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 java.util.*;
017import java.util.concurrent.*;
018
019import org.apache.juneau.collections.*;
020import org.apache.juneau.reflect.*;
021
022/**
023 * Configurable properties on the {@link VarResolver} class.
024 *
025 * <p>
026 * Used to associate {@link Var Vars} and context objects with {@link VarResolver VarResolvers}.
027 *
028 * <ul class='seealso'>
029 *    <li class='link'>{@doc VarResolvers}
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         ClassInfo ci = ClassInfo.of(c);
051         if (! ci.isChildOf(Var.class))
052            throw new VarResolverException("Invalid variable class ''{0}''.  Must extend from Var.", ci);
053         Var v = castOrCreate(Var.class, c);
054         m.put(v.getName(), v);
055      }
056
057      this.varMap = AMap.unmodifiable(m);
058      this.contextObjects = AMap.unmodifiable(contextObjects);
059   }
060
061   /**
062    * Returns an unmodifiable map of {@link Var Vars} associated with this context.
063    *
064    * @return A map whose keys are var names (e.g. <js>"S"</js>) and values are {@link Var} instances.
065    */
066   protected Map<String,Var> getVarMap() {
067      return varMap;
068   }
069
070   /**
071    * Returns an array of variables define in this variable resolver context.
072    *
073    * @return A new array containing the variables in this context.
074    */
075   protected Class<?>[] getVars() {
076      return Arrays.copyOf(vars, vars.length);
077   }
078
079   /**
080    * Returns the context object with the specified name.
081    *
082    * @param name The name of the context object.
083    * @return The context object, or <jk>null</jk> if no context object is specified with that name.
084    */
085   protected Object getContextObject(String name) {
086      return contextObjects == null ? null : contextObjects.get(name);
087   }
088
089   /**
090    * Returns the context map of this variable resolver context.
091    *
092    * @return An unmodifiable map of the context objects of this variable resolver context.
093    */
094   protected Map<String,Object> getContextObjects() {
095      return contextObjects;
096   }
097}