/*
    * $Header: /cvsroot/valuelist/valuelist/src/java/net/mlw/vlh/adapter/jdbc/dynabean/fix/ResultSetIterator.java,v 1.1 2004/06/03 14:27:13 mlavwilson Exp $
    * $Revision: 1.1 $
    * $Date: 2004/06/03 14:27:13 $
    *
    * ====================================================================
    * 
    * 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
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   *    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 acknowledgement:  
   *       "This product includes software developed by the 
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowledgement may appear in the software itself,
   *    if and wherever such third-party acknowledgements normally appear.
   *
   * 4. The names "Apache", "The Jakarta Project", "Commons", and "Apache Software
   *    Foundation" must not be used to endorse or promote products derived
   *    from this software without prior written permission. For written 
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   * 5. Products derived from this software may not be called "Apache",
   *    "Apache" nor may "Apache" appear in their names without prior 
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   * This software consists of voluntary contributions made by many
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   */ 
  
  
  package net.mlw.vlh.adapter.jdbc.dynabean.fix;
  
  
  import java.sql.SQLException;
  import java.util.Iterator;
  import java.util.NoSuchElementException;
  
  import org.apache.commons.beanutils.DynaBean;
  import org.apache.commons.beanutils.DynaClass;
  
  
  /***
   * <p>Implementation of <code>java.util.Iterator</code> returned by the
   * <code>iterator()</code> method of {@link ResultSetDynaClass}.  Each
   * object returned by this iterator will be a {@link DynaBean} that
   * represents a single row from the result set being wrapped.</p>
   *
   * @author Craig R. McClanahan
   * @version $Revision: 1.1 $ $Date: 2004/06/03 14:27:13 $
   */
  
  public class ResultSetIterator implements DynaBean, Iterator {
  
  
      // ------------------------------------------------------------ Constructor
  
  
      /***
       * <p>Construct an <code>Iterator</code> for the result set being wrapped
       * by the specified {@link ResultSetDynaClass}.</p>
       *
       * @param dynaClass The {@link ResultSetDynaClass} wrapping the
       *  result set we will iterate over
       */
      ResultSetIterator(ResultSetDynaClass dynaClass) {
  
          this.dynaClass = dynaClass;
 
     }
 
 
     // ----------------------------------------------------- Instance Variables
 
 
 
     /***
      * <p>Flag indicating whether the result set is currently positioned at a
      * row for which we have not yet returned an element in the iteration.</p>
      */
     protected boolean current = false;
 
 
     /***
      * <p>The {@link ResultSetDynaClass} we are associated with.</p>
      */
     protected ResultSetDynaClass dynaClass = null;
 
 
     /***
      * <p>Flag indicating whether the result set has indicated that there are
      * no further rows.</p>
      */
     protected boolean eof = false;
 
 
     // ------------------------------------------------------- DynaBean Methods
 
 
     /***
      * Does the specified mapped property contain a value for the specified
      * key value?
      *
      * @param name Name of the property to check
      * @param key Name of the key to check
      *
      * @exception IllegalArgumentException if there is no property
      *  of the specified name
      */
     public boolean contains(String name, String key) {
 
         throw new UnsupportedOperationException
             ("FIXME - mapped properties not currently supported");
 
     }
 
 
     /***
      * Return the value of a simple property with the specified name.
      *
      * @param name Name of the property whose value is to be retrieved
      *
      * @exception IllegalArgumentException if there is no property
      *  of the specified name
      */
     public Object get(String name) {
 
         if (dynaClass.getDynaProperty(name) == null) {
             throw new IllegalArgumentException(name);
         }
         try {
             return (dynaClass.getResultSet().getObject(name));
         } catch (SQLException e) {
             return null;
         }
 
     }
 
 
     /***
      * Return the value of an indexed property with the specified name.
      *
      * @param name Name of the property whose value is to be retrieved
      * @param index Index of the value to be retrieved
      *
      * @exception IllegalArgumentException if there is no property
      *  of the specified name
      * @exception IllegalArgumentException if the specified property
      *  exists, but is not indexed
      * @exception IndexOutOfBoundsException if the specified index
      *  is outside the range of the underlying property
      * @exception NullPointerException if no array or List has been
      *  initialized for this property
      */
     public Object get(String name, int index) {
 
         throw new UnsupportedOperationException
             ("FIXME - indexed properties not currently supported");
 
     }
 
 
     /***
      * Return the value of a mapped property with the specified name,
      * or <code>null</code> if there is no value for the specified key.
      *
      * @param name Name of the property whose value is to be retrieved
      * @param key Key of the value to be retrieved
      *
      * @exception IllegalArgumentException if there is no property
      *  of the specified name
      * @exception IllegalArgumentException if the specified property
      *  exists, but is not mapped
      */
     public Object get(String name, String key) {
 
         throw new UnsupportedOperationException
             ("FIXME - mapped properties not currently supported");
 
     }
 
 
     /***
      * Return the <code>DynaClass</code> instance that describes the set of
      * properties available for this DynaBean.
      */
     public DynaClass getDynaClass() {
 
         return (this.dynaClass);
 
     }
 
 
     /***
      * Remove any existing value for the specified key on the
      * specified mapped property.
      *
      * @param name Name of the property for which a value is to
      *  be removed
      * @param key Key of the value to be removed
      *
      * @exception IllegalArgumentException if there is no property
      *  of the specified name
      */
     public void remove(String name, String key) {
 
         throw new UnsupportedOperationException
             ("FIXME - mapped operations not currently supported");
 
     }
 
 
     /***
      * Set the value of a simple property with the specified name.
      *
      * @param name Name of the property whose value is to be set
      * @param value Value to which this property is to be set
      *
      * @exception ConversionException if the specified value cannot be
      *  converted to the type required for this property
      * @exception IllegalArgumentException if there is no property
      *  of the specified name
      * @exception NullPointerException if an attempt is made to set a
      *  primitive property to null
      */
     public void set(String name, Object value) {
 
         if (dynaClass.getDynaProperty(name) == null) {
             throw new IllegalArgumentException(name);
         }
         try {
             dynaClass.getResultSet().updateObject(name, value);
         } catch (SQLException e) {
             throw new RuntimeException
                 ("set(" + name + "): SQLException: " + e);
         }
 
     }
 
 
     /***
      * Set the value of an indexed property with the specified name.
      *
      * @param name Name of the property whose value is to be set
      * @param index Index of the property to be set
      * @param value Value to which this property is to be set
      *
      * @exception ConversionException if the specified value cannot be
      *  converted to the type required for this property
      * @exception IllegalArgumentException if there is no property
      *  of the specified name
      * @exception IllegalArgumentException if the specified property
      *  exists, but is not indexed
      * @exception IndexOutOfBoundsException if the specified index
      *  is outside the range of the underlying property
      */
     public void set(String name, int index, Object value) {
 
         throw new UnsupportedOperationException
             ("FIXME - indexed properties not currently supported");
 
     }
 
 
     /***
      * Set the value of a mapped property with the specified name.
      *
      * @param name Name of the property whose value is to be set
      * @param key Key of the property to be set
      * @param value Value to which this property is to be set
      *
      * @exception ConversionException if the specified value cannot be
      *  converted to the type required for this property
      * @exception IllegalArgumentException if there is no property
      *  of the specified name
      * @exception IllegalArgumentException if the specified property
      *  exists, but is not mapped
      */
     public void set(String name, String key, Object value) {
 
         throw new UnsupportedOperationException
             ("FIXME - mapped properties not currently supported");
 
     }
 
 
     // ------------------------------------------------------- Iterator Methods
 
 
     /***
      * <p>Return <code>true</code> if the iteration has more elements.</p>
      */
     public boolean hasNext() {
 
         try {
             advance();
             return (!eof);
         } catch (SQLException e) {
             throw new RuntimeException("hasNext():  SQLException:  " + e);
         }
 
     }
 
 
     /***
      * <p>Return the next element in the iteration.</p>
      */
     public Object next() {
 
         try {
             advance();
             if (eof) {
                 throw new NoSuchElementException();
             }
             current = false;
             return (this);
         } catch (SQLException e) {
             throw new RuntimeException("next():  SQLException:  " + e);
         }
 
     }
 
 
     /***
      * <p>Remove the current element from the iteration.  This method is
      * not supported.</p>
      */
     public void remove() {
 
         throw new UnsupportedOperationException("remove()");
 
     }
 
 
     // ------------------------------------------------------ Protected Methods
 
 
     /***
      * <p>Advance the result set to the next row, if there is not a current
      * row (and if we are not already at eof).</p>
      *
      * @exception SQLException if the result set throws an exception
      */
     protected void advance() throws SQLException {
 
         if (!current && !eof) {
             if (dynaClass.getResultSet().next()) {
                 current = true;
                 eof = false;
             } else {
                 current = false;
                 eof = true;
             }
         }
 
     }
 
 
 }