content: /*
   * 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.kafka.common.compress;
  
  import org.apache.kafka.common.KafkaException;
  import org.apache.kafka.common.record.CompressionType;
  import org.apache.kafka.common.record.RecordBatch;
  import org.apache.kafka.common.utils.BufferSupplier;
  import org.apache.kafka.common.utils.ByteBufferOutputStream;
  import org.apache.kafka.common.utils.ChunkedBytesStream;
  
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.nio.ByteBuffer;
  import java.util.Objects;
  
  import static org.apache.kafka.common.record.CompressionType.LZ4;
  
  public class Lz4Compression implements Compression {
  
      private final int level;
  
      private Lz4Compression(int level) {
          this.level = level;
      }
  
      @Override
      public CompressionType type() {
          return LZ4;
      }
  
      @Override
      public OutputStream wrapForOutput(ByteBufferOutputStream buffer, byte messageVersion) {
          try {
              return new Lz4BlockOutputStream(buffer, level, messageVersion == RecordBatch.MAGIC_VALUE_V0);
          } catch (Throwable e) {
              throw new KafkaException(e);
          }
      }
  
      @Override
      public InputStream wrapForInput(ByteBuffer inputBuffer, byte messageVersion, BufferSupplier decompressionBufferSupplier) {
          try {
              return new ChunkedBytesStream(
                      new Lz4BlockInputStream(inputBuffer, decompressionBufferSupplier, messageVersion == RecordBatch.MAGIC_VALUE_V0),
                      decompressionBufferSupplier, decompressionOutputSize(), true);
          } catch (Throwable e) {
              throw new KafkaException(e);
          }
      }
  
      @Override
      public int decompressionOutputSize() {
          // Lz4BlockInputStream uses an internal intermediate buffer to store decompressed data. The size
          // of this buffer is based on legacy implementation based on skipArray introduced in
          // https://github.com/apache/kafka/pull/6785
          return 2 * 1024; // 2KB
      }
  
      @Override
      public boolean equals(Object o) {
          if (this == o) return true;
          if (o == null || getClass() != o.getClass()) return false;
          Lz4Compression that = (Lz4Compression) o;
          return level == that.level;
      }
  
      @Override
      public int hashCode() {
          return Objects.hash(level);
      }
  
      public static class Builder implements Compression.Builder<Lz4Compression> {
          private int level = LZ4.defaultLevel();
  
          public Builder level(int level) {
              if (level < LZ4.minLevel() || LZ4.maxLevel() < level) {
                  throw new IllegalArgumentException("lz4 doesn't support given compression level: " + level);
              }
  
              this.level = level;
              return this;
          }
  
          @Override
          public Lz4Compression build() {
              return new Lz4Compression(level);
          }
      }
  }
  