/*
* JBoss, Home of Professional Open Source
* Copyright 2005, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.resource.adapter.jdbc;

import java.sql.SQLException;

import org.jboss.logging.Logger;
import org.jboss.util.LRUCachePolicy;

/**
 * LRU cache for PreparedStatements.  When ps ages out, close it.
 *
 * @author <a href="mailto:bill@jboss.org">Bill Burke</a>
 * @author <a href="mailto:adrian@jboss.com">Adrian Brock</a>
 * @author Scott.Stark@jboss.org
 * @version $Revision: 1.8 $
 */
public class PreparedStatementCache extends LRUCachePolicy
{
   public static class Key
   {
      public static final int PREPARED_STATEMENT = 1;
      public static final int CALLABLE_STATEMENT = 2;
      private final String sql;
      private final int type;
      private final  int resultSetType;
	  private final int resultSetConcurrency;

       public Key(String sql, int type, int resultSetType, int resultSetConcurrency) {
           this.sql = sql;
           this.type = type;
           this.resultSetType = resultSetType;
           this.resultSetConcurrency = resultSetConcurrency;
       }

       public boolean equals(Object o) {
           if (this == o) return true;
           if (o == null || getClass() != o.getClass()) return false;

           final Key key = (Key) o;

           if (resultSetConcurrency != key.resultSetConcurrency) return false;
           if (resultSetType != key.resultSetType) return false;
           if (type != key.type) return false;
           return !(sql != null ? !sql.equals(key.sql) : key.sql != null);

       }

       public int hashCode() {
           int result;
           result = (sql != null ? sql.hashCode() : 0);
           result = 29 * result + type;
           result = 29 * result + resultSetType;
           result = 29 * result + resultSetConcurrency;
           return result;
       }

       public String toString()
      {
         StringBuffer tmp = new StringBuffer(super.toString());
         tmp.append('[');
         tmp.append("sql=");
         tmp.append(sql);
         tmp.append("type=");
         tmp.append(type==PREPARED_STATEMENT ? "PS" : "CS");
         tmp.append("rstype=");
         tmp.append(resultSetType);
         tmp.append("rsconcur=");
         tmp.append(resultSetConcurrency);
         tmp.append(']');
         return tmp.toString();
      }
   }

   private final Logger log = Logger.getLogger(getClass());

   public PreparedStatementCache(int max)
   {
      super(2, max);
      create();
   }

   protected void ageOut(LRUCachePolicy.LRUCacheEntry entry)
   {
      try
      {
         CachedPreparedStatement ws = (CachedPreparedStatement) entry.m_object;
         ws.agedOut();
      }
      catch (SQLException e)
      {
         log.debug("Failed closing cached statement", e);
      }
      finally
      {
         super.ageOut(entry);
      }
   }
}