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.environment.webserver;
  
  import static org.openqa.selenium.remote.http.Contents.utf8String;
  
  import java.io.UncheckedIOException;
  import org.openqa.selenium.remote.http.HttpHandler;
  import org.openqa.selenium.remote.http.HttpRequest;
  import org.openqa.selenium.remote.http.HttpResponse;
  
  public class SleepingHandler implements HttpHandler {
  
    private static final String RESPONSE_STRING_FORMAT =
        "<html><head><title>Done</title></head><body>Slept for %ss</body></html>";
  
    @Override
    public HttpResponse execute(HttpRequest req) throws UncheckedIOException {
      String duration = req.getQueryParameter("time");
      long timeout = Long.parseLong(duration) * 1000;
  
      reallySleep(timeout);
  
      return new HttpResponse()
          .setHeader("Content-Type", "text/html")
          // Dont Cache Anything  at the browser
          .setHeader("Cache-Control", "no-cache")
          .setHeader("Pragma", "no-cache")
          .setHeader("Expires", "0")
          .setContent(utf8String(String.format(RESPONSE_STRING_FORMAT, duration)));
    }
  
    private void reallySleep(long timeout) {
      long start = System.currentTimeMillis();
      try {
        Thread.sleep(timeout);
        while ((System.currentTimeMillis() - start) < timeout) {
          Thread.sleep(20);
        }
      } catch (InterruptedException ignore) {
      }
    }
  }
  