001/*
002 * Copyright (c) 2016-2017 Chris K Wensel. 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.nested.core;
022
023import cascading.operation.FunctionCall;
024import cascading.operation.OperationCall;
025import cascading.tuple.Fields;
026import cascading.tuple.TupleEntry;
027
028/**
029 *
030 */
031public abstract class NestedSpecBaseOperation<Node, Result, Context> extends NestedBaseOperation<Node, Result, Context>
032  {
033  public NestedSpecBaseOperation( NestedCoercibleType<Node, Result> nestedCoercibleType, Fields fieldDeclaration )
034    {
035    super( nestedCoercibleType, fieldDeclaration );
036    }
037
038  public NestedSpecBaseOperation( NestedCoercibleType<Node, Result> nestedCoercibleType, int numArgs, Fields fieldDeclaration )
039    {
040    super( nestedCoercibleType, numArgs, fieldDeclaration );
041    }
042
043  protected abstract boolean isInto();
044
045  protected Node getResultNode( OperationCall<?> operationCall )
046    {
047    if( isInto() )
048      return getArgument( operationCall );
049    else
050      return getRootNode();
051    }
052
053  protected Node getArgument( OperationCall<?> operationCall )
054    {
055    TupleEntry arguments = ( (FunctionCall<Object>) operationCall ).getArguments();
056
057    Node object = (Node) arguments.getObject( arguments.size() - 1, getCoercibleType() );
058
059    return deepCopy( object );
060    }
061  }