aihuaxu commented on code in PR #11415: URL: https://github.com/apache/iceberg/pull/11415#discussion_r1893471194
########## core/src/main/java/org/apache/iceberg/variants/SerializedObject.java: ########## @@ -0,0 +1,198 @@ +/* + * 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.iceberg.variants; + +import java.nio.ByteBuffer; +import java.nio.ByteOrder; +import java.util.Iterator; +import org.apache.iceberg.relocated.com.google.common.annotations.VisibleForTesting; +import org.apache.iceberg.relocated.com.google.common.base.Preconditions; +import org.apache.iceberg.util.Pair; + +class SerializedObject extends Variants.SerializedValue implements VariantObject { + private static final int OFFSET_SIZE_MASK = 0b1100; + private static final int OFFSET_SIZE_SHIFT = 2; + private static final int FIELD_ID_SIZE_MASK = 0b110000; + private static final int FIELD_ID_SIZE_SHIFT = 4; + private static final int IS_LARGE = 0b1000000; + + static SerializedObject from(SerializedMetadata metadata, byte[] bytes) { + return from(metadata, ByteBuffer.wrap(bytes).order(ByteOrder.LITTLE_ENDIAN), bytes[0]); + } + + static SerializedObject from(SerializedMetadata metadata, ByteBuffer value, int header) { + Preconditions.checkArgument( + value.order() == ByteOrder.LITTLE_ENDIAN, "Unsupported byte order: big endian"); + Variants.BasicType basicType = VariantUtil.basicType(header); + Preconditions.checkArgument( + basicType == Variants.BasicType.OBJECT, "Invalid object, basic type: " + basicType); + return new SerializedObject(metadata, value, header); + } + + private final SerializedMetadata metadata; + private final ByteBuffer value; + private final int fieldIdSize; + private final int fieldIdListOffset; + private final Integer[] fieldIds; + private final int offsetSize; + private final int offsetListOffset; + private final int dataOffset; + private final VariantValue[] values; + + private SerializedObject(SerializedMetadata metadata, ByteBuffer value, int header) { + this.metadata = metadata; + this.value = value; + this.offsetSize = 1 + ((header & OFFSET_SIZE_MASK) >> OFFSET_SIZE_SHIFT); + this.fieldIdSize = 1 + ((header & FIELD_ID_SIZE_MASK) >> FIELD_ID_SIZE_SHIFT); + int numElementsSize = ((header & IS_LARGE) == IS_LARGE) ? 4 : 1; + int numElements = + VariantUtil.readLittleEndianUnsigned(value, Variants.HEADER_SIZE, numElementsSize); + this.fieldIdListOffset = Variants.HEADER_SIZE + numElementsSize; + this.fieldIds = new Integer[numElements]; + this.offsetListOffset = fieldIdListOffset + (numElements * fieldIdSize); + this.dataOffset = offsetListOffset + ((1 + numElements) * offsetSize); + this.values = new VariantValue[numElements]; + } + + @VisibleForTesting + int numElements() { + return fieldIds.length; + } + + SerializedMetadata metadata() { + return metadata; + } + + Iterable<Pair<String, Integer>> fields() { + return () -> + new Iterator<>() { + private int index = 0; + + @Override + public boolean hasNext() { + return index < fieldIds.length; + } + + @Override + public Pair<String, Integer> next() { + Pair<String, Integer> next = Pair.of(metadata.get(id(index)), index); + index += 1; + return next; + } + }; + } + + public Iterable<String> fieldNames() { + return () -> + new Iterator<>() { + private int index = 0; + + @Override + public boolean hasNext() { + return index < fieldIds.length; + } + + @Override + public String next() { + int id = id(index); + index += 1; + return metadata.get(id); + } + }; + } + + private int id(int index) { + if (null == fieldIds[index]) { + fieldIds[index] = + VariantUtil.readLittleEndianUnsigned( + value, fieldIdListOffset + (index * fieldIdSize), fieldIdSize); + } + return fieldIds[index]; + } + + @Override + public VariantValue get(String name) { + // keys are ordered lexicographically by the name + int index = VariantUtil.find(fieldIds.length, name, pos -> metadata.get(id(pos))); + + if (index < 0) { + return null; + } + + if (null == values[index]) { + int offset = + VariantUtil.readLittleEndianUnsigned( + value, offsetListOffset + (index * offsetSize), offsetSize); + int next = + VariantUtil.readLittleEndianUnsigned( + value, offsetListOffset + ((1 + index) * offsetSize), offsetSize); + values[index] = + Variants.from(metadata, VariantUtil.slice(value, dataOffset + offset, next - offset)); Review Comment: There is an inconsistency between writer and reader here. Here we are assuming that offsets are in order but the writer in Spark would have different order. For an object, since we access and write the values 1234, "joe", and "smith" in order, the offsets will be 3, 0, 7, 13. With that, if we slice the buffer by (0, 7), we get the wrong result. ``` { "id": 1234, "first_name": "joe", "last_name": "smith" } ``` -- 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: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org
