    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one
    003 * or more contributor license agreements. See the NOTICE file
    004 * distributed with this work for additional information
    005 * regarding copyright ownership. The ASF licenses this file
    006 * to you under the Apache License, Version 2.0 (the
    007 * "License"); you may not use this file except in compliance
    008 * with the License. You may obtain a copy of the License at
    009 *
    010 * http://www.apache.org/licenses/LICENSE-2.0
    011 *
    012 * Unless required by applicable law or agreed to in writing,
    013 * software distributed under the License is distributed on an
    014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    015 * KIND, either express or implied. See the License for the
    016 * specific language governing permissions and limitations
    017 * under the License.
    018 */
    019package org.apache.commons.beanutils2.converters;
    020
    021import java.util.regex.Pattern;
    022
    023/**
    024 * {@link org.apache.commons.beanutils2.Converter} implementation that handles conversion to and from {@link Pattern}.
    025 *
    026 * @since 2.0.0
    027 */
    028public class PatternConverter extends AbstractConverter<Pattern> {
    029
    030    /**
    031     * Construct a <strong>{@link Pattern}</strong> <em>Converter</em> that throws a {@code ConversionException} if an error occurs.
    032     */
    033    public PatternConverter() {
    034    }
    035
    036    /**
    037     * Constructs a {@link org.apache.commons.beanutils2.Converter} that will return the specified default value if a conversion error occurs.
    038     *
    039     * @param defaultValue The default value to be returned if the value to be converted is missing or an error occurs converting the value.
    040     */
    041    public PatternConverter(final Pattern defaultValue) {
    042        super(defaultValue);
    043    }
    044
    045    /**
    046     * Converts the specified input object into an output object of the specified type.
    047     *
    048     * @param type  Data type to which this value should be converted.
    049     * @param value The String property value to convert.
    050     * @return A {@link Pattern} which represents the compiled configuration property.
    051     * @throws NullPointerException                   If the value is null.
    052     * @throws java.util.regex.PatternSyntaxException If the regular expression {@link String} provided is malformed.
    053     */
    054    @Override
    055    protected <T> T convertToType(final Class<T> type, final Object value) throws Throwable {
    056        if (Pattern.class.isAssignableFrom(type)) {
    057            final String stringValue = toString(value);
    058            return type.cast(Pattern.compile(stringValue));
    059        }
    060
    061        throw conversionException(type, value);
    062    }
    063
    064    /**
    065     * Gets the default type this {@code Converter} handles.
    066     *
    067     * @return The default type this {@code Converter} handles.
    068     * @since 2.0.0
    069     */
    070    @Override
    071    protected Class<Pattern> getDefaultType() {
    072        return Pattern.class;
    073    }
    074}