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.server.arg;
018
019import org.apache.juneau.commons.reflect.*;
020import org.apache.juneau.rest.server.*;
021
022/**
023 * Resolves method parameters annotated with {@link Method} on {@link RestOp}-annotated Java methods.
024 *
025 * <p>
026 * The parameter value is resolved using:
027 * <p class='bjava'>
028 *    <jv>opSession</jv>
029 *       .{@link RestOpSession#getRequest() getRequest}()
030 *       .{@link RestRequest#getMethod() getMethod}();
031 * </p>
032 *
033 * <p>
034 * The parameter type must be {@link String}.
035 *
036 * <h5 class='section'>See Also:</h5><ul>
037 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/JavaMethodParameters">Java Method Parameters</a>
038 * </ul>
039 */
040public class MethodArg implements RestOpArg {
041
042   private static final AnnotationProvider AP = AnnotationProvider.INSTANCE;
043
044   /**
045    * Static creator.
046    *
047    * @param paramInfo The Java method parameter being resolved. Must not be <jk>null</jk>.
048    * @return A new {@link MethodArg}, or <jk>null</jk> if the parameter isn't annotated with {@link Method}.
049    */
050   public static MethodArg create(ParameterInfo paramInfo) {
051      if (AP.has(Method.class, paramInfo))
052         return new MethodArg();
053      return null;
054   }
055
056   /**
057    * Constructor.
058    */
059   protected MethodArg() {}
060
061   @Override /* Overridden from RestOpArg */
062   public Object resolve(RestOpSession opSession) throws Exception {
063      return opSession.getRequest().getMethod();
064   }
065}