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 class UaException extends Exception implements UaExceptionStatus {
  
      private final StatusCode statusCode;
  
      public UaException(long statusCode) {
          this.statusCode = new StatusCode(statusCode);
      }
  
      public UaException(StatusCode statusCode) {
          this.statusCode = statusCode;
      }
  
      public UaException(Throwable cause) {
          super(cause);
  
          this.statusCode = new StatusCode(StatusCodes.Bad_InternalError);
      }
  
      public UaException(long statusCode, Throwable cause) {
          super(cause);
  
          this.statusCode = new StatusCode(statusCode);
      }
  
      public UaException(long statusCode, String message) {
          super(message);
  
          this.statusCode = new StatusCode(statusCode);
      }
  
      public UaException(long statusCode, String message, Throwable cause) {
          super(message, cause);
  
          this.statusCode = new StatusCode(statusCode);
      }
  
      public UaException(StatusCode statusCode, String message) {
          super(message);
  
          this.statusCode = statusCode;
      }
  
      @Override
      public StatusCode getStatusCode() {
          return statusCode;
      }
  
      @Override
      public String getMessage() {
          String message = super.getMessage();
  
          if (message == null || message.isEmpty()) {
              Optional<String[]> lookup = StatusCodes.lookup(statusCode.getValue());
  
              String status = lookup.map(nd -> nd[0]).orElse(statusCode.toString());
              String description = lookup.map(nd -> nd[1]).orElse("");
  
              if (description.isEmpty()) {
                  message = String.format("status=%s", status);
              } else {
                  message = String.format("status=%s, description=%s", status, description);
              }
          }
  
          return message;
      }
  
      @Override
      public String toString() {
          String clazzName = getClass().getSimpleName();
  
          Optional<String[]> lookup = StatusCodes.lookup(statusCode.getValue());
  
          String status = lookup.map(nd -> nd[0]).orElse(statusCode.toString());
  
          String message = super.getMessage();
          if (message == null) {
              message = lookup.map(nd -> nd[1]).orElse("");
          }
  
          if (message.isEmpty()) {
              return String.format("%s: status=%s", clazzName, status);
          } else {
              return String.format("%s: status=%s, message=%s", clazzName, status, message);
          }
      }
  
      /**
       * If {@code ex} is a {@link UaException}, or if a {@link UaException} can be found by walking up the exception
       * cause chain, return it.
       *
       * @param ex the {@link Throwable} to extract from.
       * @return a {@link UaException} if one was present in the exception chain.
       */
      public static Optional<UaException> extract(Throwable ex) {
          if (ex instanceof UaException) {
              return Optional.of((UaException) ex);
          } else {
              Throwable cause = ex.getCause();
              return cause != null ?
                  extract(cause) : Optional.empty();
          }
      }
  
      public static Optional<StatusCode> extractStatusCode(Throwable ex) {
          if (ex instanceof UaExceptionStatus) {
              return Optional.of(((UaExceptionStatus) ex).getStatusCode());
          } else {
              Throwable cause = ex.getCause();
              return cause != null ?
                  extractStatusCode(cause) : Optional.empty();
          }
      }
  
  }
  