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