code: /*
   * Copyright (c) 2019 the Eclipse Milo Authors
   *
   * This program and the accompanying materials are made
   * available under the terms of the Eclipse Public License 2.0
   * which is available at https://www.eclipse.org/legal/epl-2.0/
   *
   * SPDX-License-Identifier: EPL-2.0
   */
  
  package org.eclipse.milo.opcua.stack.core;
  
  import java.util.Optional;
  
  import org.eclipse.milo.opcua.stack.core.types.builtin.StatusCode;
  
  public interface UaExceptionStatus {
  
      /**
       * @return the message associated with the exception.
       */
      String getMessage();
  
      /**
       * @return the {@link StatusCode} associated with the exception.
       */
      StatusCode getStatusCode();
  
      /**
       * If {@code ex} is a {@link UaExceptionStatus}, or if a {@link UaExceptionStatus} can be found by walking up the
       * exception cause chain, return it.
       *
       * @param ex the {@link Throwable} to extract from.
       * @return a {@link UaExceptionStatus} if one was present in the exception chain.
       */
      static Optional<UaExceptionStatus> extract(Throwable ex) {
          if (ex instanceof UaExceptionStatus) {
              return Optional.of((UaExceptionStatus) ex);
          } else {
              Throwable cause = ex.getCause();
              return cause != null ?
                  extract(cause) : Optional.empty();
          }
      }
  
  }
  