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   /*
    * 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 io.netty.util.internal.ObjectUtil;
  
  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.MAX_BLOCK_SIZE;
  
  /**
   * {@link ZstdOptions} holds compressionLevel for
   * Zstd compression.
   */
  public class ZstdOptions implements CompressionOptions {
  
      private final int blockSize;
      private final int compressionLevel;
      private final int maxEncodeSize;
  
      /**
       * Default implementation of {@link ZstdOptions} with{compressionLevel(int)} set to
       * {@link ZstdConstants#DEFAULT_COMPRESSION_LEVEL},{@link ZstdConstants#DEFAULT_BLOCK_SIZE},
       * {@link ZstdConstants#MAX_BLOCK_SIZE}
       */
      static final ZstdOptions DEFAULT = new ZstdOptions(DEFAULT_COMPRESSION_LEVEL, DEFAULT_BLOCK_SIZE, MAX_BLOCK_SIZE);
  
      /**
       * Create a new {@link ZstdOptions}
       *
       * @param  blockSize
       *           is used to calculate the compressionLevel
       * @param  maxEncodeSize
       *           specifies the size of the largest compressed object
       * @param  compressionLevel
       *           specifies the level of the compression
       */
      ZstdOptions(int compressionLevel, int blockSize, int maxEncodeSize) {
          if (!Zstd.isAvailable()) {
              throw new IllegalStateException("zstd-jni is not available", Zstd.cause());
          }
  
          this.compressionLevel = ObjectUtil.checkInRange(compressionLevel,
                  MIN_COMPRESSION_LEVEL, MAX_COMPRESSION_LEVEL, "compressionLevel");
          this.blockSize = ObjectUtil.checkPositive(blockSize, "blockSize");
          this.maxEncodeSize = ObjectUtil.checkPositive(maxEncodeSize, "maxEncodeSize");
      }
  
      public int compressionLevel() {
          return compressionLevel;
      }
  
      public int blockSize() {
          return blockSize;
      }
  
      public int maxEncodeSize() {
          return maxEncodeSize;
      }
  }