    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017
    018package org.apache.commons.beanutils;
    019
    020import java.sql.SQLException;
    021import java.util.Iterator;
    022import java.util.NoSuchElementException;
    023
    024/**
    025 * <p>Implements {@link Iterator} returned by the
    026 * <code>iterator()</code> method of {@link ResultSetDynaClass}.  Each
    027 * object returned by this iterator will be a {@link DynaBean} that
    028 * represents a single row from the result set being wrapped.</p>
    029 *
    030 */
    031public class ResultSetIterator implements DynaBean, Iterator<DynaBean> {
    032
    033    /**
    034     * <p>Flag indicating whether the result set is currently positioned at a
    035     * row for which we have not yet returned an element in the iteration.</p>
    036     */
    037    protected boolean current;
    038
    039    /**
    040     * <p>The {@link ResultSetDynaClass} we are associated with.</p>
    041     */
    042    protected ResultSetDynaClass dynaClass;
    043
    044    /**
    045     * <p>Flag indicating whether the result set has indicated that there are
    046     * no further rows.</p>
    047     */
    048    protected boolean eof;
    049
    050    /**
    051     * <p>Construct an <code>Iterator</code> for the result set being wrapped
    052     * by the specified {@link ResultSetDynaClass}.</p>
    053     *
    054     * @param dynaClass The {@link ResultSetDynaClass} wrapping the
    055     *  result set we will iterate over
    056     */
    057    ResultSetIterator(final ResultSetDynaClass dynaClass) {
    058        this.dynaClass = dynaClass;
    059    }
    060
    061    /**
    062     * <p>Advance the result set to the next row, if there is not a current
    063     * row (and if we are not already at eof).</p>
    064     *
    065     * @throws SQLException if the result set throws an exception
    066     */
    067    protected void advance() throws SQLException {
    068        if (!current && !eof) {
    069            if (dynaClass.getResultSet().next()) {
    070                current = true;
    071                eof = false;
    072            } else {
    073                current = false;
    074                eof = true;
    075            }
    076        }
    077    }
    078
    079    /**
    080     * Does the specified mapped property contain a value for the specified
    081     * key value?
    082     *
    083     * @param name Name of the property to check
    084     * @param key Name of the key to check
    085     * @return <code>true</code> if the mapped property contains a value for
    086     * the specified key, otherwise <code>false</code>
    087     *
    088     * @throws IllegalArgumentException if there is no property
    089     *  of the specified name
    090     */
    091    @Override
    092    public boolean contains(final String name, final String key) {
    093        throw new UnsupportedOperationException
    094            ("FIXME - mapped properties not currently supported");
    095    }
    096
    097    /**
    098     * Return the value of a simple property with the specified name.
    099     *
    100     * @param name Name of the property whose value is to be retrieved
    101     * @return The property's value
    102     * @throws IllegalArgumentException if there is no property
    103     *  of the specified name
    104     */
    105    @Override
    106    public Object get(final String name) {
    107        if (dynaClass.getDynaProperty(name) == null) {
    108            throw new IllegalArgumentException(name);
    109        }
    110        try {
    111            return dynaClass.getObjectFromResultSet(name);
    112        } catch (final SQLException e) {
    113            throw new RuntimeException
    114                ("get(" + name + "): SQLException: " + e);
    115        }
    116    }
    117
    118    /**
    119     * Return the value of an indexed property with the specified name.
    120     *
    121     * @param name Name of the property whose value is to be retrieved
    122     * @param index Index of the value to be retrieved
    123     * @return The indexed property's value
    124     * @throws IllegalArgumentException if there is no property
    125     *  of the specified name
    126     * @throws IllegalArgumentException if the specified property
    127     *  exists, but is not indexed
    128     * @throws IndexOutOfBoundsException if the specified index
    129     *  is outside the range of the underlying property
    130     * @throws NullPointerException if no array or List has been
    131     *  initialized for this property
    132     */
    133    @Override
    134    public Object get(final String name, final int index) {
    135        throw new UnsupportedOperationException
    136            ("FIXME - indexed properties not currently supported");
    137    }
    138
    139    /**
    140     * Return the value of a mapped property with the specified name,
    141     * or <code>null</code> if there is no value for the specified key.
    142     *
    143     * @param name Name of the property whose value is to be retrieved
    144     * @param key Key of the value to be retrieved
    145     * @return The mapped property's value
    146     * @throws IllegalArgumentException if there is no property
    147     *  of the specified name
    148     * @throws IllegalArgumentException if the specified property
    149     *  exists, but is not mapped
    150     */
    151    @Override
    152    public Object get(final String name, final String key) {
    153        throw new UnsupportedOperationException
    154            ("FIXME - mapped properties not currently supported");
    155    }
    156
    157    /**
    158     * Return the <code>DynaClass</code> instance that describes the set of
    159     * properties available for this DynaBean.
    160     *
    161     * @return The associated DynaClass
    162     */
    163    @Override
    164    public DynaClass getDynaClass() {
    165        return this.dynaClass;
    166    }
    167
    168    /**
    169     * <p>Return <code>true</code> if the iteration has more elements.</p>
    170     *
    171     * @return <code>true</code> if the result set has another
    172     * row, otherwise <code>false</code>
    173     */
    174    @Override
    175    public boolean hasNext() {
    176        try {
    177            advance();
    178            return !eof;
    179        } catch (final SQLException e) {
    180            throw new RuntimeException("hasNext():  SQLException:  " + e);
    181        }
    182    }
    183
    184    /**
    185     * <p>Return the next element in the iteration.</p>
    186     *
    187     * @return advance to the new row and return this
    188     */
    189    @Override
    190    public DynaBean next() {
    191        try {
    192            advance();
    193            if (eof) {
    194                throw new NoSuchElementException();
    195            }
    196            current = false;
    197            return this;
    198        } catch (final SQLException e) {
    199            throw new RuntimeException("next():  SQLException:  " + e);
    200        }
    201
    202    }
    203
    204    /**
    205     * <p>Remove the current element from the iteration.  This method is
    206     * not supported.</p>
    207     */
    208    @Override
    209    public void remove() {
    210        throw new UnsupportedOperationException("remove()");
    211    }
    212
    213    /**
    214     * Remove any existing value for the specified key on the
    215     * specified mapped property.
    216     *
    217     * @param name Name of the property for which a value is to
    218     *  be removed
    219     * @param key Key of the value to be removed
    220     * @throws IllegalArgumentException if there is no property
    221     *  of the specified name
    222     */
    223    @Override
    224    public void remove(final String name, final String key) {
    225        throw new UnsupportedOperationException
    226            ("FIXME - mapped operations not currently supported");
    227    }
    228
    229    /**
    230     * Set the value of an indexed property with the specified name.
    231     *
    232     * @param name Name of the property whose value is to be set
    233     * @param index Index of the property to be set
    234     * @param value Value to which this property is to be set
    235     * @throws ConversionException if the specified value cannot be
    236     *  converted to the type required for this property
    237     * @throws IllegalArgumentException if there is no property
    238     *  of the specified name
    239     * @throws IllegalArgumentException if the specified property
    240     *  exists, but is not indexed
    241     * @throws IndexOutOfBoundsException if the specified index
    242     *  is outside the range of the underlying property
    243     */
    244    @Override
    245    public void set(final String name, final int index, final Object value) {
    246        throw new UnsupportedOperationException
    247            ("FIXME - indexed properties not currently supported");
    248    }
    249
    250    /**
    251     * Set the value of a simple property with the specified name.
    252     *
    253     * @param name Name of the property whose value is to be set
    254     * @param value Value to which this property is to be set
    255     * @throws ConversionException if the specified value cannot be
    256     *  converted to the type required for this property
    257     * @throws IllegalArgumentException if there is no property
    258     *  of the specified name
    259     * @throws NullPointerException if an attempt is made to set a
    260     *  primitive property to null
    261     */
    262    @Override
    263    public void set(final String name, final Object value) {
    264        if (dynaClass.getDynaProperty(name) == null) {
    265            throw new IllegalArgumentException(name);
    266        }
    267        try {
    268            dynaClass.getResultSet().updateObject(name, value);
    269        } catch (final SQLException e) {
    270            throw new RuntimeException
    271                ("set(" + name + "): SQLException: " + e);
    272        }
    273    }
    274
    275    /**
    276     * Set the value of a mapped property with the specified name.
    277     *
    278     * @param name Name of the property whose value is to be set
    279     * @param key Key of the property to be set
    280     * @param value Value to which this property is to be set
    281     * @throws ConversionException if the specified value cannot be
    282     *  converted to the type required for this property
    283     * @throws IllegalArgumentException if there is no property
    284     *  of the specified name
    285     * @throws IllegalArgumentException if the specified property
    286     *  exists, but is not mapped
    287     */
    288    @Override
    289    public void set(final String name, final String key, final Object value) {
    290        throw new UnsupportedOperationException
    291            ("FIXME - mapped properties not currently supported");
    292    }
    293
    294}