public GcIndex( final String indexName ) {
this.indexName = indexName;
}
public void clear( ) {
this.gcIndex.clear( );
}
/**
* DEBUG only as it's VERY expensive to run
* @return A String containing printable statistics about this Index
*/
public String getStats( ) {
int registrations = 0;
Set<Long> expList = this.gcIndex.keySet( );
Collection<Set<GcKey>> sets = this.gcIndex.values( );
for ( Set<GcKey> set : sets ) {
registrations += set.size( );
}
long now = TimeUtils.timeNow( );
long hour = now + TimeUtils.ANHOUR;
long day = now + TimeUtils.ADAY;
long week = now + TimeUtils.AWEEK;
long month = now + ( TimeUtils.AWEEK * 4 );
long year = now + TimeUtils.AYEAR;
int negative = 0;
int greaterThanOrEqualToZeroAndLessThanAnHour = 0;
int greaterThanOrEqualToAnHourAndLessThanADay = 0;
int greaterThanOrEqualToADayAndLessThanAWeek = 0;
int greaterThatOrEqualToAWeekAndLessThanAMonth = 0;
int greaterThanOrEqualToAMonthAndLessThanAYear = 0;
int greaterThanOrEqualToAYear = 0;
for ( Long exp : expList ) {
if ( exp >= year ) {
greaterThanOrEqualToAYear++;
} else {
if ( exp >= month ) {
greaterThanOrEqualToAMonthAndLessThanAYear++;
} else {
if ( exp >= week ) {
greaterThatOrEqualToAWeekAndLessThanAMonth++;
} else {
if ( exp >= day ) {
greaterThanOrEqualToADayAndLessThanAWeek++;
} else {
if ( exp >= hour ) {
greaterThanOrEqualToAnHourAndLessThanADay++;
} else {
if ( exp >= 0 ) {
greaterThanOrEqualToZeroAndLessThanAnHour++;
} else {
negative++;
}
}
}
}
}
}
}
return "GcIndex [" + this.indexName + "]: " + expList.size( ) + " expiry times\t" + registrations + " map elements.\n" +
" <0: " + negative + ", <hour: " + greaterThanOrEqualToZeroAndLessThanAnHour + ", <day: " +
greaterThanOrEqualToAnHourAndLessThanADay + ", <week: " + greaterThanOrEqualToADayAndLessThanAWeek +
", <month: " + greaterThatOrEqualToAWeekAndLessThanAMonth + ", <year: " +
greaterThanOrEqualToAMonthAndLessThanAYear + ", >=year: " + greaterThanOrEqualToAYear;
}
public Long[] getAllKeys( ) {
Long[] expirations = null;
Set<Long> expList = this.gcIndex.keySet( );
expirations = expList.toArray( new Long[ expList.size( ) ] );
return expirations;
}
public Set<GcKey> remove( final Long expiry ) {
return this.gcIndex.remove( expiry );
}
public boolean remove( final Long expiry, final GcKey gcKey ) {
Set<GcKey> gcKeys = this.gcIndex.get( expiry );
if ( gcKeys != null ) {
if ( false == gcKeys.remove( gcKey ) ) {
if ( Logging.SHOW_WARNING && LOG.isLoggable( Level.WARNING ) ) {
LOG.log( Level.WARNING,
"[" + this.indexName + "] Remove set value using key: " + gcKey + " when set contains no previous value!" );
}
}
if ( gcKeys.size( ) == 0 ) {
// No more entry to expire... remove entry form the GC Index
if ( Logging.SHOW_DEBUG && LOG.isLoggable( Level.FINE ) ) {
LOG.fine( "[" + this.indexName + "] GC Index: removing entry '" + expiry + "'" );
}
if ( null == remove( expiry ) ) {
if ( Logging.SHOW_WARNING && LOG.isLoggable( Level.WARNING ) ) {
LOG.log( Level.WARNING,
"[" + this.indexName + "] Remove value using key: " + expiry + " when index contains no previous value!" );
}
}
}
}
return true;
}
/**
* Adds an IndexItem to the main GC expiration Index
*
* Items are "removed" by setting their expiration time to -1 and
* updating their entry in this index so that they can be GCed on
* the next Garbage Collector run
*
* @param value The {@link GcKey} to add to the Garbage Collector
* @param expiry The absolute time at which this item will expire
*/
public boolean add( final Long expiry, final GcKey value ) {
Set<GcKey> gcKeys;
gcKeys = this.gcIndex.get( expiry );
if ( null == gcKeys ) {
gcKeys = Collections.synchronizedSet( new HashSet<GcKey>( ) );
this.gcIndex.put( expiry, gcKeys );
}
gcKeys.add( value );
return true;
}
}