AbstractClassIndexStrategy.java :  » Database-DBMS » db4o-6.4 » com » db4o » internal » classindex » Java Open Source

/* Copyright (C) 2004 - 2007  db4objects Inc.  http://www.db4o.com

This file is part of the db4o open source object database.

db4o is free software; you can redistribute it and/or modify it under
the terms of version 2 of the GNU General Public License as published
by the Free Software Foundation and as clarified by db4objects' GPL 
interpretation policy, available at
http://www.db4o.com/about/company/legalpolicies/gplinterpretation/
Alternatively you can write to db4objects, Inc., 1900 S Norfolk Street,
Suite 350, San Mateo, CA 94403, USA.

db4o 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, write to the Free Software Foundation, Inc.,
59 Temple Place - Suite 330, Boston, MA  02111-1307, USA. */
package com.db4o.internal.classindex;

import com.db4o.*;
import com.db4o.internal.*;

/**
 * @exclude
 */
public abstract class AbstractClassIndexStrategy implements ClassIndexStrategy {

  protected final ClassMetadata _yapClass;

  public AbstractClassIndexStrategy(ClassMetadata yapClass) {
    _yapClass = yapClass;
  }

  protected int yapClassID() {
    return _yapClass.getID();
  }

  public int ownLength() {
    return Const4.ID_LENGTH;
  }

  protected abstract void internalAdd(Transaction trans, int id);

  public final void add(Transaction trans, int id) {
    if (DTrace.enabled) {
          DTrace.ADD_TO_CLASS_INDEX.log(id);
      }
    checkId(id);
    internalAdd(trans, id);
  }  

  protected abstract void internalRemove(Transaction ta, int id);

  public final void remove(Transaction ta, int id) {
      if (DTrace.enabled){
          DTrace.REMOVE_FROM_CLASS_INDEX.log(id);
      }
      checkId(id);
      internalRemove(ta, id);
  }
  
  private void checkId(int id) {
    if (Deploy.debug) {
            if (id == 0) {
                throw new IllegalArgumentException("id can't be zero");
            }
        }
  }
}