| /** |
| * 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 |
| * <p/> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p/> |
| * 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.atlas.catalog.projection; |
| |
| import com.tinkerpop.pipes.Pipe; |
| import com.tinkerpop.pipes.util.Pipeline; |
| import org.apache.atlas.catalog.VertexWrapper; |
| |
| import java.util.Collection; |
| import java.util.Collections; |
| |
| /** |
| * Projection representation. |
| * Used to project properties onto a resource from another source. |
| */ |
| public class Projection { |
| public enum Cardinality {SINGLE, MULTIPLE} |
| |
| private final String m_name; |
| private final Cardinality m_cardinality; |
| protected Pipeline<VertexWrapper, Collection<ProjectionResult>> m_pipeline = new Pipeline<>(); |
| |
| public Projection(String name, Cardinality cardinality) { |
| m_name = name; |
| m_cardinality = cardinality; |
| } |
| |
| public Projection(String name, Cardinality cardinality, Pipe<VertexWrapper, Collection<ProjectionResult>> pipe) { |
| m_name = name; |
| m_cardinality = cardinality; |
| m_pipeline.addPipe(pipe); |
| } |
| |
| public Collection<ProjectionResult> values(VertexWrapper start) { |
| m_pipeline.setStarts(Collections.singleton(start)); |
| return m_pipeline.iterator().next(); |
| } |
| |
| public void addPipe(Pipe<Collection<ProjectionResult>, Collection<ProjectionResult>> p) { |
| m_pipeline.addPipe(p); |
| } |
| |
| public String getName() { |
| return m_name; |
| } |
| |
| public Cardinality getCardinality() { |
| return m_cardinality; |
| } |
| } |