ZstdEncoder.java — netty Source File

Source Code

/*
 * Copyright 2021 The Netty Project
 *
 * The Netty Project 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:
 *
 *   https://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 io.netty.handler.codec.compression;

import com.github.luben.zstd.Zstd;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.EncoderException;
import io.netty.handler.codec.MessageToByteEncoder;
import io.netty.util.internal.ObjectUtil;
import java.nio.ByteBuffer;

import static io.netty.handler.codec.compression.ZstdConstants.DEFAULT_COMPRESSION_LEVEL;
import static io.netty.handler.codec.compression.ZstdConstants.MIN_COMPRESSION_LEVEL;
import static io.netty.handler.codec.compression.ZstdConstants.MAX_COMPRESSION_LEVEL;
import static io.netty.handler.codec.compression.ZstdConstants.DEFAULT_BLOCK_SIZE;
import static io.netty.handler.codec.compression.ZstdConstants.DEFAULT_MAX_ENCODE_SIZE;

/**
 *  Compresses a {@link ByteBuf} using the Zstandard algorithm.
 *  See <a href="https://facebook.github.io/zstd">Zstandard</a>.
 */
public final class ZstdEncoder extends MessageToByteEncoder<ByteBuf> {
    // Don't use static here as we want to still allow to load the classes.
    {
        try {
            io.netty.handler.codec.compression.Zstd.ensureAvailability();
        } catch (Throwable throwable) {
            throw new ExceptionInInitializerError(throwable);
        }
    }
    private final int blockSize;
    private final int compressionLevel;
    private final int maxEncodeSize;
    private ByteBuf buffer;

    /**
     * Creates a new Zstd encoder.
     *
     * Please note that if you use the default constructor, the default BLOCK_SIZE and MAX_BLOCK_SIZE
     * will be used. If you want to specify BLOCK_SIZE and MAX_BLOCK_SIZE yourself,
     * please use {@link ZstdEncoder(int,int)} constructor
     */
    public ZstdEncoder() {
        this(DEFAULT_COMPRESSION_LEVEL, DEFAULT_BLOCK_SIZE, DEFAULT_MAX_ENCODE_SIZE);
    }
// ... (142 more lines)