Modularizes the Maven project

This commit modularizes the maven project into several modules:
 - l2jserver2-common: common sources for both login and gameserver
 - l2jserver2-gameserver: the game server
 - l2jserver2-loginserver: the login server
 - l2jserver2-tools: refactored src/tools/java soure folder

l2jserver2-common/src/main/java/com/l2jserver/model/AbstractModel.java

@@ -0,0 +1,110 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver 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.
+ *
+ * l2jserver 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 l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.model;
+
+import com.google.common.base.Preconditions;
+import com.l2jserver.model.id.ID;
+
+/**
+ * Simple model interface implementing {@link ID} related methods
+ * 
+ * @param <T>
+ *            the ID type used to represent this {@link Model}
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public abstract class AbstractModel<T extends ID<?>> implements Model<T> {
+	/**
+	 * The object id
+	 */
+	protected T id;
+	/**
+	 * The database object state
+	 */
+	protected transient ObjectDesire desire = ObjectDesire.INSERT;
+
+	@Override
+	public T getID() {
+		return id;
+	}
+
+	@Override
+	public void setID(T ID) {
+		Preconditions.checkState(id == null, "ID is already set");
+		desireInsert();
+		this.id = ID;
+	}
+
+	@Override
+	public ObjectDesire getObjectDesire() {
+		return desire;
+	}
+
+	@Override
+	public void setObjectDesire(ObjectDesire desire) {
+		if (desire == null)
+			desire = ObjectDesire.NONE;
+		this.desire = desire;
+	}
+
+	/**
+	 * Set this object desire to {@link ObjectDesire#UPDATE}. If the desire is
+	 * {@link ObjectDesire#INSERT} or {@link ObjectDesire#DELETE} the desire
+	 * will not be changed.
+	 */
+	@SuppressWarnings("javadoc")
+	protected void desireUpdate() {
+		if (this.desire != ObjectDesire.INSERT
+				&& this.desire != ObjectDesire.DELETE)
+			this.desire = ObjectDesire.UPDATE;
+	}
+
+	/**
+	 * Set this object desire to {@link ObjectDesire#INSERT}. If the desire is
+	 * {@link ObjectDesire#DELETE} the desire will not be changed.
+	 */
+	@SuppressWarnings("javadoc")
+	protected void desireInsert() {
+		if (this.desire != ObjectDesire.DELETE)
+			this.desire = ObjectDesire.INSERT;
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((id == null) ? 0 : id.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		AbstractModel<?> other = (AbstractModel<?>) obj;
+		if (id == null) {
+			if (other.id != null)
+				return false;
+		} else if (!id.equals(other.id))
+			return false;
+		return true;
+	}
+}

l2jserver2-common/src/main/java/com/l2jserver/model/Model.java

@@ -0,0 +1,104 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver 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.
+ *
+ * l2jserver 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 l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.model;
+
+import com.l2jserver.model.id.ID;
+import com.l2jserver.service.database.DatabaseService;
+
+/**
+ * Base model. Each object model must implement this interface to be able to be
+ * inserted into the database.
+ * 
+ * @param <T>
+ *            the {@link ID} type used to represent this {@link Model}
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public interface Model<T extends ID<?>> {
+	/**
+	 * @return the object ID
+	 */
+	T getID();
+
+	/**
+	 * Please note that the ID can only be set one time. Once it has been set,
+	 * it cannot be changed and a {@link IllegalStateException} will be thrown
+	 * if trying to change the ID.
+	 * 
+	 * @param ID
+	 *            the object ID to set
+	 * @throws IllegalStateException
+	 *             if the ID was already set
+	 */
+	void setID(T ID) throws IllegalStateException;
+
+	/**
+	 * Each object has an desire. Desires express what the
+	 * {@link DatabaseService} should do with the object. The service
+	 * automatically keep tracks of every database object (and release them when
+	 * they are garbage collected).
+	 * 
+	 * @return the database object desire
+	 */
+	ObjectDesire getObjectDesire();
+
+	/**
+	 * Each object has an desire. Desires express what the
+	 * {@link DatabaseService} should do with the object. The service
+	 * automatically keep tracks of every database object (and release them when
+	 * they are garbage collected).
+	 * 
+	 * @param desire
+	 *            the database object desire to set
+	 */
+	void setObjectDesire(ObjectDesire desire);
+
+	/**
+	 * Indicated what the object wants to do in the database. It indicates
+	 * whether the object should be inserted, updated or deleted from the
+	 * database.
+	 * 
+	 * @author <a href="http://www.rogiel.com">Rogiel</a>
+	 */
+	public enum ObjectDesire {
+		/**
+		 * Don't do anything
+		 */
+		NONE,
+		/**
+		 * Insert a new object into database.
+		 * <p>
+		 * If the primary key is auto generated by the database a clone of this
+		 * object will be created.<br>
+		 * If the primary key is <b>not</b> auto generated by the database, an
+		 * database exception will occur.
+		 */
+		INSERT,
+		/**
+		 * Updates the object in the database.
+		 * <p>
+		 * If the object is not in the database nothing will happen.
+		 */
+		UPDATE,
+		/**
+		 * Deletes the object from the database.
+		 * <p>
+		 * If tge object is not in the database nothing will happen.
+		 */
+		DELETE;
+	}
+}

l2jserver2-common/src/main/java/com/l2jserver/model/id/AbstractModelID.java

@@ -0,0 +1,47 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver 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.
+ *
+ * l2jserver 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 l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.model.id;
+
+import com.l2jserver.model.Model;
+
+/**
+ * This is an abstract ID for most model objects.
+ * 
+ * @param <T>
+ *            the raw id type
+ * @param <O>
+ *            the model this {@link ID} provides
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public abstract class AbstractModelID<T, O extends Model<? extends ID<T>>>
+		extends ID<T> {
+	/**
+	 * @param id
+	 *            the id
+	 */
+	protected AbstractModelID(T id) {
+		super(id);
+	}
+
+	/**
+	 * @return the {@link Model} object associated with this
+	 *         {@link AbstractModelID}. <tt>null</tt> if {@link Model} does not
+	 *         exists.
+	 */
+	public abstract O getObject();
+}

l2jserver2-common/src/main/java/com/l2jserver/model/id/ID.java

@@ -0,0 +1,81 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver 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.
+ *
+ * l2jserver 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 l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.model.id;
+
+import com.google.inject.Inject;
+
+/**
+ * The ID interface. Each object must be represented by an unique ID.
+ * 
+ * @param <T>
+ *            the raw id type
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public abstract class ID<T> {
+	/**
+	 * The id itself
+	 */
+	protected final T id;
+
+	/**
+	 * @param id
+	 *            the raw id
+	 */
+	@Inject
+	protected ID(T id) {
+		this.id = id;
+	}
+
+	/**
+	 * @return the id
+	 */
+	public T getID() {
+		return id;
+	}
+
+	@Override
+	public String toString() {
+		return this.getClass().getSimpleName() + " [id=" + id + "]";
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + id.hashCode() + this.getClass().hashCode();
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		@SuppressWarnings("rawtypes")
+		ID other = (ID) obj;
+		if (id == null) {
+			if (other.id != null)
+				return false;
+		} else if (!id.equals(other.id))
+			return false;
+		return true;
+	}
+}

l2jserver2-common/src/main/java/com/l2jserver/model/id/compound/AbstractCompoundID.java

@@ -0,0 +1,73 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver 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.
+ *
+ * l2jserver 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 l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.model.id.compound;
+
+import com.l2jserver.model.id.ID;
+
+/**
+ * The compound {@link ID} is composed of two IDs.
+ * 
+ * @param <T1>
+ *            the first {@link ID} type
+ * @param <T2>
+ *            the second {@link ID} type
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public class AbstractCompoundID<T1, T2> extends ID<AbstractCompoundID<T1, T2>> {
+	/**
+	 * The first ID
+	 */
+	private final T1 id1;
+	/**
+	 * The second ID
+	 */
+	private final T2 id2;
+
+	/**
+	 * Creates a new compound ID
+	 * 
+	 * @param id1
+	 *            the first id
+	 * @param id2
+	 *            the second id
+	 */
+	protected AbstractCompoundID(T1 id1, T2 id2) {
+		super(null);
+		this.id1 = id1;
+		this.id2 = id2;
+	}
+
+	/**
+	 * @return the first id
+	 */
+	public T1 getID1() {
+		return id1;
+	}
+
+	/**
+	 * @return the second id
+	 */
+	public T2 getID2() {
+		return id2;
+	}
+
+	@Override
+	public AbstractCompoundID<T1, T2> getID() {
+		return this;
+	}
+}

l2jserver2-common/src/main/java/com/l2jserver/model/id/object/allocator/BitSetIDAllocator.java

@@ -0,0 +1,163 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver 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.
+ *
+ * l2jserver 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 l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.model.id.object.allocator;
+
+import java.util.BitSet;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.l2jserver.util.PrimeFinder;
+
+/**
+ * The {@link BitSet} id allocator allocates new IDs backed by an {@link BitSet}
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public class BitSetIDAllocator implements IDAllocator {
+	/**
+	 * The logger
+	 */
+	private static final Logger log = LoggerFactory
+			.getLogger(BitSetIDAllocator.class);
+
+	/**
+	 * Lock to guarantee synchronization
+	 */
+	private Lock lock = new ReentrantLock();
+
+	/**
+	 * Available IDs
+	 */
+	private BitSet ids = new BitSet();
+	/**
+	 * Amount of free ids
+	 */
+	private AtomicInteger freeIdCount = new AtomicInteger();
+	/**
+	 * Next free ID
+	 */
+	private AtomicInteger nextId = new AtomicInteger();
+
+	/**
+	 * Initializes this allocator
+	 */
+	public void init() {
+		ids = new BitSet(PrimeFinder.nextPrime(100000));
+		ids.clear();
+		freeIdCount = new AtomicInteger(ALLOCABLE_IDS);
+
+		nextId = new AtomicInteger(ids.nextClearBit(0));
+		log.info("BitSet IDAllocator initialized. Next available ID is {}",
+				nextId.get());
+	}
+
+	@Override
+	public void allocate(int id) {
+		if (ids.get(id - FIRST_ID))
+			throw new IDAllocatorException("ID not allocated");
+		log.debug("Allocating ID {}", id);
+		lock.lock();
+		try {
+			if (id < FIRST_ID)
+				return;
+			ids.set(id - FIRST_ID);
+			nextId = new AtomicInteger(ids.nextClearBit(0));
+		} finally {
+			lock.unlock();
+		}
+	}
+
+	@Override
+	public int allocate() {
+		lock.lock();
+		try {
+			final int newID = nextId.get();
+			ids.set(newID);
+			freeIdCount.decrementAndGet();
+
+			if (log.isDebugEnabled())
+				log.debug("Allocated a new ID {}", newID + FIRST_ID);
+
+			int nextFree = ids.nextClearBit(newID);
+
+			if (nextFree < 0) {
+				nextFree = ids.nextClearBit(0);
+			}
+			if (nextFree < 0) {
+				if (ids.size() < ALLOCABLE_IDS) {
+					increaseBitSetCapacity();
+				} else {
+					log.error("ID exhaustion");
+					throw new IDAllocatorException("ID exhaustion");
+				}
+			}
+
+			nextId.set(nextFree);
+			return newID + FIRST_ID;
+		} finally {
+			lock.unlock();
+		}
+	}
+
+	@Override
+	public void release(int id) {
+		if (id < FIRST_ID)
+			throw new IDAllocatorException(
+					"Can't release ID, smaller then initial ID");
+		if (!ids.get(id - FIRST_ID))
+			throw new IDAllocatorException("ID not allocated");
+
+		log.debug("Releasing allocated ID {}", id);
+		lock.lock();
+		try {
+			ids.clear(id - FIRST_ID);
+			freeIdCount.incrementAndGet();
+		} finally {
+			lock.unlock();
+		}
+	}
+
+	@Override
+	public void clear() {
+		ids.clear();
+	}
+
+	/**
+	 * Increases the {@link BitSet} capacity
+	 */
+	private void increaseBitSetCapacity() {
+		log.debug("Increasing BitSet capacity from {}", ids.size());
+		BitSet newBitSet = new BitSet(
+				PrimeFinder.nextPrime((getAllocatedIDs() * 11) / 10));
+		newBitSet.or(ids);
+		ids = newBitSet;
+	}
+
+	@Override
+	public int getAllocatedIDs() {
+		return ALLOCABLE_IDS - getFreeIDs();
+	}
+
+	@Override
+	public int getFreeIDs() {
+		return freeIdCount.get();
+	}
+}

l2jserver2-common/src/main/java/com/l2jserver/model/id/object/allocator/IDAllocator.java

@@ -0,0 +1,80 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver 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.
+ *
+ * l2jserver 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 l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.model.id.object.allocator;
+
+/**
+ * The ID allocator is used to alloc new ID and to release IDs that aren't used
+ * anymore.
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public interface IDAllocator {
+	/**
+	 * The first ID ever allocated
+	 */
+	public final static int FIRST_ID = 0x10000000;
+	/**
+	 * The last ID ever allocated
+	 */
+	public final static int LAST_ID = 0x7FFFFFFF;
+	/**
+	 * Total of available IDs for allocation
+	 */
+	public final static int ALLOCABLE_IDS = LAST_ID - FIRST_ID;
+
+	/**
+	 * This is method is used to register IDs as used at startup time.
+	 * 
+	 * @param id
+	 *            the id
+	 */
+	void allocate(int id);
+
+	/**
+	 * Allocates a new ID
+	 * 
+	 * @return the allocated ID value
+	 */
+	int allocate();
+
+	/**
+	 * Release an ID
+	 * 
+	 * @param id
+	 *            the id
+	 */
+	void release(int id);
+
+	/**
+	 * Release all allocated IDs
+	 */
+	void clear();
+
+	/**
+	 * Get the amount of already allocated IDs
+	 * 
+	 * @return allocated ids count
+	 */
+	int getAllocatedIDs();
+
+	/**
+	 * Get the amount of IDs remaining to be allocated
+	 * 
+	 * @return free ids count
+	 */
+	int getFreeIDs();
+}

l2jserver2-common/src/main/java/com/l2jserver/model/id/object/allocator/IDAllocatorException.java

@@ -0,0 +1,62 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver 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.
+ *
+ * l2jserver 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 l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.model.id.object.allocator;
+
+/**
+ * Exception thrown by an {@link IDAllocator}.
+ * 
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public class IDAllocatorException extends RuntimeException {
+	/**
+	 * The Java Serialization Serial
+	 */
+	private static final long serialVersionUID = 111195059766878062L;
+
+	/**
+	 * Creates an empty instance of this exception
+	 */
+	public IDAllocatorException() {
+		super();
+	}
+
+	/**
+	 * @param message
+	 *            the message
+	 * @param cause
+	 *            the root cause
+	 */
+	public IDAllocatorException(String message, Throwable cause) {
+		super(message, cause);
+	}
+
+	/**
+	 * @param message
+	 *            the message
+	 */
+	public IDAllocatorException(String message) {
+		super(message);
+	}
+
+	/**
+	 * @param cause
+	 *            the root cause
+	 */
+	public IDAllocatorException(Throwable cause) {
+		super(cause);
+	}
+}

l2jserver2-common/src/main/java/com/l2jserver/model/id/provider/CompoundIDProvider.java

@@ -0,0 +1,47 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver 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.
+ *
+ * l2jserver 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 l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.model.id.provider;
+
+import com.google.inject.assistedinject.Assisted;
+import com.l2jserver.model.id.ID;
+import com.l2jserver.model.id.compound.AbstractCompoundID;
+
+/**
+ * The ID factory is used to create instances of IDs. It will automatically make
+ * sure the ID is free before allocating it.
+ * 
+ * @param <I1>
+ *            the first compound {@link ID} type
+ * @param <I2>
+ *            the second compound {@link ID} type
+ * @param <T>
+ *            the {@link CompoundIDProvider} type
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public interface CompoundIDProvider<I1 extends ID<?>, I2 extends ID<?>, T extends AbstractCompoundID<I1, I2>> {
+	/**
+	 * Creates the ID object for an <b>EXISTING</b> ID.
+	 * 
+	 * @param id1
+	 *            the first id
+	 * @param id2
+	 *            the second id
+	 * @return the created compound {@link ID}
+	 */
+	T createID(@Assisted("id1") I1 id1, @Assisted("id2") I2 id2);
+
+}

l2jserver2-common/src/main/java/com/l2jserver/model/id/provider/IDProvider.java

@@ -0,0 +1,49 @@
+/*
+ * This file is part of l2jserver <l2jserver.com>.
+ *
+ * l2jserver 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.
+ *
+ * l2jserver 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 l2jserver.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.model.id.provider;
+
+import com.l2jserver.model.id.ID;
+
+/**
+ * ID objects should never be directly instantiated and an provider
+ * implementation must be used to create and generate them.
+ * <p>
+ * 
+ * The ID provider is used to create instances of IDs. It will automatically
+ * make sure the ID is free before allocating it.
+ * <p>
+ * The provider will also make sure only a single instance for each raw ID
+ * exits, that is for any given ID instance for raw value <b>1</b> only a single
+ * object will be created and following calls will always return the same
+ * object.
+ * 
+ * @param <I>
+ *            the raw id type
+ * @param <T>
+ *            the {@link ID} implementation
+ * @author <a href="http://www.rogiel.com">Rogiel</a>
+ */
+public interface IDProvider<I, T extends ID<I>> {
+	/**
+	 * Creates the ID object for an <b>EXISTING</b> ID.
+	 * 
+	 * @param id
+	 *            the raw id value
+	 * @return the resolved {@link ID} object
+	 */
+	T resolveID(I id);
+}