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.rest.vars;
014
015import java.util.*;
016
017import org.apache.juneau.cp.*;
018import org.apache.juneau.http.response.*;
019import org.apache.juneau.rest.*;
020import org.apache.juneau.svl.*;
021
022/**
023 * Localized string variable resolver.
024 *
025 * <p>
026 * The format for this var is <js>"$L{key[,args...]}"</js>.
027 *
028 * <p>
029 * This variable resolver requires that a {@link RestRequest} bean be available in the session bean store.
030 *
031 * <p>
032 * Values are pulled from the {@link RestRequest#getMessage(String,Object[])} method.
033 * These in turn are pulled from the resource bundle associated with the servlet class where the request was made.
034 *
035 * <p>
036 * Since this is a {@link SimpleVar}, any variables contained in the result will be recursively resolved.
037 * Likewise, if the arguments contain any variables, those will be resolved before they are passed to this var.
038 *
039 * <h5 class='section'>See Also:</h5><ul>
040 *    <li class='link'><a class="doclink" href="../../../../../index.html#jm.SvlVariables">SVL Variables</a>
041 * </ul>
042 */
043public class LocalizationVar extends MultipartVar {
044
045   /** The name of this variable. */
046   public static final String NAME = "L";
047
048   /**
049    * Constructor.
050    */
051   public LocalizationVar() {
052      super(NAME);
053   }
054
055   @Override /* Var */
056   public String resolve(VarResolverSession session, String[] args) {
057      if (args.length > 0) {
058         String key = args[0];
059         String[] a = (args.length > 1) ? Arrays.copyOfRange(args, 1, args.length) : new String[0];
060         Messages messages = null;
061         if (session.getBean(RestRequest.class).isPresent())
062            messages = session.getBean(RestRequest.class).get().getMessages();
063         if (messages == null)
064            messages = session.getBean(Messages.class).orElseThrow(InternalServerError::new);
065         return messages.getString(key, (Object[])a);
066      }
067      return "";
068   }
069
070   @Override /* Var */
071   public boolean canResolve(VarResolverSession session) {
072      return session.getBean(Messages.class).isPresent() || session.getBean(RestRequest.class).isPresent();
073   }
074}