package org.apache.torque.om;
   
   /* ====================================================================
    * The Apache Software License, Version 1.1
    *
    * Copyright (c) 2001-2003 The Apache Software Foundation.  All rights
    * reserved.
    *
    * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. The end-user documentation included with the redistribution,
   *    if any, must include the following acknowledgment:
   *       "This product includes software developed by the
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowledgment may appear in the software itself,
   *    if and wherever such third-party acknowledgments normally appear.
   *
   * 4. The names "Apache" and "Apache Software Foundation" and
   *    "Apache Turbine" must not be used to endorse or promote products
   *    derived from this software without prior written permission. For
   *    written permission, please contact apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache",
   *    "Apache Turbine", nor may "Apache" appear in their name, without
   *    prior written permission of the Apache Software Foundation.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   */
  
  import java.io.Serializable;
  import java.sql.Connection;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import org.apache.torque.TorqueException;
  
  /***
   * This class contains attributes and methods that are used by all
   * business objects within the system.
   *
   * @author <a href="mailto:frank.kim@clearink.com">Frank Y. Kim</a>
   * @author <a href="mailto:jmcnally@collab.net">John D. McNally</a>
   * @version $Id: BaseObject.java,v 1.18 2003/05/14 19:38:04 mpoeschl Exp $
   */
  public abstract class BaseObject implements Persistent, Serializable
  {
      /*** The constant denoting an unset numeric database identifier. */
      public static final int NEW_ID = -1;
  
      /***
       * Shared portion of the error message thrown for methods which
       * are not implemented.
       */
      private static final String NOT_IMPLEMENTED
              = "Not implemented: Method must be overridden if called";
  
      /*** attribute to determine if this object has previously been saved. */
      private boolean isNew = true;
  
      /*** The unique id for the object which can be used for persistence. */
      private ObjectKey primaryKey = null;
  
      /***
       * A flag that indicates an object has been modified since it was
       * last retrieved from the persistence mechanism.  This flag is
       * used to determine if this object should be saved to the
       * database.  We initialize it to true to force new objects to be
       * saved.
       */
      private boolean modified = true;
  
     /*** Cache the log to avoid looking it up every time its needed. */
     private transient Log log = null;
 
     /***
      * getter for the object primaryKey.
      *
      * @return the object primaryKey as an Object
      */
     public ObjectKey getPrimaryKey()
     {
         return primaryKey;
     }
 
     /***
      * Returns whether the object has been modified.
      *
      * @return True if the object has been modified.
      */
     public boolean isModified()
     {
         return modified;
     }
 
     /***
      * Returns whether the object has ever been saved.  This will
      * be false, if the object was retrieved from storage or was created
      * and then saved.
      *
      * @return true, if the object has never been persisted.
      */
     public boolean isNew()
     {
         return isNew;
     }
 
     /***
      * Setter for the isNew attribute.  This method will be called
      * by Torque-generated children and Peers.
      *
      * @param b the state of the object.
      */
     public void setNew(boolean b)
     {
         this.isNew = b;
     }
 
     /***
      * Sets the PrimaryKey for the object.
      *
      * @param primaryKey The new PrimaryKey for the object.
      * @exception TorqueException This method will not throw any exceptions
      * but this allows for children to override the method more easily
      */
     public void setPrimaryKey(String primaryKey) throws TorqueException
     {
         this.primaryKey = new StringKey(primaryKey);
     }
 
     /***
      * Sets the PrimaryKey for the object as an Object.
      *
      * @param primaryKey The new PrimaryKey for the object.
      * @exception TorqueException This method will not throw any exceptions
      * but this allows for children to override the method more easily
      */
     public void setPrimaryKey(SimpleKey[] primaryKey) throws TorqueException
     {
         this.primaryKey = new ComboKey(primaryKey);
     }
 
     /***
      * Sets the PrimaryKey for the object as an Object.
      *
      * @param primaryKey The new PrimaryKey for the object.
      * @exception TorqueException This method will not throw any exceptions
      * but this allows for children to override the method more easily
      */
     public void setPrimaryKey(ObjectKey primaryKey) throws TorqueException
     {
         this.primaryKey = primaryKey;
     }
 
     /***
      * Sets the modified state for the object.
      *
      * @param m The new modified state for the object.
      */
     public void setModified(boolean m)
     {
         modified = m;
     }
 
     /***
      * Sets the modified state for the object to be false.
      */
     public void resetModified()
     {
         modified = false;
     }
 
     /***
      * Retrieves a field from the object by name. Must be overridden if called.
      * BaseObject's implementation will throw an Error.
      *
      * @param field The name of the field to retrieve.
      * @return The retrieved field value
      *
      */
     public Object getByName(String field)
     {
         throw new Error("BaseObject.getByName: " + NOT_IMPLEMENTED);
     }
 
     /***
      * Retrieves a field from the object by name passed in
      * as a String.  Must be overridden if called.
      * BaseObject's implementation will throw an Error.
      *
      * @param name field name
      * @return value of the field
      */
     public Object getByPeerName(String name)
     {
         throw new Error("BaseObject.getByPeerName: " + NOT_IMPLEMENTED);
     }
 
     /***
      * Retrieves a field from the object by position as specified
      * in a database schema for example.  Must be overridden if called.
      * BaseObject's implementation will throw an Error.
      *
      * @param pos field position
      * @return value of the field
      */
     public Object getByPosition(int pos)
     {
         throw new Error("BaseObject.getByPosition: " + NOT_IMPLEMENTED);
     }
 
     /***
      * Compares this with another <code>BaseObject</code> instance.  If
      * <code>obj</code> is an instance of <code>BaseObject</code>, delegates to
      * <code>equals(BaseObject)</code>.  Otherwise, returns <code>false</code>.
      *
      * @param obj The object to compare to.
      * @return    Whether equal to the object specified.
      */
     public boolean equals(Object obj)
     {
         if (obj != null && obj instanceof BaseObject)
         {
             return equals((BaseObject) obj);
         }
         else
         {
             return false;
         }
     }
 
     /***
      * Compares the primary key of this instance with the key of another.
      *
      * @param bo The object to compare to.
      * @return   Whether the primary keys are equal.
      */
     public boolean equals(BaseObject bo)
     {
         if (bo == null)
         {
             return false;
         }
         if (this == bo)
         {
             return true;
         }
         else if (getPrimaryKey() == null || bo.getPrimaryKey() == null)
         {
             return false;
         }
         else
         {
             return getPrimaryKey().equals(bo.getPrimaryKey());
         }
     }
 
     /***
      * If the primary key is not <code>null</code>, return the hashcode of the
      * primary key.  Otherwise calls <code>Object.hashCode()</code>.
      *
      * @return an <code>int</code> value
      */
     public int hashCode()
     {
         ObjectKey ok = getPrimaryKey();
         if (ok == null)
         {
             return super.hashCode();
         }
 
         return ok.hashCode();
     }
 
     /***
      * gets a commons-logging Log based on class name.
      *
      * @return a <code>Log</code> to write log to.
      * @deprecated Use getLog()
      */
     protected Log log()
     {
         return getLog();
     }
 
     /***
      * gets a commons-logging Log based on class name.
      *
      * @return a <code>Log</code> to write log to.
      */
     protected Log getLog()
     {
         if (log == null)
         {
             log = LogFactory.getLog(getClass().getName());
         }
         return log;
     }
 
     /***
      * @see org.apache.torque.om.Persistent#save()
      */
     public abstract void save() throws Exception;
 
     /***
      * @see org.apache.torque.om.Persistent#save(String)
      */
     public abstract void save(String dbName) throws Exception;
 
     /***
      * @see org.apache.torque.om.Persistent#save(Connection)
      */
     public abstract void save(Connection con) throws Exception;
 }