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;
  
  import com.google.common.net.InetAddresses;
  import org.openqa.selenium.environment.webserver.AppServer;
  import org.openqa.selenium.internal.Require;
  
  public class DomainHelper {
  
    private final AppServer appServer;
  
    public DomainHelper(AppServer appServer) {
      this.appServer = appServer;
    }
  
    public String getUrlForFirstValidHostname(String path) {
      Require.precondition(
          isValidHostname(appServer.getHostName()),
          "Expected valid hostname but was %s",
          appServer.getHostName());
      return appServer.whereIs(path);
    }
  
    public String getSecureUrlForFirstValidHostname(String path) {
      Require.precondition(
          isValidHostname(appServer.getHostName()),
          "Expected valid hostname but was %s",
          appServer.getHostName());
      return appServer.whereIsSecure(path);
    }
  
    public String getUrlForSecondValidHostname(String path) {
      Require.precondition(
          isValidHostname(appServer.getAlternateHostName()),
          "Expected valid hostname but was %s",
          appServer.getAlternateHostName());
      return appServer.whereElseIs(path);
    }
  
    public boolean checkIsOnValidHostname() {
      boolean correct = getHostName() != null && isValidHostname(getHostName());
      if (!correct) {
        System.out.println(
            "Skipping test: unable to find domain name to use, hostname: " + getHostName());
      }
      return correct;
    }
  
    public boolean checkIsOnValidSubDomain() {
      boolean correct = getHostName() != null && isValidSubDomain(getHostName());
  
      if (!correct) {
        System.out.println(
            "Skipping test: unable to find sub domain name to use, hostname: " + getHostName());
      }
      return correct;
    }
  
    public boolean checkHasValidAlternateHostname() {
      String hostname = appServer.getAlternateHostName();
      boolean correct = getHostName() != null && isValidHostname(hostname);
      if (!correct) {
        System.out.println(
            "Skipping test: unable to find alternate domain name to use, hostname: " + hostname);
      }
      return correct;
    }
  
    private boolean isValidSubDomain(String hostname) {
      /*
       * /etc/hosts needs to have e.g.
       *
       * 127.0.0.1       sub.selenium.tests
       *
       */
      return hostname.split("\\.").length >= 3;
    }
  
    public boolean isValidHostname(String hostname) {
      // Strip the IPv6 zone index, if present. For example, "fe80::1%eth0" becomes "fe80::1".
      int zoneIndexStart = hostname.indexOf('%');
      if (zoneIndexStart >= 0) {
        hostname = hostname.substring(0, zoneIndexStart);
      }
      return !InetAddresses.isInetAddress(hostname) && !"localhost".equals(hostname);
    }
  
    public String getHostName() {
      return appServer.getHostName();
    }
  }
  