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 */
017package org.apache.commons.beanutils.converters;
018
019/**
020 * {@link org.apache.commons.beanutils.Converter} implementation that handles conversion
021 * to and from <strong>java.lang.Character</strong> objects.
022 * <p>
023 * Can be configured to either return a <em>default value</em> or throw a
024 * <code>ConversionException</code> if a conversion error occurs.
025 *
026 * @since 1.3
027 */
028public final class CharacterConverter extends AbstractConverter {
029
030    /**
031     * Construct a <strong>java.lang.Character</strong> <em>Converter</em> that throws
032     * a <code>ConversionException</code> if an error occurs.
033     */
034    public CharacterConverter() {
035    }
036
037    /**
038     * Construct a <strong>java.lang.Character</strong> <em>Converter</em> that returns
039     * a default value if an error occurs.
040     *
041     * @param defaultValue The default value to be returned
042     * if the value to be converted is missing or an error
043     * occurs converting the value.
044     */
045    public CharacterConverter(final Object defaultValue) {
046        super(defaultValue);
047    }
048
049    /**
050     * <p>Convert a java.lang.Class or object into a String.</p>
051     *
052     * @param value The input value to be converted
053     * @return the converted String value.
054     * @since 1.8.0
055     */
056    @Override
057    protected String convertToString(final Object value) {
058        final String strValue = value.toString();
059        return strValue.length() == 0 ? "" : strValue.substring(0, 1);
060    }
061
062    /**
063     * <p>Convert the input object into a java.lang.Character.</p>
064     *
065     * @param <T> Target type of the conversion.
066     * @param type Data type to which this value should be converted.
067     * @param value The input value to be converted.
068     * @return The converted value.
069     * @throws Exception if conversion cannot be performed successfully
070     * @since 1.8.0
071     */
072    @Override
073    protected <T> T convertToType(final Class<T> type, final Object value) throws Exception {
074        if (Character.class.equals(type) || Character.TYPE.equals(type)) {
075            return type.cast(Character.valueOf(value.toString().charAt(0)));
076        }
077
078        throw conversionException(type, value);
079    }
080
081    /**
082     * Return the default type this <code>Converter</code> handles.
083     *
084     * @return The default type this <code>Converter</code> handles.
085     * @since 1.8.0
086     */
087    @Override
088    protected Class<?> getDefaultType() {
089        return Character.class;
090    }
091
092}