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;
018
019import java.lang.reflect.*;
020
021import org.apache.juneau.http.response.*;
022import org.apache.juneau.reflect.*;
023import org.apache.juneau.rest.arg.*;
024import org.apache.juneau.rest.stats.*;
025
026/**
027 * A specialized invoker for methods that are called during a servlet request.
028 *
029 * <h5 class='section'>See Also:</h5><ul>
030 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/RestContext">RestContext</a>
031 * </ul>
032 */
033public class RestOpInvoker extends MethodInvoker {
034
035   private final RestOpArg[] opArgs;
036
037   /**
038    * Constructor.
039    *
040    * @param m The method being wrapped.
041    * @param opArgs The parameter resolvers.
042    * @param stats The instrumentor.
043    */
044   public RestOpInvoker(Method m, RestOpArg[] opArgs, MethodExecStats stats) {
045      super(m, stats);
046      this.opArgs = opArgs;
047   }
048
049   /**
050    * Invokes this method from the specified {@link RestSession}.
051    *
052    * @param opSession The REST call.
053    * @throws Throwable If an error occurred during either parameter resolution or method invocation.
054    */
055   public void invoke(RestOpSession opSession) throws Throwable {
056      Object[] args = new Object[opArgs.length];
057      for (int i = 0; i < opArgs.length; i++) {
058         ParamInfo pi = inner().getParam(i);
059         try {
060            args[i] = opArgs[i].resolve(opSession);
061         } catch (BasicHttpException e) {
062            throw e;
063         } catch (Exception e) {
064            throw new BadRequest(e, "Could not resolve parameter {0} of type ''{1}'' on method ''{2}''.", i, pi.getParameterType(), getFullName());
065         }
066      }
067      try {
068         RestSession session = opSession.getRestSession();
069         RestRequest req = opSession.getRequest();
070         RestResponse res = opSession.getResponse();
071
072         Object output = super.invoke(session.getResource(), args);
073
074         // Handle manual call to req.setDebug().
075         Boolean debug = req.getAttribute("Debug").as(Boolean.class).orElse(null);
076         if (debug == Boolean.TRUE) {
077            session.debug(true);
078         } else if (debug == Boolean.FALSE) {
079            session.debug(false);
080         }
081
082         if (! inner().hasReturnType(Void.TYPE))
083            if (output != null || ! res.getOutputStreamCalled())
084               res.setContent(output);
085
086      } catch (IllegalAccessException|IllegalArgumentException e) {
087         throw new InternalServerError(e, "Error occurred invoking method ''{0}''.", inner().getFullName());
088      } catch (InvocationTargetException e) {
089         RestResponse res = opSession.getResponse();
090         Throwable e2 = e.getTargetException();
091         res.setStatus(500);  // May be overridden later.
092         res.setContent(opSession.getRestContext().convertThrowable(e2));
093      }
094   }
095}