content: /*
   *  Licensed to the Apache Software Foundation (ASF) under one
   *  or more contributor license agreements.  See the NOTICE file
   *  distributed with this work for additional information
   *  regarding copyright ownership.  The ASF licenses this file
   *  to you under the Apache License, Version 2.0 (the
   *  "License"); you may not use this file except in compliance
   *  with the License.  You may obtain a copy of the License at
   *
   *        http://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing,
   *  software distributed under the License is distributed on an
   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   *  KIND, either express or implied.  See the License for the
   *  specific language governing permissions and limitations
   *  under the License.
   */
  package org.apache.causeway.viewer.restfulobjects.viewer.mappers;
  
  import java.util.Optional;
  
  import org.apache.causeway.commons.collections.Can;
  import org.apache.causeway.commons.functional.Try;
  import org.apache.causeway.commons.internal.reflection._Reflect;
  import org.apache.causeway.core.metamodel.methods.MethodFinder;
  import org.apache.causeway.viewer.restfulobjects.applib.RestfulResponse;
  import org.apache.causeway.viewer.restfulobjects.applib.RestfulResponse.HttpStatusCode;
  
  import lombok.experimental.UtilityClass;
  
  @UtilityClass
  final class FailureUtil {
  
      public static HttpStatusCode getFailureStatusCodeIfAny(final Throwable ex) {
  
          return MethodFinder
              .publicOnly(ex.getClass(), Can.ofSingleton("getErrorCode"))
              .withRequiredReturnType(int.class)
              .streamMethodsMatchingSignature(MethodFinder.NO_ARG)
              .findFirst()
              .map(errorCodeGetter->_Reflect.invokeMethodOn(errorCodeGetter.method(), ex))
              .map(Try::getValue)
              .map(Optional::stream)
              .filter(Integer.class::isInstance)
              .map(Integer.class::cast)
              .map(RestfulResponse.HttpStatusCode::statusFor)
              .orElse(null);
      }
  
  }
  