text: /*
   * 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.message;
  
  import org.apache.kafka.common.network.Send;
  import org.apache.kafka.common.protocol.ObjectSerializationCache;
  import org.apache.kafka.common.protocol.RecordsReadable;
  import org.apache.kafka.common.protocol.RecordsWritable;
  import org.apache.kafka.common.protocol.types.Schema;
  import org.apache.kafka.common.protocol.types.Struct;
  import org.apache.kafka.common.record.CompressionType;
  import org.apache.kafka.common.record.MemoryRecords;
  import org.apache.kafka.common.record.MultiRecordsSend;
  import org.apache.kafka.common.record.SimpleRecord;
  import org.apache.kafka.common.requests.ByteBufferChannel;
  import org.junit.Test;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.util.ArrayDeque;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertNull;
  
  public class RecordsSerdeTest {
  
      @Test
      public void testSerdeRecords() throws Exception {
          MemoryRecords records = MemoryRecords.withRecords(CompressionType.NONE,
              new SimpleRecord("foo".getBytes()),
              new SimpleRecord("bar".getBytes()));
  
          SimpleRecordsMessageData message = new SimpleRecordsMessageData()
              .setTopic("foo")
              .setRecordSet(records);
  
          testAllRoundTrips(message);
      }
  
      @Test
      public void testSerdeNullRecords() throws Exception {
          SimpleRecordsMessageData message = new SimpleRecordsMessageData()
              .setTopic("foo");
          assertNull(message.recordSet());
  
          testAllRoundTrips(message);
      }
  
      @Test
      public void testSerdeEmptyRecords() throws Exception {
          SimpleRecordsMessageData message = new SimpleRecordsMessageData()
              .setTopic("foo")
              .setRecordSet(MemoryRecords.EMPTY);
          testAllRoundTrips(message);
      }
  
      private void testAllRoundTrips(SimpleRecordsMessageData message) throws Exception {
          for (short version = SimpleRecordsMessageData.LOWEST_SUPPORTED_VERSION;
               version <= SimpleRecordsMessageData.HIGHEST_SUPPORTED_VERSION;
               version++) {
              testRoundTrip(message, version);
          }
      }
  
      private void testRoundTrip(SimpleRecordsMessageData message, short version) throws IOException {
          ByteBuffer buf = serialize(message, version);
  
          SimpleRecordsMessageData message2 = deserialize(buf.duplicate(), version);
          assertEquals(message, message2);
          assertEquals(message.hashCode(), message2.hashCode());
  
          // Check struct serialization as well
          assertEquals(buf, serializeThroughStruct(message, version));
          SimpleRecordsMessageData messageFromStruct = deserializeThroughStruct(buf.duplicate(), version);
          assertEquals(message, messageFromStruct);
          assertEquals(message.hashCode(), messageFromStruct.hashCode());
      }
  
      private SimpleRecordsMessageData deserializeThroughStruct(ByteBuffer buffer, short version) {
          Schema schema = SimpleRecordsMessageData.SCHEMAS[version];
          Struct struct = schema.read(buffer);
          return new SimpleRecordsMessageData(struct, version);
      }
  
      private SimpleRecordsMessageData deserialize(ByteBuffer buffer, short version) {
          RecordsReadable readable = new RecordsReadable(buffer);
          return new SimpleRecordsMessageData(readable, version);
      }
  
      private ByteBuffer serializeThroughStruct(SimpleRecordsMessageData message, short version) {
          Struct struct = message.toStruct(version);
          ByteBuffer buffer = ByteBuffer.allocate(struct.sizeOf());
          struct.writeTo(buffer);
          buffer.flip();
          return buffer;
      }
  
      private ByteBuffer serialize(SimpleRecordsMessageData message, short version) throws IOException {
          ArrayDeque<Send> sends = new ArrayDeque<>();
          ObjectSerializationCache cache = new ObjectSerializationCache();
          int totalMessageSize = message.size(cache, version);
  
          int recordsSize = message.recordSet() == null ? 0 : message.recordSet().sizeInBytes();
          RecordsWritable writer = new RecordsWritable("0",
              totalMessageSize - recordsSize, sends::add);
          message.write(writer, cache, version);
          writer.flush();
  
          MultiRecordsSend send = new MultiRecordsSend("0", sends);
          ByteBufferChannel channel = new ByteBufferChannel(send.size());
          send.writeTo(channel);
          channel.close();
          return channel.buffer();
      }
  
  }
  