001/* 002 * Copyright (c) 2016-2017 Chris K Wensel <chris@wensel.net>. 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 java.util.Map; 024 025import cascading.operation.Function; 026import cascading.tuple.Fields; 027import cascading.tuple.TupleEntry; 028 029/** 030 * Class NestedCreateFunction is the base class for {@link Function} implementations that want to simply store 031 * values in a new nested object tree. 032 * <p> 033 * All argument values referenced by the {@code pointerMap} will be set on a new instance of the root node. 034 * <p> 035 * That is, every Fields instance in the pointer map is expected to have a corresponding argument passed to the operation. 036 * <p> 037 * The pointer path mapped to any given Fields instance in the {@code pointerMap} will be used as the location to set on the 038 * root node. 039 * <p> 040 * If a {@code pointerMap} is not provided, the resolved argument fields will be mapped to the root of the node. This is a 041 * convenience for quickly pivoting a Tuple into an nested object with the same attributes. 042 */ 043public abstract class NestedCreateFunction<Node, Result> extends NestedBaseFunction<Node, Result> 044 { 045 public NestedCreateFunction( NestedCoercibleType<Node, Result> nestedCoercibleType, Fields fieldDeclaration ) 046 { 047 super( nestedCoercibleType, fieldDeclaration ); 048 } 049 050 public NestedCreateFunction( NestedCoercibleType<Node, Result> nestedCoercibleType, Fields fieldDeclaration, String rootPointer ) 051 { 052 super( nestedCoercibleType, fieldDeclaration, rootPointer ); 053 } 054 055 public NestedCreateFunction( NestedCoercibleType nestedCoercibleType, Fields fieldDeclaration, Map<Fields, String> pointerMap ) 056 { 057 super( nestedCoercibleType, fieldDeclaration, pointerMap ); 058 } 059 060 @Override 061 protected Node getNode( TupleEntry arguments ) 062 { 063 return getRootNode(); 064 } 065 }