001// ***************************************************************************************************************************
002// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file *
003// * distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file        *
004// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance            *
005// * with the License.  You may obtain a copy of the License at                                                              *
006// *                                                                                                                         *
007// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
008// *                                                                                                                         *
009// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an  *
010// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the        *
011// * specific language governing permissions and limitations under the License.                                              *
012// ***************************************************************************************************************************
013package org.apache.juneau.svl;
014
015import static org.apache.juneau.internal.ClassUtils.*;
016import static org.apache.juneau.internal.CollectionUtils.*;
017
018import java.util.*;
019import java.util.concurrent.*;
020
021/**
022 * Configurable properties on the {@link VarResolver} class.
023 * 
024 * <p>
025 * Used to associate {@link Var Vars} and context objects with {@link VarResolver VarResolvers}.
026 * 
027 * <h5 class='section'>See Also:</h5>
028 * <ul>
029 *    <li class='link'><a class="doclink" href="../../../../overview-summary.html#juneau-svl.VarResolvers">Overview &gt; juneau-svl &gt; VarResolvers and VarResolverSessions</a>
030 * </ul>
031 */
032public class VarResolverContext {
033
034   private final Class<?>[] vars;
035   private final Map<String,Var> varMap;
036   private final Map<String,Object> contextObjects;
037
038   /**
039    * Constructor.
040    * 
041    * @param vars The Var classes used for resolving string variables.
042    * @param contextObjects Read-only context objects.
043    */
044   public VarResolverContext(Class<? extends Var>[] vars, Map<String,Object> contextObjects) {
045
046      this.vars = Arrays.copyOf(vars, vars.length);
047
048      Map<String,Var> m = new ConcurrentSkipListMap<>();
049      for (Class<?> c : vars) {
050         if (! isParentClass(Var.class, c))
051            throw new RuntimeException("Invalid variable class.  Must extend from Var");
052         Var v = newInstance(Var.class, c);
053         m.put(v.getName(), v);
054      }
055
056      this.varMap = unmodifiableMap(m);
057      this.contextObjects = immutableMap(contextObjects);
058   }
059
060   /**
061    * Returns an unmodifiable map of {@link Var Vars} associated with this context.
062    * 
063    * @return A map whose keys are var names (e.g. <js>"S"</js>) and values are {@link Var} instances.
064    */
065   protected Map<String,Var> getVarMap() {
066      return varMap;
067   }
068
069   /**
070    * Returns an array of variables define in this variable resolver context.
071    * 
072    * @return A new array containing the variables in this context.
073    */
074   protected Class<?>[] getVars() {
075      return Arrays.copyOf(vars, vars.length);
076   }
077
078   /**
079    * Returns the context object with the specified name.
080    * 
081    * @param name The name of the context object.
082    * @return The context object, or <jk>null</jk> if no context object is specified with that name.
083    */
084   protected Object getContextObject(String name) {
085      return contextObjects == null ? null : contextObjects.get(name);
086   }
087
088   /**
089    * Returns the context map of this variable resolver context.
090    * 
091    * @return An unmodifiable map of the context objects of this variable resolver context.
092    */
093   protected Map<String,Object> getContextObjects() {
094      return contextObjects;
095   }
096}