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.remote;
  
  import com.google.common.base.Function;
  import com.google.common.collect.Iterables;
  import com.google.common.collect.Lists;
  import com.google.common.collect.Maps;
  import java.util.Collection;
  import java.util.Map;
  import org.openqa.selenium.WebElement;
  
  /**
   * Reconstitutes {@link WebElement}s from their JSON representation. Will recursively convert Lists
   * and Maps to catch nested references. All other values pass through the converter unchanged.
   */
  public class JsonToWebElementConverter implements Function<Object, Object> {
  
    private final RemoteWebDriver driver;
  
    public JsonToWebElementConverter(RemoteWebDriver driver) {
      this.driver = driver;
    }
  
    @Override
    public Object apply(Object result) {
      if (result instanceof Collection<?>) {
        Collection<?> results = (Collection<?>) result;
        return Lists.newArrayList(Iterables.transform(results, this));
      }
  
      if (result instanceof Map<?, ?>) {
        Map<?, ?> resultAsMap = (Map<?, ?>) result;
        String elementKey = getElementKey(resultAsMap);
        if (null != elementKey) {
          RemoteWebElement element = newRemoteWebElement();
          element.setId(String.valueOf(resultAsMap.get(elementKey)));
          return element;
        }
  
        String shadowKey = getShadowRootKey(resultAsMap);
        if (null != shadowKey) {
          return new ShadowRoot(driver, String.valueOf(resultAsMap.get(shadowKey)));
        }
  
        return Maps.transformValues(resultAsMap, this);
      }
  
      if (result instanceof RemoteWebElement) {
        return setOwner((RemoteWebElement) result);
      }
  
      if (result instanceof Number) {
        if (result instanceof Float || result instanceof Double) {
          return ((Number) result).doubleValue();
        }
        return ((Number) result).longValue();
      }
  
      return result;
    }
  
    protected RemoteWebElement newRemoteWebElement() {
      return setOwner(new RemoteWebElement());
    }
  
    private RemoteWebElement setOwner(RemoteWebElement element) {
      if (driver != null) {
        element.setParent(driver);
        element.setFileDetector(driver.getFileDetector());
      }
      return element;
    }
  
    private String getElementKey(Map<?, ?> resultAsMap) {
      for (Dialect d : Dialect.values()) {
        String elementKeyForDialect = d.getEncodedElementKey();
        if (resultAsMap.containsKey(elementKeyForDialect)) {
          return elementKeyForDialect;
        }
      }
      return null;
    }
  
    private String getShadowRootKey(Map<?, ?> resultAsMap) {
      for (Dialect d : Dialect.values()) {
        String shadowRootElementKey = d.getShadowRootElementKey();
        if (resultAsMap.containsKey(shadowRootElementKey)) {
          return shadowRootElementKey;
        }
      }
      return null;
    }
  }
  