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.data;
  
  import static java.util.Collections.unmodifiableMap;
  import static java.util.stream.Collector.Characteristics.UNORDERED;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.stream.Collector;
  import org.openqa.selenium.Capabilities;
  import org.openqa.selenium.json.JsonInput;
  
  public class CapabilityCount {
  
    private final Map<Capabilities, Integer> counts;
  
    public CapabilityCount(Map<Capabilities, Integer> counts) {
      this.counts = unmodifiableMap(new HashMap<>(counts));
    }
  
    public Map<Capabilities, Integer> getCounts() {
      return counts;
    }
  
    private Object toJson() {
      return counts.entrySet().stream()
          .map(
              entry -> {
                Map<Object, Object> toReturn = new HashMap<>();
                toReturn.put("capabilities", entry.getKey());
                toReturn.put("count", entry.getValue());
                return toReturn;
              })
          .collect(
              Collector.of(
                  ArrayList::new,
                  ArrayList::add,
                  (l, r) -> {
                    l.addAll(r);
                    return l;
                  },
                  Collections::unmodifiableList,
                  UNORDERED));
    }
  
    private static CapabilityCount fromJson(JsonInput input) {
      Map<Capabilities, Integer> toReturn = new HashMap<>();
  
      input.beginArray();
      while (input.hasNext()) {
        Capabilities caps = null;
        int count = 0;
        input.beginObject();
        while (input.hasNext()) {
          switch (input.nextName()) {
            case "capabilities":
              caps = input.read(Capabilities.class);
              break;
  
            case "count":
              count = input.nextNumber().intValue();
              break;
  
            default:
              input.skipValue();
              break;
          }
        }
        input.endObject();
  
        toReturn.put(caps, count);
      }
      input.endArray();
  
      return new CapabilityCount(toReturn);
    }
  }
  