001/*
002 * Copyright (c) 2007-2017 Xplenty, Inc. All Rights Reserved.
003 *
004 * Project and contact information: http://www.cascading.org/
005 *
006 * This file is part of the Cascading project.
007 *
008 * Licensed under the Apache License, Version 2.0 (the "License");
009 * you may not use this file except in compliance with the License.
010 * You may obtain a copy of the License at
011 *
012 *     http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing, software
015 * distributed under the License is distributed on an "AS IS" BASIS,
016 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
017 * See the License for the specific language governing permissions and
018 * limitations under the License.
019 */
020
021package cascading.flow.planner.iso.assertion;
022
023import cascading.flow.planner.PlannerContext;
024import cascading.flow.planner.graph.ElementGraph;
025import cascading.flow.planner.iso.expression.ExpressionGraph;
026import cascading.flow.planner.iso.finder.GraphFinder;
027import cascading.flow.planner.iso.finder.Match;
028import cascading.flow.planner.iso.transformer.Transformed;
029
030/**
031 * TODO: add level for warning or error, and fail on errors
032 */
033public abstract class GraphAssert<E extends ElementGraph>
034  {
035  public enum AssertionType
036    {
037      Unsupported,
038      Illegal
039    }
040
041  private final GraphFinder finder;
042  private final String message;
043  private AssertionType assertionType = AssertionType.Illegal;
044
045  public GraphAssert( ExpressionGraph expressionGraph, String message )
046    {
047    this( expressionGraph, message, null );
048    }
049
050  public GraphAssert( ExpressionGraph expressionGraph, String message, AssertionType assertionType )
051    {
052    this.finder = new GraphFinder( expressionGraph );
053    this.message = message;
054
055    if( assertionType != null )
056      this.assertionType = assertionType;
057    }
058
059  protected abstract Transformed transform( PlannerContext plannerContext, E graph );
060
061  public Asserted assertion( PlannerContext plannerContext, E graph )
062    {
063    Transformed<E> transform = transform( plannerContext, graph );
064
065    if( transform != null && transform.getEndGraph() != null )
066      graph = transform.getEndGraph();
067
068    Match match = finder.findFirstMatch( plannerContext, graph );
069
070    Asserted asserted = new Asserted( plannerContext, this, graph, message, assertionType, match );
071
072    if( transform != null )
073      asserted.addChildTransform( transform );
074
075    return asserted;
076    }
077  }