package org.apache.ojb.otm.lock.map;

 /* Copyright 2003-2005 The Apache Software Foundation

  *

  * Licensed under the Apache License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  *     http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 import java.util.Iterator;

 import java.util.HashMap;

 import java.util.Map;

 import org.apache.ojb.broker.Identity;

 import org.apache.ojb.otm.lock.ObjectLock;

 /**

  *

  * <javadoc>

  *

  * @author <a href="mailto:rraghuram@hotmail.com">Raghu Rajah</a>

  *

  */

 public class InMemoryLockMap implements LockMap

 {

     private HashMap _locks;

     public InMemoryLockMap ()

     {

         _locks = new HashMap();

     }

     /**

      *

      * @see org.apache.ojb.otm.lock.map.LockMap#getLock(Identity)

      *

      */

     public ObjectLock getLock(Identity oid)

     {

         ObjectLock lock;

         synchronized (_locks)

         {

             lock = (ObjectLock) _locks.get(oid);

             if (lock == null)

             {

                 lock = new ObjectLock(oid);

                 _locks.put(oid, lock);

             }

         }

         return lock;

     }

     public void gc()

     {

         synchronized (_locks)

         {

             for (Iterator it = _locks.entrySet().iterator(); it.hasNext(); )

             {

                 Map.Entry entry = (Map.Entry) it.next();

                 ObjectLock lock = (ObjectLock) entry.getValue();

                 if (lock.isFree())

                 {

                     it.remove();

                 }

             }

         }

     }

     public String toString()

     {

         return _locks.toString();

     }

 }