| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF 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.apache.tinkerpop.gremlin.structure; |
| |
| import org.apache.tinkerpop.gremlin.process.traversal.Path; |
| |
| import java.util.ArrayList; |
| import java.util.HashSet; |
| import java.util.LinkedHashSet; |
| import java.util.Map; |
| import java.util.function.Function; |
| |
| /** |
| * Column references a particular type of column in a complex data structure such as a {@code Map}, a |
| * {@code Map.Entry}, or a {@link Path}. |
| * |
| * @author Marko A. Rodriguez (http://markorodriguez.com) |
| */ |
| public enum Column implements Function<Object, Object> { |
| |
| /** |
| * The keys associated with the data structure. |
| */ |
| keys { |
| @Override |
| public Object apply(final Object object) { |
| if (object instanceof Map) |
| return new LinkedHashSet<>(((Map<?,?>) object).keySet()); |
| else if (object instanceof Map.Entry) |
| return ((Map.Entry) object).getKey(); |
| else if (object instanceof Path) |
| return new ArrayList<>(((Path) object).labels()); |
| else |
| throw new IllegalArgumentException("The provided object does not have accessible keys: " + object.getClass()); |
| } |
| }, |
| /** |
| * The values associated with the data structure. |
| */ |
| values { |
| @Override |
| public Object apply(final Object object) { |
| if (object instanceof Map) |
| return new ArrayList<>(((Map<?,?>) object).values()); |
| else if (object instanceof Map.Entry) |
| return ((Map.Entry) object).getValue(); |
| else if (object instanceof Path) |
| return new ArrayList<>(((Path) object).objects()); |
| else |
| throw new IllegalArgumentException("The provided object does not have accessible keys: " + object.getClass()); |
| } |
| } |
| |
| |
| } |