/*

 Wotonomy: OpenStep design patterns for pure Java applications.

 Copyright (C) 2001 Michael Powers

 This library 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 library 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 library; if not, see http://www.gnu.org

 */

 package net.wotonomy.control;

 import net.wotonomy.foundation.NSKeyValueCoding;

 import net.wotonomy.foundation.NSMutableDictionary;

 import net.wotonomy.foundation.NSSelector;

 import net.wotonomy.foundation.internal.WotonomyException;

 /**

 * EOKeyValueQualifier performs a property-based

 * comparison against a specified value.  The comparison 

 * is specified in the form of a NSSelector.  The

 * selector is expected to take two arguments, the

 * property value on an object and the comparison value, 

 * and return a Boolean indicating whether the object

 * is qualified.  EOQualifier defines selectors that 

 * may be used in creating EOKeyValueQualifiers.

 *

 * @author michael@mpowers.net

 * @author yjcheung@intersectsoft.com

 * @author $Author: cgruber $

 * @version $Revision: 894 $

 */

 public class EOKeyValueQualifier extends EOQualifier

         implements EOKeyValueArchiving, EOQualifierEvaluation

 {

     private String key;

     private NSSelector selector;

     private Object value;

     /**

     * Constructor specifying a property key, a selector,

     * and a value for comparison.  The selector may be

     * one of the constant selectors defined on EOQualifier.

     */

     public EOKeyValueQualifier(

         String aKey,

         NSSelector aSelector,

         Object aValue )

     {

         key = aKey;

         selector = aSelector;

         value = aValue;

     }

     /**

     * Returns the key for this qualifier.

     */

     public String key()

     {

         return key;

     }

     /**

     * Returns the selector for this qualifier.

     */

     public NSSelector selector()

     {

         return selector;

     }

     /**

     * Returns the value for this qualifier.

     */

     public Object value()

     {

         return value;

     }

     /**

     * Evaluates this qualifier for the specified object,

     * and returns whether the object is qualified.

     * selector() is invoked on the value for key() on the

     * specified object, with value() as the parameter.

     */

     public boolean evaluateWithObject( Object anObject )

     {

         try

         {

             Object value;

             if ( anObject instanceof EOKeyValueCoding )

             {

                 value = ((EOKeyValueCoding)anObject).valueForKey( key() );

             }

             else

             {

                 value = EOKeyValueCodingSupport.valueForKey( anObject, key() );

             }

             return ((Boolean)selector.invoke( value(), value)).booleanValue();

         }

         catch ( Exception exc )

         {

             throw new WotonomyException( exc );

         }

     }

     /**

     * Returns a string representation of this qualifier.

     */

     public String toString()

     {

         return "( " + key + " " + selector + " " + value + " )";

     }

         public void encodeWithKeyValueArchiver(EOKeyValueArchiver arch) {

                 arch.encodeObject("EOKeyValueQualifier", "class");

                 arch.encodeObject(key, "key");

                 NSMutableDictionary d = new NSMutableDictionary(2);

                 if (value instanceof String)

                         d.setObjectForKey("NSString", "class");

                 else if (value instanceof java.math.BigDecimal)

                         d.setObjectForKey("NSDecimalNumber", "class");

                 else if (value instanceof Number)

                         d.setObjectForKey("NSNumber", "class");

                 else if (value instanceof NSKeyValueCoding.Null)

                         d.setObjectForKey("EONull", "class");

                 if (value != null && !(value instanceof NSKeyValueCoding.Null))

                         d.setObjectForKey(value.toString(), "value");

                 arch.encodeObject(d, "value");

                 String selname = null;

                 if (selector.equals(EOQualifier.QualifierOperatorCaseInsensitiveLike))

                         selname = "caseInsensitiveLike:";

                 else if (selector.equals(EOQualifier.QualifierOperatorContains))

                         selname = "contains:";

                 else if (selector.equals(EOQualifier.QualifierOperatorEqual))

                         selname = "isEqualTo:";

                 else if (selector.equals(EOQualifier.QualifierOperatorGreaterThan))

                         selname = "greaterThan:";

                 else if (selector.equals(EOQualifier.QualifierOperatorGreaterThanOrEqualTo))

                         selname = "greaterThanOrEqualTo:";

                 else if (selector.equals(EOQualifier.QualifierOperatorLessThan))

                         selname = "lessThan:";

                 else if (selector.equals(EOQualifier.QualifierOperatorLessThanOrEqualTo))

                         selname = "lessThanOrEqualTo:";

                 else if (selector.equals(EOQualifier.QualifierOperatorLike))

                         selname = "like:";

                 else if (selector.equals(EOQualifier.QualifierOperatorNotEqual))

                         selname = "isNotEqualTo:";

                 else

                         selname = selector.name() + ":";

                 arch.encodeObject(selname, "selectorName");

         }

         public static Object decodeWithKeyValueUnarchiver(EOKeyValueUnarchiver arch) {

                 String k = (String)arch.decodeObjectForKey("key");

                 Object v = arch.decodeObjectForKey("value");

                 NSSelector sel = null;

                 String sname = (String)arch.decodeObjectForKey("selectorName");

                 if (sname.equals("isEqualTo:"))

                         sel = EOQualifier.QualifierOperatorEqual;

                 else if (sname.equals("isNotEqualTo:"))

                         sel = EOQualifier.QualifierOperatorNotEqual;

                 else if (sname.equals("caseInsensitiveLike:"))

                         sel = EOQualifier.QualifierOperatorCaseInsensitiveLike;

                 else if (sname.equals("contains:"))

                         sel = EOQualifier.QualifierOperatorContains;

                 else if (sname.equals("greaterThan:"))

                         sel = EOQualifier.QualifierOperatorGreaterThan;

                 else if (sname.equals("greaterThanOrEqualTo:"))

                         sel = EOQualifier.QualifierOperatorGreaterThanOrEqualTo;

                 else if (sname.equals("lessThan:"))

                         sel = EOQualifier.QualifierOperatorLessThan;

                 else if (sname.equals("lessThanOrEqualTo:"))

                         sel = EOQualifier.QualifierOperatorLessThanOrEqualTo;

                 else if (sname.equals("like:"))

                         sel = EOQualifier.QualifierOperatorLike;

                 EOKeyValueQualifier q = new EOKeyValueQualifier(k, sel, v);

                 return q;

         }

 }

 /*

  * $Log$

  * Revision 1.2  2006/02/16 16:47:14  cgruber

  * Move some classes in to "internal" packages and re-work imports, etc.

  *

  * Also use UnsupportedOperationExceptions where appropriate, instead of WotonomyExceptions.

  *

  * Revision 1.1  2006/02/16 13:19:57  cgruber

  * Check in all sources in eclipse-friendly maven-enabled packages.

  *

  * Revision 1.10  2003/08/12 01:43:04  chochos

  * formally implement EOQualifierEvaluation

  *

  * Revision 1.9  2003/08/11 19:39:30  chochos

  * special conditions for NSKeyValueCoding.NullValue -> EONull

  *

  * Revision 1.8  2003/08/09 01:22:51  chochos

  * qualifiers implement EOKeyValueArchiving

  *

  * Revision 1.7  2003/08/06 23:07:52  chochos

  * general code cleanup (mostly, removing unused imports)

  *

  * Revision 1.6  2001/10/31 15:26:06  mpowers

  * Fixed typo.

  *

  * Revision 1.5  2001/10/31 15:25:14  mpowers

  * Cleanup of qualifiers.

  *

  * Revision 1.4  2001/10/30 22:57:28  mpowers

  * EOQualifier framework is now working.

  *

  * Revision 1.3  2001/09/13 15:25:56  mpowers

  * Started implementation of the EOQualifier framework.

  *

  * Revision 1.2  2001/03/29 03:29:49  mpowers

  * Now using KeyValueCoding and Support instead of Introspector.

  *

  * Revision 1.1  2001/02/27 03:33:04  mpowers

  * Initial draft of the key-value qualifier.

  *

  *

  */