findepi commented on code in PR #4537: URL: https://github.com/apache/iceberg/pull/4537#discussion_r889734118
########## core/src/main/java/org/apache/iceberg/puffin/PuffinFormat.java: ########## @@ -0,0 +1,164 @@ +/* + * 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.puffin; + +import io.airlift.compress.Compressor; +import io.airlift.compress.zstd.ZstdCompressor; +import io.airlift.compress.zstd.ZstdDecompressor; +import java.io.IOException; +import java.io.OutputStream; +import java.nio.ByteBuffer; +import java.util.function.Function; +import java.util.stream.Stream; +import javax.annotation.Nullable; +import org.apache.iceberg.relocated.com.google.common.base.Preconditions; +import org.apache.iceberg.relocated.com.google.common.collect.ImmutableTable; +import org.apache.iceberg.relocated.com.google.common.collect.Table; +import org.apache.iceberg.util.ByteBuffers; + +final class PuffinFormat { + private PuffinFormat() { + } + + enum Flag { + FOOTER_PAYLOAD_COMPRESSED(0, 0), + /**/; + + private static final Table<Integer, Integer, Flag> BY_BYTE_AND_BIT = Stream.of(values()) + .collect(ImmutableTable.toImmutableTable(Flag::byteNumber, Flag::bitNumber, Function.identity())); + + private final int byteNumber; + private final int bitNumber; + + Flag(int byteNumber, int bitNumber) { + Preconditions.checkArgument( + 0 <= byteNumber && byteNumber < PuffinFormat.FOOTER_STRUCT_FLAGS_LENGTH, + "Invalid byteNumber"); + Preconditions.checkArgument(0 <= bitNumber && bitNumber < Byte.SIZE, "Invalid bitNumber"); + this.byteNumber = byteNumber; + this.bitNumber = bitNumber; + } + + @Nullable + static Flag fromBit(int byteNumber, int bitNumber) { + return BY_BYTE_AND_BIT.get(byteNumber, bitNumber); + } + + public int byteNumber() { + return byteNumber; + } + + public int bitNumber() { + return bitNumber; + } + } + + static final int FOOTER_START_MAGIC_OFFSET = 0; + static final int FOOTER_START_MAGIC_LENGTH = getMagic().length; + + // "Footer struct" denotes the fixed-length portion of the Footer + static final int FOOTER_STRUCT_PAYLOAD_SIZE_OFFSET = 0; + static final int FOOTER_STRUCT_FLAGS_OFFSET = FOOTER_STRUCT_PAYLOAD_SIZE_OFFSET + 4; + static final int FOOTER_STRUCT_FLAGS_LENGTH = 4; + static final int FOOTER_STRUCT_MAGIC_OFFSET = FOOTER_STRUCT_FLAGS_OFFSET + FOOTER_STRUCT_FLAGS_LENGTH; + static final int FOOTER_STRUCT_LENGTH = FOOTER_STRUCT_MAGIC_OFFSET + getMagic().length; + + static final PuffinCompressionCodec FOOTER_COMPRESSION_CODEC = PuffinCompressionCodec.LZ4; + + static byte[] getMagic() { Review Comment: it's shared between classes and array isn't constant, so i didn't want to share array constant. this is called o(1) times overall though, since each class makes its own trusted copy. -- 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]
