| /* |
| * 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.expr.fn.impl; |
| |
| import org.apache.drill.exec.expr.DrillSimpleFunc; |
| import org.apache.drill.exec.expr.annotations.FunctionTemplate; |
| import org.apache.drill.exec.expr.annotations.Output; |
| import org.apache.drill.exec.expr.annotations.Param; |
| import org.apache.drill.exec.vector.complex.reader.FieldReader; |
| import org.apache.drill.exec.vector.complex.writer.BaseWriter; |
| |
| /** |
| * Implementation of Calcite's ROW(col1, col2, ..., colN) constructor function. |
| * Function expects field name before every value. |
| * |
| * @see org.apache.drill.exec.planner.logical.DrillOptiq |
| */ |
| @FunctionTemplate(name = "row", scope = FunctionTemplate.FunctionScope.SIMPLE, |
| isVarArg = true, isInternal = true) |
| public class RowConstructorFunction implements DrillSimpleFunc { |
| |
| @Param |
| FieldReader[] in; |
| |
| @Output |
| BaseWriter.ComplexWriter out; |
| |
| @Override |
| public void setup() { |
| } |
| |
| @Override |
| public void eval() { |
| org.apache.drill.exec.vector.complex.writer.BaseWriter.MapWriter writer = out.rootAsMap(); |
| for (int nameIdx = 0, valIdx = 1; valIdx < in.length; nameIdx += 2, valIdx += 2) { |
| String fieldName = in[nameIdx].readObject().toString(); |
| FieldReader reader = in[valIdx]; |
| org.apache.drill.exec.vector.complex.MapUtility |
| .writeToMapFromReader(reader, writer, fieldName, "RowConstructorFunction"); |
| } |
| } |
| } |