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
018
019package org.apache.commons.beanutils.converters;
020
021
022import java.util.List;
023import org.apache.commons.beanutils.ConversionException;
024
025
026/**
027 * Standard {@link org.apache.commons.beanutils.Converter} implementation that converts an incoming
028 * String into an array of String objects. On a conversion failure, returns
029 * a specified default value or throws a {@link ConversionException} depending
030 * on how this instance is constructed.
031 * <p>
032 * There is also some special handling where the input is of type int[].
033 * See method convert for more details.
034 *
035 * @version $Id$
036 * @since 1.4
037 * @deprecated Replaced by the new {@link ArrayConverter} implementation
038 */
039
040@Deprecated
041public final class StringArrayConverter extends AbstractArrayConverter {
042
043
044    // ----------------------------------------------------------- Constructors
045
046
047    /**
048     * Create a {@link org.apache.commons.beanutils.Converter} that will throw
049     * a {@link ConversionException} if a conversion error occurs.
050     */
051    public StringArrayConverter() {
052
053        this.defaultValue = null;
054        this.useDefault = false;
055
056    }
057
058
059    /**
060     * Create a {@link org.apache.commons.beanutils.Converter} that will return
061     * the specified default value if a conversion error occurs.
062     *
063     * @param defaultValue The default value to be returned
064     */
065    public StringArrayConverter(final Object defaultValue) {
066
067        this.defaultValue = defaultValue;
068        this.useDefault = true;
069
070    }
071
072
073    // ------------------------------------------------------- Static Variables
074
075
076    /**
077     * <p>Model object for type comparisons.</p>
078     */
079    private static final String[] MODEL = new String[0];
080
081    /**
082     * <p> Model object for int arrays.</p>
083     */
084    private static final int[] INT_MODEL = new int[0];
085
086
087
088    // --------------------------------------------------------- Public Methods
089
090
091    /**
092     * Convert the specified input object into an output object of the
093     * specified type.
094     * <p>
095     * If the value is already of type String[] then it is simply returned
096     * unaltered.
097     * <p>
098     * If the value is of type int[], then a String[] is returned where each
099     * element in the string array is the result of calling Integer.toString
100     * on the corresponding element of the int array. This was added as a
101     * result of bugzilla request #18297 though there is not complete
102     * agreement that this feature should have been added.
103     * <p>
104     * In all other cases, this method calls toString on the input object, then
105     * assumes the result is a comma-separated list of values. The values are
106     * split apart into the individual items and returned as the elements of an
107     * array. See class AbstractArrayConverter for the exact input formats
108     * supported.
109     *
110     * @param type is the data type to which this value should be converted.
111     * It is expected to be the class for type String[] (though this parameter
112     * is actually ignored by this method).
113     *
114     * @param value is the input value to be converted. If null then the
115     * default value is returned or an exception thrown if no default value
116     * exists.
117     * @return the converted value
118     *
119     * @throws ConversionException if conversion cannot be performed
120     * successfully, or the input is null and there is no default value set
121     * for this object.
122     */
123    @Override
124    public Object convert(final Class type, final Object value) {
125
126        // Deal with a null value
127        if (value == null) {
128            if (useDefault) {
129                return (defaultValue);
130            } else {
131                throw new ConversionException("No value specified");
132            }
133        }
134
135        // Deal with the no-conversion-needed case
136        if (MODEL.getClass() == value.getClass()) {
137            return (value);
138        }
139
140        // Deal with the input value as an int array
141        if (INT_MODEL.getClass() == value.getClass())
142        {
143            final int[] values = (int[]) value;
144            final String[] results = new String[values.length];
145            for (int i = 0; i < values.length; i++)
146            {
147                results[i] = Integer.toString(values[i]);
148            }
149
150            return (results);
151        }
152
153        // Parse the input value as a String into elements
154        // and convert to the appropriate type
155        try {
156            final List list = parseElements(value.toString());
157            final String[] results = new String[list.size()];
158            for (int i = 0; i < results.length; i++) {
159                results[i] = (String) list.get(i);
160            }
161            return (results);
162        } catch (final Exception e) {
163            if (useDefault) {
164                return (defaultValue);
165            } else {
166                throw new ConversionException(value.toString(), e);
167            }
168        }
169    }
170
171}