code: // Licensed to the Software Freedom Conservancy (SFC) under one
  // or more contributor license agreements.  See the NOTICE file
  // distributed with this work for additional information
  // regarding copyright ownership.  The SFC 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.openqa.selenium.grid.sessionqueue;
  
  import static org.openqa.selenium.remote.tracing.HttpTracing.newSpanAsChildOf;
  import static org.openqa.selenium.remote.tracing.Tags.HTTP_REQUEST;
  import static org.openqa.selenium.remote.tracing.Tags.HTTP_RESPONSE;
  
  import java.io.UncheckedIOException;
  import org.openqa.selenium.SessionNotCreatedException;
  import org.openqa.selenium.grid.data.RequestId;
  import org.openqa.selenium.internal.Either;
  import org.openqa.selenium.internal.Require;
  import org.openqa.selenium.remote.http.Contents;
  import org.openqa.selenium.remote.http.HttpHandler;
  import org.openqa.selenium.remote.http.HttpRequest;
  import org.openqa.selenium.remote.http.HttpResponse;
  import org.openqa.selenium.remote.tracing.Span;
  import org.openqa.selenium.remote.tracing.Tracer;
  
  class SessionNotCreated implements HttpHandler {
  
    private final Tracer tracer;
    private final NewSessionQueue queue;
    private final RequestId requestId;
  
    public SessionNotCreated(Tracer tracer, NewSessionQueue queue, RequestId requestId) {
      this.tracer = Require.nonNull("Tracer", tracer);
      this.queue = Require.nonNull("New Session Queue", queue);
      this.requestId = Require.nonNull("Request ID", requestId);
    }
  
    @Override
    public HttpResponse execute(HttpRequest req) throws UncheckedIOException {
      try (Span span = newSpanAsChildOf(tracer, req, "sessionqueue.created_bad")) {
        HTTP_REQUEST.accept(span, req);
  
        String message = Contents.fromJson(req, String.class);
        SessionNotCreatedException exception = new SessionNotCreatedException(message);
        queue.complete(requestId, Either.left(exception));
  
        HttpResponse res = new HttpResponse();
        HTTP_RESPONSE.accept(span, res);
        return res;
      }
    }
  }
  