001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.juneau.rest.arg;
018
019import org.apache.juneau.commons.reflect.*;
020import org.apache.juneau.rest.*;
021import org.apache.juneau.rest.annotation.*;
022
023/**
024 * Resolves method parameters annotated with {@link Method} on {@link RestOp}-annotated Java methods.
025 *
026 * <p>
027 * The parameter value is resolved using:
028 * <p class='bjava'>
029 *    <jv>opSession</jv>
030 *       .{@link RestOpSession#getRequest() getRequest}()
031 *       .{@link RestRequest#getMethod() getMethod}();
032 * </p>
033 *
034 * <p>
035 * The parameter type must be {@link String}.
036 *
037 * <h5 class='section'>See Also:</h5><ul>
038 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/JavaMethodParameters">Java Method Parameters</a>
039 * </ul>
040 */
041public class MethodArg implements RestOpArg {
042
043   private static final AnnotationProvider AP = AnnotationProvider.INSTANCE;
044
045   /**
046    * Static creator.
047    *
048    * @param paramInfo The Java method parameter being resolved.
049    * @return A new {@link MethodArg}, or <jk>null</jk> if the parameter isn't annotated with {@link Method}.
050    */
051   public static MethodArg create(ParameterInfo paramInfo) {
052      if (AP.has(Method.class, paramInfo))
053         return new MethodArg();
054      return null;
055   }
056
057   /**
058    * Constructor.
059    */
060   protected MethodArg() {}
061
062   @Override /* Overridden from RestOpArg */
063   public Object resolve(RestOpSession opSession) throws Exception {
064      return opSession.getRequest().getMethod();
065   }
066}