    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 *     https://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.configuration2.builder.combined;
    018
    019import java.util.Set;
    020
    021import org.apache.commons.configuration2.HierarchicalConfiguration;
    022import org.apache.commons.configuration2.beanutils.XMLBeanDeclaration;
    023
    024/**
    025 * <p>
    026 * A specialized {@code BeanDeclaration} implementation that represents the declaration of a configuration source.
    027 * </p>
    028 * <p>
    029 * Instances of this class are able to extract all information about a configuration source from the configuration
    030 * definition file. The declaration of a configuration source is very similar to a bean declaration processed by
    031 * {@code XMLBeanDeclaration}. There are very few differences, for example some reserved attributes like {@code optional} and
    032 * {@code at}, and the fact that a bean factory is never needed.
    033 * </p>
    034 *
    035 * @since 2.0
    036 */
    037public class ConfigurationDeclaration extends XMLBeanDeclaration {
    038
    039    /** Stores a reference to the associated configuration builder. */
    040    private final CombinedConfigurationBuilder configurationBuilder;
    041
    042    /**
    043     * Creates a new instance of {@code ConfigurationDeclaration} and initializes it.
    044     *
    045     * @param builder the associated configuration builder
    046     * @param config the configuration this declaration is based onto
    047     */
    048    public ConfigurationDeclaration(final CombinedConfigurationBuilder builder, final HierarchicalConfiguration<?> config) {
    049        super(config);
    050        configurationBuilder = builder;
    051    }
    052
    053    /**
    054     * Gets the value of the {@code at} attribute.
    055     *
    056     * @return the value of the {@code at} attribute (can be <strong>null</strong>)
    057     */
    058    public String getAt() {
    059        final String result = getConfiguration().getString(CombinedConfigurationBuilder.ATTR_AT_RES);
    060        return result == null ? getConfiguration().getString(CombinedConfigurationBuilder.ATTR_AT) : result;
    061    }
    062
    063    /**
    064     * Gets the bean's class name. This implementation will always return <strong>null</strong>.
    065     *
    066     * @return the name of the bean's class
    067     */
    068    @Override
    069    public String getBeanClassName() {
    070        return null;
    071    }
    072
    073    /**
    074     * Gets the name of the bean factory. For configuration source declarations always a reserved factory is used. This
    075     * factory's name is returned by this implementation.
    076     *
    077     * @return the name of the bean factory
    078     */
    079    @Override
    080    public String getBeanFactoryName() {
    081        return CombinedConfigurationBuilder.CONFIG_BEAN_FACTORY_NAME;
    082    }
    083
    084    /**
    085     * Gets the associated configuration builder.
    086     *
    087     * @return the configuration builder
    088     */
    089    public CombinedConfigurationBuilder getConfigurationBuilder() {
    090        return configurationBuilder;
    091    }
    092
    093    /**
    094     * Gets the name for the represented configuration source. The name is optional, so this method can return
    095     * <strong>null</strong>.
    096     *
    097     * @return the name of the associated configuration source or <strong>null</strong>
    098     */
    099    public String getName() {
    100        return getConfiguration().getString(CombinedConfigurationBuilder.ATTR_NAME);
    101    }
    102
    103    /**
    104     * Gets a flag whether this configuration should always be created and added to the resulting combined configuration.
    105     * This flag is evaluated only for optional configurations whose normal creation has caused an error. If for such a
    106     * configuration the {@code forceCreate} attribute is set and the corresponding configuration provider supports this
    107     * mode, an empty configuration will be created and added to the resulting combined configuration.
    108     *
    109     * @return the value of the {@code forceCreate} attribute
    110     */
    111    public boolean isForceCreate() {
    112        return getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_FORCECREATE, false);
    113    }
    114
    115    /**
    116     * Gets a flag whether this is an optional configuration.
    117     *
    118     * @return a flag if this declaration points to an optional configuration
    119     */
    120    public boolean isOptional() {
    121        Boolean value = getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_OPTIONAL_RES, null);
    122        if (value == null) {
    123            value = getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_OPTIONAL, Boolean.FALSE);
    124        }
    125        return value.booleanValue();
    126    }
    127
    128    /**
    129     * Returns a flag whether a builder with reloading support should be created. This may not be supported by all
    130     * configuration builder providers.
    131     *
    132     * @return a flag whether a reloading builder should be created
    133     */
    134    public boolean isReload() {
    135        return getConfiguration().getBoolean(CombinedConfigurationBuilder.ATTR_RELOAD, false);
    136    }
    137
    138    /**
    139     * {@inheritDoc} This implementation checks for additional reserved attribute names. Note that in some cases the
    140     * presence of other attribute names determine whether a name is reserved or not. For instance, per default the
    141     * attribute {@code config-at} is reserved. However, if this attribute is not present, the attribute {@code at} is also
    142     * considered as a reserved attribute. (This is mainly done for dealing with legacy configuration files supported by
    143     * earlier versions of this library.)
    144     */
    145    @Override
    146    protected boolean isReservedAttributeName(final String name) {
    147        if (super.isReservedAttributeName(name)) {
    148            return true;
    149        }
    150
    151        final Set<String> attributes = getAttributeNames();
    152        return CombinedConfigurationBuilder.ATTR_ATNAME.equals(name) && !attributes.contains(RESERVED_PREFIX + CombinedConfigurationBuilder.ATTR_ATNAME)
    153            || CombinedConfigurationBuilder.ATTR_OPTIONALNAME.equals(name)
    154                && !attributes.contains(RESERVED_PREFIX + CombinedConfigurationBuilder.ATTR_OPTIONALNAME);
    155    }
    156}