paleolimbot commented on code in PR #2971: URL: https://github.com/apache/parquet-java/pull/2971#discussion_r2084921398
########## parquet-column/src/main/java/org/apache/parquet/column/statistics/geometry/GeospatialStatistics.java: ########## @@ -0,0 +1,247 @@ +/* + * 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.column.statistics.geometry; + +import java.util.Objects; +import org.apache.parquet.Preconditions; +import org.apache.parquet.io.api.Binary; +import org.apache.parquet.schema.LogicalTypeAnnotation; +import org.apache.parquet.schema.PrimitiveType; +import org.locationtech.jts.geom.Geometry; +import org.locationtech.jts.io.ParseException; +import org.locationtech.jts.io.WKBReader; + +/** + * A structure for capturing metadata for estimating the unencoded, + * uncompressed size of geospatial data written. + */ +public class GeospatialStatistics { + + // Metadata that may impact the statistics calculation + private final BoundingBox boundingBox; + private final EdgeInterpolationAlgorithm edgeAlgorithm; + private final GeospatialTypes geospatialTypes; + + /** + * Merge the statistics from another GeospatialStatistics object. + * + * @param other the other GeospatialStatistics object + */ + public void mergeStatistics(GeospatialStatistics other) { + if (other == null) { + return; + } + if (this.boundingBox != null && other.boundingBox != null) { + this.boundingBox.merge(other.boundingBox); + } + if (this.geospatialTypes != null && other.geospatialTypes != null) { + this.geospatialTypes.merge(other.geospatialTypes); + } + } + + /** + * Builder to create a GeospatialStatistics. + */ + public static class Builder { + private BoundingBox boundingBox; + private GeospatialTypes geospatialTypes; + private EdgeInterpolationAlgorithm edgeAlgorithm; + private final WKBReader reader = new WKBReader(); + + /** + * Create a builder to create a GeospatialStatistics. + * For Geometry type, edgeAlgorithm is not required. + */ + public Builder() { + this.boundingBox = new BoundingBox(); + this.geospatialTypes = new GeospatialTypes(); + this.edgeAlgorithm = null; + } + + /** + * Create a builder to create a GeospatialStatistics. + * For Geography type, optional edgeAlgorithm can be set. + */ + public Builder(EdgeInterpolationAlgorithm edgeAlgorithm) { + this.boundingBox = new BoundingBox(); + this.geospatialTypes = new GeospatialTypes(); + this.edgeAlgorithm = edgeAlgorithm; + } + + public void update(Binary value) { + if (value == null) { + return; + } + try { + Geometry geom = reader.read(value.getBytes()); + update(geom); + } catch (ParseException e) { + abort(); + } + } + + private void update(Geometry geom) { + boundingBox.update(geom); + geospatialTypes.update(geom); + } + + public void abort() { + boundingBox.abort(); + geospatialTypes.abort(); + } + + /** + * Build a GeospatialStatistics from the builder. + * + * @return a new GeospatialStatistics object + */ + public GeospatialStatistics build() { + return new GeospatialStatistics(boundingBox, geospatialTypes, edgeAlgorithm); + } + } + + /** + * Create a new GeospatialStatistics builder with the specified CRS. + * + * @param type the primitive type + * @return a new GeospatialStatistics builder + */ + public static GeospatialStatistics.Builder newBuilder(PrimitiveType type) { + LogicalTypeAnnotation logicalTypeAnnotation = type.getLogicalTypeAnnotation(); + if (logicalTypeAnnotation instanceof LogicalTypeAnnotation.GeometryLogicalTypeAnnotation) { + return new GeospatialStatistics.Builder(); + } else if (logicalTypeAnnotation instanceof LogicalTypeAnnotation.GeographyLogicalTypeAnnotation) { + EdgeInterpolationAlgorithm edgeAlgorithm = + ((LogicalTypeAnnotation.GeographyLogicalTypeAnnotation) logicalTypeAnnotation).getEdgeAlgorithm(); + return new GeospatialStatistics.Builder(edgeAlgorithm); + } else { + return noopBuilder(); + } + } + + /** + * Constructs a GeospatialStatistics object with the specified CRS, bounding box, and geospatial types. + * + * @param boundingBox the bounding box for the geospatial data, or null if not applicable, note that + * - The bounding box (bbox) is omitted only if there are no X or Y values. + * - The Z and/or M statistics are omitted only if there are no Z and/or M values, respectively. + * @param geospatialTypes the geospatial types + */ + public GeospatialStatistics( + BoundingBox boundingBox, GeospatialTypes geospatialTypes, EdgeInterpolationAlgorithm edgeAlgorithm) { + this.boundingBox = boundingBox; + this.geospatialTypes = geospatialTypes; + this.edgeAlgorithm = edgeAlgorithm; + } + + /** + * Constructs a GeospatialStatistics object with the specified CRS. + */ + public GeospatialStatistics() { + this(new BoundingBox(), new GeospatialTypes(), null); + } + + /** + * Constructs a GeospatialStatistics object with the specified CRS and edge interpolation algorithm. + * + * @param crs the coordinate reference system + * @param edgeAlgorithm the edge interpolation algorithm + */ + public GeospatialStatistics(String crs, EdgeInterpolationAlgorithm edgeAlgorithm) { + this.boundingBox = new BoundingBox(); + this.geospatialTypes = new GeospatialTypes(); + this.edgeAlgorithm = edgeAlgorithm; + } + + /** Returns the bounding box. */ + public BoundingBox getBoundingBox() { + return boundingBox; + } + + /** Returns the geometry types. */ + public GeospatialTypes getGeospatialTypes() { + return geospatialTypes; + } + + /** + * @return whether the statistics has valid value. + */ + public boolean isValid() { + if (boundingBox == null && geospatialTypes == null) { + return false; + } + return Objects.requireNonNull(this.boundingBox).isValid() + && Objects.requireNonNull(this.geospatialTypes).isValid(); + } + + public void merge(GeospatialStatistics other) { + Preconditions.checkArgument(other != null, "Cannot merge with null GeometryStatistics"); + + if (boundingBox != null && other.boundingBox != null) { + boundingBox.merge(other.boundingBox); Review Comment: I believe @wgtmac is correct here: if either `boundingBox` or `other.boundingBox` is null, we can no longer say anything about the bounding box and so we have to set `this.boundingBox = null;`. It's also a good point that if a file has one row group where we have all nulls, this will clobber useful statistics at the file level if this `merge()` method is used for that purpose. I might recommend ensuring the correct but suboptimal behaviour for this PR and following up to fix that issue if it turns out the `merge()` method is used in this way. -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
