// Copyright 2016 The Nomulus Authors. All Rights Reserved.
//
// Licensed 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 google.registry.util;

import com.google.appengine.api.datastore.Key;
import com.google.common.base.Function;
import com.google.common.base.Optional;

/** Utility methods for working with the AppEngine datastore service. */
public class DatastoreServiceUtils {

  /** Helper function that extracts the kind from a regular datastore entity key. */
  public static final Function<Key, String> KEY_TO_KIND_FUNCTION = new Function<Key, String>() {
      @Override
      public String apply(Key key) {
        return key.getKind();
      }};

  /** Returns the name or id of a key, which may be a string or a long. */
  public static Object getNameOrId(Key key) {
    return Optional.<Object>fromNullable(key.getName()).or(key.getId());
  }
}