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.record.RecordBatch;
  import org.apache.kafka.common.utils.BufferSupplier;
  import org.apache.kafka.common.utils.ByteBufferOutputStream;
  
  import org.junit.jupiter.api.Test;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.nio.charset.StandardCharsets;
  import java.util.Arrays;
  import java.util.Collections;
  
  import static org.apache.kafka.common.record.CompressionType.ZSTD;
  import static org.junit.jupiter.api.Assertions.assertArrayEquals;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  public class ZstdCompressionTest {
  
      @Test
      public void testCompressionDecompression() throws IOException {
          ZstdCompression.Builder builder = Compression.zstd();
          byte[] data = String.join("", Collections.nCopies(256, "data")).getBytes(StandardCharsets.UTF_8);
  
          for (byte magic : Arrays.asList(RecordBatch.MAGIC_VALUE_V0, RecordBatch.MAGIC_VALUE_V1, RecordBatch.MAGIC_VALUE_V2)) {
              for (int level : Arrays.asList(ZSTD.minLevel(), ZSTD.defaultLevel(), ZSTD.maxLevel())) {
                  ZstdCompression compression = builder.level(level).build();
                  ByteBufferOutputStream bufferStream = new ByteBufferOutputStream(4);
                  try (OutputStream out = compression.wrapForOutput(bufferStream, magic)) {
                      out.write(data);
                      out.flush();
                  }
                  bufferStream.buffer().flip();
  
                  try (InputStream inputStream = compression.wrapForInput(bufferStream.buffer(), magic, BufferSupplier.create())) {
                      byte[] result = new byte[data.length];
                      int read = inputStream.read(result);
                      assertEquals(data.length, read);
                      assertArrayEquals(data, result);
                  }
              }
          }
      }
  
      @Test
      public void testCompressionLevels() {
          ZstdCompression.Builder builder = Compression.zstd();
  
          assertThrows(IllegalArgumentException.class, () -> builder.level(ZSTD.minLevel() - 1));
          assertThrows(IllegalArgumentException.class, () -> builder.level(ZSTD.maxLevel() + 1));
  
          builder.level(ZSTD.minLevel());
          builder.level(ZSTD.maxLevel());
      }
  }
  