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.node;
  
  import static org.openqa.selenium.remote.http.Contents.asJson;
  
  import com.google.common.collect.ImmutableMap;
  import java.io.UncheckedIOException;
  import org.openqa.selenium.internal.Require;
  import org.openqa.selenium.remote.SessionId;
  import org.openqa.selenium.remote.http.HttpHandler;
  import org.openqa.selenium.remote.http.HttpRequest;
  import org.openqa.selenium.remote.http.HttpResponse;
  
  class IsSessionOwner implements HttpHandler {
  
    private final Node node;
    private final SessionId id;
  
    IsSessionOwner(Node node, SessionId id) {
      this.node = Require.nonNull("Node", node);
      this.id = Require.nonNull("Session id", id);
    }
  
    @Override
    public HttpResponse execute(HttpRequest req) throws UncheckedIOException {
      return new HttpResponse().setContent(asJson(ImmutableMap.of("value", node.isSessionOwner(id))));
    }
  }
  