com.l2jfree.gameserver.idfactory.BitSetIDFactory.java Source code

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Here is the source code for com.l2jfree.gameserver.idfactory.BitSetIDFactory.java

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/*
 * This program is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later
 * version.
 * 
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 * details.
 * 
 * You should have received a copy of the GNU General Public License along with
 * this program. If not, see <http://www.gnu.org/licenses/>.
 */
package com.l2jfree.gameserver.idfactory;

import java.util.BitSet;
import java.util.concurrent.atomic.AtomicInteger;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.l2jfree.gameserver.ThreadPoolManager;
import com.l2jfree.tools.util.PrimeFinder;

/**
 * This class ...
 * 
 * @author luisantonioa
 * @version $Revision: 1.2 $ $Date: 2004/06/27 08:12:59 $
 */

public class BitSetIDFactory extends IdFactory {
    private final static Log _log = LogFactory.getLog(BitSetIDFactory.class);

    private BitSet _freeIds;
    private AtomicInteger _freeIdCount;
    private AtomicInteger _nextFreeId;

    protected class BitSetCapacityCheck implements Runnable {
        @Override
        public void run() {
            synchronized (BitSetIDFactory.this) {
                if (reachingBitSetCapacity())
                    increaseBitSetCapacity();
            }
        }

    }

    protected BitSetIDFactory() {
        super();

        synchronized (BitSetIDFactory.class) {
            ThreadPoolManager.getInstance().scheduleGeneralAtFixedRate(new BitSetCapacityCheck(), 30000, 30000);
            initialize();
        }
        _log.info("IDFactory: " + _freeIds.size() + " id's available.");
    }

    public void initialize() {
        try {
            _freeIds = new BitSet(PrimeFinder.nextPrime(100000));
            _freeIds.clear();
            _freeIdCount = new AtomicInteger(FREE_OBJECT_ID_SIZE);

            for (int usedObjectId : extractUsedObjectIDTable()) {
                int objectID = usedObjectId - FIRST_OID;
                if (objectID < 0) {
                    // auction hack
                    if (usedObjectId == 100100) {
                        continue;
                    }

                    _log.warn("Object ID " + usedObjectId + " in DB is less than minimum ID of " + FIRST_OID);
                    continue;
                }
                _freeIds.set(usedObjectId - FIRST_OID);
                _freeIdCount.decrementAndGet();
            }

            _nextFreeId = new AtomicInteger(_freeIds.nextClearBit(0));
            _initialized = true;
        } catch (Exception e) {
            _initialized = false;
            _log.fatal("BitSet ID Factory could not be initialized correctly", e);
        }
    }

    @Override
    public synchronized void releaseId(int objectID) {
        if ((objectID - FIRST_OID) > -1) {
            _freeIds.clear(objectID - FIRST_OID);
            _freeIdCount.incrementAndGet();
        } else
            _log.warn("BitSet ID Factory: release objectID " + objectID + " failed (< " + FIRST_OID + ")");
    }

    @Override
    public synchronized int getNextId() {
        int newID = _nextFreeId.get();
        _freeIds.set(newID);
        _freeIdCount.decrementAndGet();

        int nextFree = _freeIds.nextClearBit(newID);

        if (nextFree < 0) {
            nextFree = _freeIds.nextClearBit(0);
        }
        if (nextFree < 0) {
            if (_freeIds.size() < FREE_OBJECT_ID_SIZE) {
                increaseBitSetCapacity();
            } else {
                throw new IndexOutOfBoundsException("Ran out of valid Id's.");
            }
        }

        _nextFreeId.set(nextFree);

        return newID + FIRST_OID;
    }

    @Override
    public synchronized int size() {
        return _freeIdCount.get();
    }

    protected synchronized int usedIdCount() {
        return (size() - FIRST_OID);
    }

    protected synchronized boolean reachingBitSetCapacity() {
        return PrimeFinder.nextPrime(usedIdCount() * 11 / 10) > _freeIds.size();
    }

    protected synchronized void increaseBitSetCapacity() {
        BitSet newBitSet = new BitSet(PrimeFinder.nextPrime(usedIdCount() * 11 / 10));
        newBitSet.or(_freeIds);
        _freeIds = newBitSet;
    }

    @Override
    public int getCurrentId() {
        return 0;
    }
}