/*
* 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.
*/
package org.apache.commons.beanutils;
import java.sql.SQLException;
import java.util.Iterator;
import java.util.NoSuchElementException;
/**
* <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: 556221 $ $Date: 2007-07-14 05:19:21 +0100 (Sat, 14 Jul 2007) $
*/
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
* @return <code>true<code> if the mapped property contains a value for
* the specified key, otherwise <code>false</code>
*
* @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
* @return The property's value
*
* @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.getObjectFromResultSet(name);
} catch (SQLException e) {
throw new RuntimeException
("get(" + name + "): SQLException: " + e);
}
}
/**
* 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
* @return The indexed property's value
*
* @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
* @return The mapped property's value
*
* @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.
*
* @return The associated DynaClass
*/
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>
*
* @return <code>true</code> if the result set has another
* row, otherwise <code>false</code>
*/
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>
*
* @return advance to the new row and return this
*/
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;
}
}
}
}