flink-libraries/flink-table/src/main/java/org/apache/flink/table/sources/parquet/VectorizedRowInputParquetFormat.java

/*
 * 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.flink.table.sources.parquet;

import org.apache.flink.api.java.typeutils.ResultTypeQueryable;
import org.apache.flink.api.java.typeutils.RowTypeInfo;
import org.apache.flink.core.fs.Path;
import org.apache.flink.table.api.types.InternalType;
import org.apache.flink.table.api.types.TypeConverters;
import org.apache.flink.types.Row;

import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.parquet.filter2.predicate.FilterPredicate;

/**
 * A subclass of {@link ParquetInputFormat} to read from Parquet files and convert to {@link Row}.
 */
public class VectorizedRowInputParquetFormat extends ParquetInputFormat<Row, Row> implements ResultTypeQueryable<Row> {

	private static final long serialVersionUID = -2569974518641072883L;

	private transient Row reuse;

	public VectorizedRowInputParquetFormat(Path filePath, InternalType[] fieldTypes, String[] fieldNames) {
		super(filePath, fieldTypes, fieldNames);
	}

	@Override
	protected RecordReader createReader(FilterPredicate filter) {
		return new ParquetVectorizedRowReader(fieldTypes, fieldNames);
	}

	@Override
	public RowTypeInfo getProducedType() {
		return new RowTypeInfo(TypeConverters.createExternalTypeInfoFromDataTypes(fieldTypes));
	}

	@Override
	protected Row convert(Row current) {
		if (reuse == null) {
			return Row.copy(current);
		} else {
			for (int i = 0; i < current.getArity(); ++i) {
				reuse.setField(i, current.getField(i));
			}
			return reuse;
		}
	}
}