ResultSetIterator.java Source code

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import java.beans.BeanInfo;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Timestamp;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

/**
 * <p>
 * Wraps a <code>ResultSet</code> in an <code>Iterator</code>.  This is useful
 * when you want to present a non-database application layer with domain
 * neutral data.
 * </p>
 * 
 * <p>
 * This implementation requires the <code>ResultSet.isLast()</code> method
 * to be implemented.
 * </p>
 */
public class ResultSetIterator implements Iterator {

    /**
     * The wrapped <code>ResultSet</code>.
     */
    private final ResultSet rs;

    /**
     * The processor to use when converting a row into an Object[].
     */
    private final RowProcessor convert;

    /**
     * Constructor for ResultSetIterator.
     * @param rs Wrap this <code>ResultSet</code> in an <code>Iterator</code>.
     */
    public ResultSetIterator(ResultSet rs) {
        this(rs, new BasicRowProcessor());
    }

    /**
     * Constructor for ResultSetIterator.
     * @param rs Wrap this <code>ResultSet</code> in an <code>Iterator</code>.
     * @param convert The processor to use when converting a row into an 
     * <code>Object[]</code>.  Defaults to a 
     * <code>BasicRowProcessor</code>.
     */
    public ResultSetIterator(ResultSet rs, RowProcessor convert) {
        this.rs = rs;
        this.convert = convert;
    }

    /**
     * Returns true if there are more rows in the ResultSet.
     * @return boolean <code>true</code> if there are more rows
     * @throws RuntimeException if an SQLException occurs.
     */
    public boolean hasNext() {
        try {
            return !rs.isLast();
        } catch (SQLException e) {
            rethrow(e);
            return false;
        }
    }

    /**
     * Returns the next row as an <code>Object[]</code>.
     * @return An <code>Object[]</code> with the same number of elements as
     * columns in the <code>ResultSet</code>. 
     * @see java.util.Iterator#next()
     * @throws RuntimeException if an SQLException occurs.
     */
    public Object next() {
        try {
            rs.next();
            return this.convert.toArray(rs);
        } catch (SQLException e) {
            rethrow(e);
            return null;
        }
    }

    /**
     * Deletes the current row from the <code>ResultSet</code>.
     * @see java.util.Iterator#remove()
     * @throws RuntimeException if an SQLException occurs.
     */
    public void remove() {
        try {
            this.rs.deleteRow();
        } catch (SQLException e) {
            rethrow(e);
        }
    }

    /**
     * Rethrow the SQLException as a RuntimeException.  This implementation
     * creates a new RuntimeException with the SQLException's error message.
     * @param e SQLException to rethrow
     * @since DbUtils 1.1
     */
    protected void rethrow(SQLException e) {
        throw new RuntimeException(e.getMessage());
    }

}

/**
 * <code>RowProcessor</code> implementations convert 
 * <code>ResultSet</code> rows into various other objects.  Implementations
 * can extend <code>BasicRowProcessor</code> to protect themselves
 * from changes to this interface. 
 * 
 * @see BasicRowProcessor
 */
interface RowProcessor {

    /**
     * Create an <code>Object[]</code> from the column values in one 
     * <code>ResultSet</code> row.  The <code>ResultSet</code> should be 
     * positioned on a valid row before passing it to this method.  
     * Implementations of this method must not alter the row position of 
     * the <code>ResultSet</code>. 
     *
     * @param rs ResultSet that supplies the array data
     * @throws SQLException if a database access error occurs
     * @return the newly created array
     */
    public Object[] toArray(ResultSet rs) throws SQLException;

    /**
     * Create a JavaBean from the column values in one <code>ResultSet</code> 
     * row.  The <code>ResultSet</code> should be positioned on a valid row before
     * passing it to this method.  Implementations of this method must not
     * alter the row position of the <code>ResultSet</code>.
     *
     * @param rs ResultSet that supplies the bean data
     * @param type Class from which to create the bean instance
     * @throws SQLException if a database access error occurs
     * @return the newly created bean
     */
    public Object toBean(ResultSet rs, Class type) throws SQLException;

    /**
     * Create a <code>List</code> of JavaBeans from the column values in all 
     * <code>ResultSet</code> rows.  <code>ResultSet.next()</code> should 
     * <strong>not</strong> be called before passing it to this method.
     * 
     * @param rs ResultSet that supplies the bean data
     * @param type Class from which to create the bean instance
     * @throws SQLException if a database access error occurs
     * @return A <code>List</code> of beans with the given type in the order 
     * they were returned by the <code>ResultSet</code>.
     */
    public List toBeanList(ResultSet rs, Class type) throws SQLException;

    /**
     * Create a <code>Map</code> from the column values in one 
     * <code>ResultSet</code> row.  The <code>ResultSet</code> should be 
     * positioned on a valid row before
     * passing it to this method.  Implementations of this method must not
     * alter the row position of the <code>ResultSet</code>.
     *
     * @param rs ResultSet that supplies the map data
     * @throws SQLException if a database access error occurs
     * @return the newly created Map
     */
    public Map toMap(ResultSet rs) throws SQLException;

}

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * Basic implementation of the <code>RowProcessor</code> interface.
 * 
 * <p>
 * This class is thread-safe.
 * </p>
 * 
 * @see RowProcessor
 */
class BasicRowProcessor implements RowProcessor {

    /**
     * The default BeanProcessor instance to use if not supplied in the
     * constructor.
     */
    private static final BeanProcessor defaultConvert = new BeanProcessor();

    /**
     * The Singleton instance of this class.
     */
    private static final BasicRowProcessor instance = new BasicRowProcessor();

    /**
     * Returns the Singleton instance of this class.
     *
     * @return The single instance of this class.
     * @deprecated Create instances with the constructors instead.  This will 
     * be removed after DbUtils 1.1.
     */
    public static BasicRowProcessor instance() {
        return instance;
    }

    /**
     * Use this to process beans.
     */
    private final BeanProcessor convert;

    /**
     * BasicRowProcessor constructor.  Bean processing defaults to a 
     * BeanProcessor instance.
     */
    public BasicRowProcessor() {
        this(defaultConvert);
    }

    /**
     * BasicRowProcessor constructor.
     * @param convert The BeanProcessor to use when converting columns to 
     * bean properties.
     * @since DbUtils 1.1
     */
    public BasicRowProcessor(BeanProcessor convert) {
        super();
        this.convert = convert;
    }

    /**
     * Convert a <code>ResultSet</code> row into an <code>Object[]</code>.
     * This implementation copies column values into the array in the same 
     * order they're returned from the <code>ResultSet</code>.  Array elements
     * will be set to <code>null</code> if the column was SQL NULL.
     *
     * @see org.apache.commons.dbutils.RowProcessor#toArray(java.sql.ResultSet)
     */
    public Object[] toArray(ResultSet rs) throws SQLException {
        ResultSetMetaData meta = rs.getMetaData();
        int cols = meta.getColumnCount();
        Object[] result = new Object[cols];

        for (int i = 0; i < cols; i++) {
            result[i] = rs.getObject(i + 1);
        }

        return result;
    }

    /**
     * Convert a <code>ResultSet</code> row into a JavaBean.  This 
     * implementation delegates to a BeanProcessor instance.
     * @see org.apache.commons.dbutils.RowProcessor#toBean(java.sql.ResultSet, java.lang.Class)
     * @see org.apache.commons.dbutils.BeanProcessor#toBean(java.sql.ResultSet, java.lang.Class) 
     */
    public Object toBean(ResultSet rs, Class type) throws SQLException {
        return this.convert.toBean(rs, type);
    }

    /**
     * Convert a <code>ResultSet</code> into a <code>List</code> of JavaBeans.  
     * This implementation delegates to a BeanProcessor instance. 
     * @see org.apache.commons.dbutils.RowProcessor#toBeanList(java.sql.ResultSet, java.lang.Class)
     * @see org.apache.commons.dbutils.BeanProcessor#toBeanList(java.sql.ResultSet, java.lang.Class)
     */
    public List toBeanList(ResultSet rs, Class type) throws SQLException {
        return this.convert.toBeanList(rs, type);
    }

    /**
     * Convert a <code>ResultSet</code> row into a <code>Map</code>.  This 
     * implementation returns a <code>Map</code> with case insensitive column
     * names as keys.  Calls to <code>map.get("COL")</code> and 
     * <code>map.get("col")</code> return the same value.
     * @see org.apache.commons.dbutils.RowProcessor#toMap(java.sql.ResultSet)
     */
    public Map toMap(ResultSet rs) throws SQLException {
        Map result = new CaseInsensitiveHashMap();
        ResultSetMetaData rsmd = rs.getMetaData();
        int cols = rsmd.getColumnCount();

        for (int i = 1; i <= cols; i++) {
            result.put(rsmd.getColumnName(i), rs.getObject(i));
        }

        return result;
    }

    /**
     * A Map that converts all keys to lowercase Strings for case insensitive
     * lookups.  This is needed for the toMap() implementation because 
     * databases don't consistenly handle the casing of column names. 
     * 
     * <p>The keys are stored as they are given [BUG #DBUTILS-34], so we maintain
     * an internal mapping from lowercase keys to the real keys in order to 
     * achieve the case insensitive lookup.
     * 
     * <p>Note: This implementation does not allow <tt>null</tt>
     * for key, whereas {@link HashMap} does, because of the code:
     * <pre>
     * key.toString().toLowerCase()
     * </pre>
     */
    private static class CaseInsensitiveHashMap extends HashMap {

        /**
         * The internal mapping from lowercase keys to the real keys.
         * 
         * <p>
         * Any query operation using the key 
         * ({@link #get(Object)}, {@link #containsKey(Object)})
         * is done in three steps:
         * <ul>
         * <li>convert the parameter key to lower case</li>
         * <li>get the actual key that corresponds to the lower case key</li>
         * <li>query the map with the actual key</li>
         * </ul>
         * </p>
         */
        private final Map lowerCaseMap = new HashMap();

        /**
         * Required for serialization support.
         * 
         * @see java.io.Serializable
         */
        private static final long serialVersionUID = 1841673097701957808L;

        /**
         * @see java.util.Map#containsKey(java.lang.Object)
         */
        public boolean containsKey(Object key) {
            Object realKey = lowerCaseMap.get(key.toString().toLowerCase());
            return super.containsKey(realKey);
            // Possible optimisation here:
            // Since the lowerCaseMap contains a mapping for all the keys,
            // we could just do this:
            // return lowerCaseMap.containsKey(key.toString().toLowerCase());
        }

        /**
         * @see java.util.Map#get(java.lang.Object)
         */
        public Object get(Object key) {
            Object realKey = lowerCaseMap.get(key.toString().toLowerCase());
            return super.get(realKey);
        }

        /**
         * @see java.util.Map#put(java.lang.Object, java.lang.Object)
         */
        public Object put(Object key, Object value) {
            /*
             * In order to keep the map and lowerCaseMap synchronized,
             * we have to remove the old mapping before putting the 
             * new one. Indeed, oldKey and key are not necessaliry equals.
             * (That's why we call super.remove(oldKey) and not just
             * super.put(key, value))
             */
            Object oldKey = lowerCaseMap.put(key.toString().toLowerCase(), key);
            Object oldValue = super.remove(oldKey);
            super.put(key, value);
            return oldValue;
        }

        /**
         * @see java.util.Map#putAll(java.util.Map)
         */
        public void putAll(Map m) {
            Iterator iter = m.entrySet().iterator();
            while (iter.hasNext()) {
                Map.Entry entry = (Map.Entry) iter.next();
                Object key = entry.getKey();
                Object value = entry.getValue();
                this.put(key, value);
            }
        }

        /**
         * @see java.util.Map#remove(java.lang.Object)
         */
        public Object remove(Object key) {
            Object realKey = lowerCaseMap.remove(key.toString().toLowerCase());
            return super.remove(realKey);
        }
    }

}

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * <p>
 * <code>BeanProcessor</code> matches column names to bean property names 
 * and converts <code>ResultSet</code> columns into objects for those bean 
 * properties.  Subclasses should override the methods in the processing chain
 * to customize behavior.
 * </p>
 * 
 * <p>
 * This class is thread-safe.
 * </p>
 * 
 * @see BasicRowProcessor
 * 
 * @since DbUtils 1.1
 */
class BeanProcessor {

    /**
     * Special array value used by <code>mapColumnsToProperties</code> that 
     * indicates there is no bean property that matches a column from a 
     * <code>ResultSet</code>.
     */
    protected static final int PROPERTY_NOT_FOUND = -1;

    /**
     * Set a bean's primitive properties to these defaults when SQL NULL 
     * is returned.  These are the same as the defaults that ResultSet get* 
     * methods return in the event of a NULL column.
     */
    private static final Map primitiveDefaults = new HashMap();

    static {
        primitiveDefaults.put(Integer.TYPE, new Integer(0));
        primitiveDefaults.put(Short.TYPE, new Short((short) 0));
        primitiveDefaults.put(Byte.TYPE, new Byte((byte) 0));
        primitiveDefaults.put(Float.TYPE, new Float(0));
        primitiveDefaults.put(Double.TYPE, new Double(0));
        primitiveDefaults.put(Long.TYPE, new Long(0));
        primitiveDefaults.put(Boolean.TYPE, Boolean.FALSE);
        primitiveDefaults.put(Character.TYPE, new Character('\u0000'));
    }

    /**
     * Constructor for BeanProcessor.
     */
    public BeanProcessor() {
        super();
    }

    /**
     * Convert a <code>ResultSet</code> row into a JavaBean.  This 
     * implementation uses reflection and <code>BeanInfo</code> classes to 
     * match column names to bean property names.  Properties are matched to 
     * columns based on several factors:
     * <br/>
     * <ol>
     *     <li>
     *     The class has a writable property with the same name as a column.
     *     The name comparison is case insensitive.
     *     </li>
     * 
     *     <li>
     *     The column type can be converted to the property's set method 
     *     parameter type with a ResultSet.get* method.  If the conversion fails
     *     (ie. the property was an int and the column was a Timestamp) an
     *     SQLException is thrown.
     *     </li>
     * </ol>
     * 
     * <p>
     * Primitive bean properties are set to their defaults when SQL NULL is
     * returned from the <code>ResultSet</code>.  Numeric fields are set to 0
     * and booleans are set to false.  Object bean properties are set to 
     * <code>null</code> when SQL NULL is returned.  This is the same behavior
     * as the <code>ResultSet</code> get* methods.
     * </p>
     *
     * @param rs ResultSet that supplies the bean data
     * @param type Class from which to create the bean instance
     * @throws SQLException if a database access error occurs
     * @return the newly created bean
     */
    public Object toBean(ResultSet rs, Class type) throws SQLException {

        PropertyDescriptor[] props = this.propertyDescriptors(type);

        ResultSetMetaData rsmd = rs.getMetaData();
        int[] columnToProperty = this.mapColumnsToProperties(rsmd, props);

        return this.createBean(rs, type, props, columnToProperty);
    }

    /**
     * Convert a <code>ResultSet</code> into a <code>List</code> of JavaBeans.  
     * This implementation uses reflection and <code>BeanInfo</code> classes to 
     * match column names to bean property names. Properties are matched to 
     * columns based on several factors:
     * <br/>
     * <ol>
     *     <li>
     *     The class has a writable property with the same name as a column.
     *     The name comparison is case insensitive.
     *     </li>
     * 
     *     <li>
     *     The column type can be converted to the property's set method 
     *     parameter type with a ResultSet.get* method.  If the conversion fails
     *     (ie. the property was an int and the column was a Timestamp) an
     *     SQLException is thrown.
     *     </li>
     * </ol>
     * 
     * <p>
     * Primitive bean properties are set to their defaults when SQL NULL is
     * returned from the <code>ResultSet</code>.  Numeric fields are set to 0
     * and booleans are set to false.  Object bean properties are set to 
     * <code>null</code> when SQL NULL is returned.  This is the same behavior
     * as the <code>ResultSet</code> get* methods.
     * </p>
     *
     * @param rs ResultSet that supplies the bean data
     * @param type Class from which to create the bean instance
     * @throws SQLException if a database access error occurs
     * @return the newly created List of beans
     */
    public List toBeanList(ResultSet rs, Class type) throws SQLException {
        List results = new ArrayList();

        if (!rs.next()) {
            return results;
        }

        PropertyDescriptor[] props = this.propertyDescriptors(type);
        ResultSetMetaData rsmd = rs.getMetaData();
        int[] columnToProperty = this.mapColumnsToProperties(rsmd, props);

        do {
            results.add(this.createBean(rs, type, props, columnToProperty));
        } while (rs.next());

        return results;
    }

    /**
     * Creates a new object and initializes its fields from the ResultSet.
     *
     * @param rs The result set.
     * @param type The bean type (the return type of the object).
     * @param props The property descriptors.
     * @param columnToProperty The column indices in the result set.
     * @return An initialized object.
     * @throws SQLException if a database error occurs.
     */
    private Object createBean(ResultSet rs, Class type, PropertyDescriptor[] props, int[] columnToProperty)
            throws SQLException {

        Object bean = this.newInstance(type);

        for (int i = 1; i < columnToProperty.length; i++) {

            if (columnToProperty[i] == PROPERTY_NOT_FOUND) {
                continue;
            }

            PropertyDescriptor prop = props[columnToProperty[i]];
            Class propType = prop.getPropertyType();

            Object value = this.processColumn(rs, i, propType);

            if (propType != null && value == null && propType.isPrimitive()) {
                value = primitiveDefaults.get(propType);
            }

            this.callSetter(bean, prop, value);
        }

        return bean;
    }

    /**
     * Calls the setter method on the target object for the given property.
     * If no setter method exists for the property, this method does nothing.
     * @param target The object to set the property on.
     * @param prop The property to set.
     * @param value The value to pass into the setter.
     * @throws SQLException if an error occurs setting the property.
     */
    private void callSetter(Object target, PropertyDescriptor prop, Object value) throws SQLException {

        Method setter = prop.getWriteMethod();

        if (setter == null) {
            return;
        }

        Class[] params = setter.getParameterTypes();
        try {
            // convert types for some popular ones
            if (value != null) {
                if (value instanceof java.util.Date) {
                    if (params[0].getName().equals("java.sql.Date")) {
                        value = new java.sql.Date(((java.util.Date) value).getTime());
                    } else if (params[0].getName().equals("java.sql.Time")) {
                        value = new java.sql.Time(((java.util.Date) value).getTime());
                    } else if (params[0].getName().equals("java.sql.Timestamp")) {
                        value = new java.sql.Timestamp(((java.util.Date) value).getTime());
                    }
                }
            }

            // Don't call setter if the value object isn't the right type 
            if (this.isCompatibleType(value, params[0])) {
                setter.invoke(target, new Object[] { value });
            } else {
                throw new SQLException("Cannot set " + prop.getName() + ": incompatible types.");
            }

        } catch (IllegalArgumentException e) {
            throw new SQLException("Cannot set " + prop.getName() + ": " + e.getMessage());

        } catch (IllegalAccessException e) {
            throw new SQLException("Cannot set " + prop.getName() + ": " + e.getMessage());

        } catch (InvocationTargetException e) {
            throw new SQLException("Cannot set " + prop.getName() + ": " + e.getMessage());
        }
    }

    /**
     * ResultSet.getObject() returns an Integer object for an INT column.  The
     * setter method for the property might take an Integer or a primitive int.
     * This method returns true if the value can be successfully passed into
     * the setter method.  Remember, Method.invoke() handles the unwrapping
     * of Integer into an int.
     * 
     * @param value The value to be passed into the setter method.
     * @param type The setter's parameter type.
     * @return boolean True if the value is compatible.
     */
    private boolean isCompatibleType(Object value, Class type) {
        // Do object check first, then primitives
        if (value == null || type.isInstance(value)) {
            return true;

        } else if (type.equals(Integer.TYPE) && Integer.class.isInstance(value)) {
            return true;

        } else if (type.equals(Long.TYPE) && Long.class.isInstance(value)) {
            return true;

        } else if (type.equals(Double.TYPE) && Double.class.isInstance(value)) {
            return true;

        } else if (type.equals(Float.TYPE) && Float.class.isInstance(value)) {
            return true;

        } else if (type.equals(Short.TYPE) && Short.class.isInstance(value)) {
            return true;

        } else if (type.equals(Byte.TYPE) && Byte.class.isInstance(value)) {
            return true;

        } else if (type.equals(Character.TYPE) && Character.class.isInstance(value)) {
            return true;

        } else if (type.equals(Boolean.TYPE) && Boolean.class.isInstance(value)) {
            return true;

        } else {
            return false;
        }

    }

    /**
     * Factory method that returns a new instance of the given Class.  This
     * is called at the start of the bean creation process and may be 
     * overridden to provide custom behavior like returning a cached bean
     * instance.
     *
     * @param c The Class to create an object from.
     * @return A newly created object of the Class.
     * @throws SQLException if creation failed.
     */
    protected Object newInstance(Class c) throws SQLException {
        try {
            return c.newInstance();

        } catch (InstantiationException e) {
            throw new SQLException("Cannot create " + c.getName() + ": " + e.getMessage());

        } catch (IllegalAccessException e) {
            throw new SQLException("Cannot create " + c.getName() + ": " + e.getMessage());
        }
    }

    /**
     * Returns a PropertyDescriptor[] for the given Class.
     *
     * @param c The Class to retrieve PropertyDescriptors for.
     * @return A PropertyDescriptor[] describing the Class.
     * @throws SQLException if introspection failed.
     */
    private PropertyDescriptor[] propertyDescriptors(Class c) throws SQLException {
        // Introspector caches BeanInfo classes for better performance
        BeanInfo beanInfo = null;
        try {
            beanInfo = Introspector.getBeanInfo(c);

        } catch (IntrospectionException e) {
            throw new SQLException("Bean introspection failed: " + e.getMessage());
        }

        return beanInfo.getPropertyDescriptors();
    }

    /**
     * The positions in the returned array represent column numbers.  The 
     * values stored at each position represent the index in the 
     * <code>PropertyDescriptor[]</code> for the bean property that matches 
     * the column name.  If no bean property was found for a column, the 
     * position is set to <code>PROPERTY_NOT_FOUND</code>.
     * 
     * @param rsmd The <code>ResultSetMetaData</code> containing column 
     * information.
     * 
     * @param props The bean property descriptors.
     * 
     * @throws SQLException if a database access error occurs
     *
     * @return An int[] with column index to property index mappings.  The 0th 
     * element is meaningless because JDBC column indexing starts at 1.
     */
    protected int[] mapColumnsToProperties(ResultSetMetaData rsmd, PropertyDescriptor[] props) throws SQLException {

        int cols = rsmd.getColumnCount();
        int columnToProperty[] = new int[cols + 1];
        Arrays.fill(columnToProperty, PROPERTY_NOT_FOUND);

        for (int col = 1; col <= cols; col++) {
            String columnName = rsmd.getColumnName(col);
            for (int i = 0; i < props.length; i++) {

                if (columnName.equalsIgnoreCase(props[i].getName())) {
                    columnToProperty[col] = i;
                    break;
                }
            }
        }

        return columnToProperty;
    }

    /**
     * Convert a <code>ResultSet</code> column into an object.  Simple 
     * implementations could just call <code>rs.getObject(index)</code> while
     * more complex implementations could perform type manipulation to match 
     * the column's type to the bean property type.
     * 
     * <p>
     * This implementation calls the appropriate <code>ResultSet</code> getter 
     * method for the given property type to perform the type conversion.  If 
     * the property type doesn't match one of the supported 
     * <code>ResultSet</code> types, <code>getObject</code> is called.
     * </p>
     * 
     * @param rs The <code>ResultSet</code> currently being processed.  It is
     * positioned on a valid row before being passed into this method.
     * 
     * @param index The current column index being processed.
     * 
     * @param propType The bean property type that this column needs to be
     * converted into.
     * 
     * @throws SQLException if a database access error occurs
     * 
     * @return The object from the <code>ResultSet</code> at the given column
     * index after optional type processing or <code>null</code> if the column
     * value was SQL NULL.
     */
    protected Object processColumn(ResultSet rs, int index, Class propType) throws SQLException {

        if (!propType.isPrimitive() && rs.getObject(index) == null) {
            return null;
        }

        if (propType.equals(String.class)) {
            return rs.getString(index);

        } else if (propType.equals(Integer.TYPE) || propType.equals(Integer.class)) {
            return new Integer(rs.getInt(index));

        } else if (propType.equals(Boolean.TYPE) || propType.equals(Boolean.class)) {
            return new Boolean(rs.getBoolean(index));

        } else if (propType.equals(Long.TYPE) || propType.equals(Long.class)) {
            return new Long(rs.getLong(index));

        } else if (propType.equals(Double.TYPE) || propType.equals(Double.class)) {
            return new Double(rs.getDouble(index));

        } else if (propType.equals(Float.TYPE) || propType.equals(Float.class)) {
            return new Float(rs.getFloat(index));

        } else if (propType.equals(Short.TYPE) || propType.equals(Short.class)) {
            return new Short(rs.getShort(index));

        } else if (propType.equals(Byte.TYPE) || propType.equals(Byte.class)) {
            return new Byte(rs.getByte(index));

        } else if (propType.equals(Timestamp.class)) {
            return rs.getTimestamp(index);

        } else {
            return rs.getObject(index);
        }

    }

}