| /* |
| * 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.parquet.cascading; |
| |
| import org.apache.parquet.schema.MessageType; |
| import org.apache.parquet.schema.Type; |
| |
| import cascading.tuple.Fields; |
| |
| import java.util.List; |
| import java.util.ArrayList; |
| |
| public class SchemaIntersection { |
| |
| private final MessageType requestedSchema; |
| private final Fields sourceFields; |
| |
| public SchemaIntersection(MessageType fileSchema, Fields requestedFields) { |
| if(requestedFields == Fields.UNKNOWN) |
| requestedFields = Fields.ALL; |
| |
| Fields newFields = Fields.NONE; |
| List<Type> newSchemaFields = new ArrayList<Type>(); |
| int schemaSize = fileSchema.getFieldCount(); |
| |
| for (int i = 0; i < schemaSize; i++) { |
| Type type = fileSchema.getType(i); |
| Fields name = new Fields(type.getName()); |
| |
| if(requestedFields.contains(name)) { |
| newFields = newFields.append(name); |
| newSchemaFields.add(type); |
| } |
| } |
| |
| this.sourceFields = newFields; |
| this.requestedSchema = new MessageType(fileSchema.getName(), newSchemaFields); |
| } |
| |
| public MessageType getRequestedSchema() { |
| return requestedSchema; |
| } |
| |
| public Fields getSourceFields() { |
| return sourceFields; |
| } |
| } |