arina-ielchiieva commented on a change in pull request #1797: DRILL-7278: Refactor result set loader projection mechanism URL: https://github.com/apache/drill/pull/1797#discussion_r289939372
########## File path: exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/scan/project/projSet/ProjectionSetFactory.java ########## @@ -0,0 +1,69 @@ +/* + * 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.drill.exec.physical.impl.scan.project.projSet; + +import java.util.List; +import java.util.Map; + +import org.apache.drill.common.expression.SchemaPath; +import org.apache.drill.exec.physical.impl.scan.project.projSet.TypeConverter.CustomTypeTransform; +import org.apache.drill.exec.physical.rowSet.ProjectionSet; +import org.apache.drill.exec.physical.rowSet.project.RequestedTuple; +import org.apache.drill.exec.physical.rowSet.project.RequestedTupleImpl; +import org.apache.drill.exec.record.metadata.ColumnMetadata; +import org.apache.drill.exec.vector.accessor.convert.ColumnConversionFactory; +import org.apache.drill.exec.vector.accessor.convert.StandardConversions.ConversionDefn; + +public class ProjectionSetFactory { + + public static ProjectionSet projectAll() { return new WildcardProjectionSet(null); } + + public static ProjectionSet projectNone() { return EmptyProjectionSet.PROJECT_NONE; } + + public static ProjectionSet wrap(RequestedTuple mapProjection) { + switch (mapProjection.type()) { + case ALL: + return projectAll(); + case NONE: + return projectNone(); + case SOME: + return new ExplicitProjectionSet(mapProjection, null); + default: + throw new IllegalStateException(mapProjection.type().toString()); + } + } + + public static ProjectionSet build(List<SchemaPath> selection) { + if (selection == null) { + return projectAll(); + } + return wrap(RequestedTupleImpl.parse(selection)); + } + + public static CustomTypeTransform simpleTransform(ColumnConversionFactory colFactory) { + return new CustomTypeTransform() { Review comment: May be extract it in `private static final CustomTypeTransform SIMPLE_TRANSFORM = ...`? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services