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
021import org.apache.juneau.reflect.*;
022
023/**
024 * Configurable properties on the {@link VarResolver} class.
025 *
026 * <p>
027 * Used to associate {@link Var Vars} and context objects with {@link VarResolver VarResolvers}.
028 *
029 * <ul class='seealso'>
030 *    <li class='link'>{@doc juneau-svl.VarResolvers}
031 * </ul>
032 */
033public class VarResolverContext {
034
035   private final Class<?>[] vars;
036   private final Map<String,Var> varMap;
037   private final Map<String,Object> contextObjects;
038
039   /**
040    * Constructor.
041    *
042    * @param vars The Var classes used for resolving string variables.
043    * @param contextObjects Read-only context objects.
044    */
045   public VarResolverContext(Class<? extends Var>[] vars, Map<String,Object> contextObjects) {
046
047      this.vars = Arrays.copyOf(vars, vars.length);
048
049      Map<String,Var> m = new ConcurrentSkipListMap<>();
050      for (Class<?> c : vars) {
051         ClassInfo ci = ClassInfo.of(c);
052         if (! ci.isChildOf(Var.class))
053            throw new VarResolverException("Invalid variable class ''{0}''.  Must extend from Var.", ci);
054         Var v = castOrCreate(Var.class, c);
055         m.put(v.getName(), v);
056      }
057
058      this.varMap = unmodifiableMap(m);
059      this.contextObjects = immutableMap(contextObjects);
060   }
061
062   /**
063    * Returns an unmodifiable map of {@link Var Vars} associated with this context.
064    *
065    * @return A map whose keys are var names (e.g. <js>"S"</js>) and values are {@link Var} instances.
066    */
067   protected Map<String,Var> getVarMap() {
068      return varMap;
069   }
070
071   /**
072    * Returns an array of variables define in this variable resolver context.
073    *
074    * @return A new array containing the variables in this context.
075    */
076   protected Class<?>[] getVars() {
077      return Arrays.copyOf(vars, vars.length);
078   }
079
080   /**
081    * Returns the context object with the specified name.
082    *
083    * @param name The name of the context object.
084    * @return The context object, or <jk>null</jk> if no context object is specified with that name.
085    */
086   protected Object getContextObject(String name) {
087      return contextObjects == null ? null : contextObjects.get(name);
088   }
089
090   /**
091    * Returns the context map of this variable resolver context.
092    *
093    * @return An unmodifiable map of the context objects of this variable resolver context.
094    */
095   protected Map<String,Object> getContextObjects() {
096      return contextObjects;
097   }
098}