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.testing.drivers;
  
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.util.HashSet;
  import java.util.LinkedList;
  import java.util.Objects;
  import java.util.Optional;
  import java.util.Set;
  import java.util.function.Supplier;
  import java.util.logging.Level;
  import java.util.stream.Stream;
  import org.openqa.selenium.Capabilities;
  import org.openqa.selenium.ImmutableCapabilities;
  import org.openqa.selenium.WebDriver;
  
  public class WebDriverBuilder implements Supplier<WebDriver> {
  
    private static final LinkedList<Runnable> shutdownActions = new LinkedList<>();
    private static final Set<WebDriver> managedDrivers = new HashSet<>();
  
    static {
      shutdownActions.add(() -> managedDrivers.forEach(WebDriver::quit));
      Runtime.getRuntime().addShutdownHook(new Thread(() -> shutdownActions.forEach(Runnable::run)));
    }
  
    private final Browser toBuild;
  
    public WebDriverBuilder() {
      this(Browser.detect());
    }
  
    public WebDriverBuilder(Browser toBuild) {
      this.toBuild = Optional.ofNullable(toBuild).orElse(Browser.CHROME);
    }
  
    static void addShutdownAction(Runnable action) {
      shutdownActions.add(action);
    }
  
    @Override
    public WebDriver get() {
      return get(new ImmutableCapabilities());
    }
  
    public WebDriver get(Capabilities desiredCapabilities) {
      Objects.requireNonNull(desiredCapabilities, "Capabilities to use must be set");
      Capabilities desiredCaps =
          Objects.requireNonNull(Browser.detect()).getCapabilities().merge(desiredCapabilities);
  
      WebDriver driver =
          Stream.of(
                  new ExternalDriverSupplier(desiredCaps),
                  new GridSupplier(desiredCaps),
                  new RemoteSupplier(desiredCaps),
                  new TestInternetExplorerSupplier(desiredCaps),
                  new DefaultDriverSupplier(desiredCaps))
              .map(Supplier::get)
              .filter(Objects::nonNull)
              .findFirst()
              .orElseThrow(
                  () ->
                      new RuntimeException(
                          "Cannot instantiate driver instance: " + desiredCapabilities));
  
      modifyLogLevel(driver);
      managedDrivers.add(driver);
      return driver;
    }
  
    private void modifyLogLevel(WebDriver driver) {
      Class<?>[] args = {Level.class};
      Method setLogLevel;
      try {
        setLogLevel = driver.getClass().getMethod("setLogLevel", args);
  
        String value = System.getProperty("selenium.browser.log_level", "INFO");
        LogLevel level = LogLevel.valueOf(value);
        setLogLevel.invoke(driver, level.getLevel());
      } catch (NoSuchMethodException e) {
      } catch (IllegalAccessException | InvocationTargetException e) {
        throw new RuntimeException(e);
      }
    }
  
    private enum LogLevel {
      OFF("OFF", Level.OFF),
      DEBUG("DEBUG", Level.FINE),
      INFO("INFO", Level.INFO),
      WARNING("WARNING", Level.WARNING),
      ERROR("ERROR", Level.SEVERE);
  
      @SuppressWarnings("unused")
      private final String value;
  
      private final Level level;
  
      LogLevel(String value, Level level) {
        this.value = value;
        this.level = level;
      }
  
      public Level getLevel() {
        return level;
      }
    }
  }
  