    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.configuration2.builder;
    018
    019import java.util.Map;
    020
    021/**
    022 * <p>
    023 * An interface to be implemented by objects which can be used to parameterize a
    024 * {@link ConfigurationBuilder}.
    025 * </p>
    026 * <p>
    027 * This interface is part of a Java DSL for creating and initializing builders
    028 * for specific {@code Configuration} classes. Concrete implementations
    029 * typically collect a set of related properties for the builder. There will be
    030 * specific set methods for providing values for these properties. Then, this
    031 * interface requires a generic {@code getParameters()} method which has to
    032 * return all property values as a map. When constructing the builder the map is
    033 * evaluated to define properties of the {@code Configuration} objects to be
    034 * constructed.
    035 * </p>
    036 *
    037 * @since 2.0
    038 */
    039public interface BuilderParameters
    040{
    041    /**
    042     * Constant for a prefix for reserved initialization parameter keys. If a
    043     * parameter was set whose key starts with this prefix, it is filtered out
    044     * before the initialization of a newly created result object. This
    045     * mechanism allows implementing classes to store specific configuration
    046     * data in the parameters map which does not represent a property value for
    047     * the result object.
    048     */
    049    String RESERVED_PARAMETER_PREFIX = "config-";
    050
    051    /**
    052     * Returns a map with all parameters defined by this objects. The keys of
    053     * the map correspond to concrete properties supported by the
    054     * {@code Configuration} implementation class the builder produces. The
    055     * values are the corresponding property values. The return value must not
    056     * be <b>null</b>.
    057     *
    058     * @return a map with builder parameters
    059     */
    060    Map<String, Object> getParameters();
    061}