| // *************************************************************************************************************************** |
| // * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file * |
| // * distributed with this work for additional information regarding copyright ownership. The ASF licenses this file * |
| // * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance * |
| // * with the License. You may obtain a copy of the License at * |
| // * * |
| // * http://www.apache.org/licenses/LICENSE-2.0 * |
| // * * |
| // * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an * |
| // * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the * |
| // * specific language governing permissions and limitations under the License. * |
| // *************************************************************************************************************************** |
| package org.apache.juneau.config.vars; |
| |
| import org.apache.juneau.config.*; |
| import org.apache.juneau.svl.*; |
| |
| /** |
| * Config file variable resolver. |
| * |
| * <p> |
| * The format for this var is <js>"$C{key[,defaultValue]}"</js>. |
| * See {@link Config#getString(String)} for the format of the key. |
| * |
| * <p> |
| * This variable resolver requires that a {@link Config} object be set as a context object on the resolver or a |
| * session object on the resolver session. |
| * |
| * <h5 class='section'>Example:</h5> |
| * <p class='bcode w800'> |
| * <jc>// Create a config object.</jc> |
| * Config config = Config.<jsm>create</jsm>().name(<js>"MyConfig.cfg"</js>).build(); |
| * |
| * <jc>// Create a variable resolver that resolves config file entries (e.g. "$C{MySection/myKey}")</jc> |
| * VarResolver r = <jk>new</jk> VarResolver().addVars(ConfigVar.<js>class</js>) |
| * .addContextObject(<jsf>SESSION_config</jsf>, configFile); |
| * |
| * <jc>// Use it!</jc> |
| * System.<jsf>out</jsf>.println(r.resolve(<js>"Value for myKey in section MySection is $C{MySection/myKey}"</js>)); |
| * </p> |
| * |
| * <p> |
| * Since this is a {@link SimpleVar}, any variables contained in the result will be recursively resolved. |
| * Likewise, if the arguments contain any variables, those will be resolved before they are passed to this var. |
| * |
| * <ul class='seealso'> |
| * <li class='link'>{@doc juneau-marshall.SimpleVariableLanguage.VarResolvers} |
| * <li class='link'>{@doc juneau-config.Variables} |
| * </ul> |
| */ |
| public class ConfigVar extends DefaultingVar { |
| |
| /** |
| * The name of the session or context object that identifies the {@link Config} object. |
| */ |
| public static final String SESSION_config = "config"; |
| |
| /** The name of this variable. */ |
| public static final String NAME = "C"; |
| |
| /** |
| * Constructor. |
| */ |
| public ConfigVar() { |
| super(NAME); |
| } |
| |
| @Override /* Var */ |
| public String resolve(VarResolverSession session, String key) { |
| return session.getSessionObject(Config.class, SESSION_config, true).getString(key); |
| } |
| } |