Configuration conf = new Configuration();
    FileSystem fs = FileSystem.getLocal(conf);
    Path seqFilePath = new Path("/path/to/your/sequence-file");

    {
      // 打印出sequence file的key和value的类型
      SequenceFile.Reader reader = new SequenceFile.Reader(fs, seqFilePath, conf);
      Writable key = (Writable) reader.getKeyClass().newInstance();
      Writable value = (Writable) reader.getValueClass().newInstance();
      while (reader.next(key, value)) {
        System.out.println("Key type: " + key.getClass());
        System.out.println("Value type: " + value.getClass());
        break;
      }
      reader.close();
    }

    {
      // 打印出sequence file的内容
      SequenceFile.Reader reader = new SequenceFile.Reader(fs, seqFilePath), conf);
      BooleanWritable keyObj = new BooleanWritable();
      Text valueObj = new Text();
      while (reader.next(keyObj, valueObj)) {
        System.out.println(keyObj.get() + ": " + valueObj);
      }
      reader.close();
    }

<dependencies>
  <dependency>
    <groupId>org.apache.hadoop</groupId>
    <artifactId>hadoop-common</artifactId>
    <version>3.2.1</version>
  </dependency>
  <dependency>
    <groupId>org.apache.hadoop</groupId>
    <artifactId>hadoop-client</artifactId>
    <version>3.2.1</version>
  </dependency>
  <dependency>
    <groupId>org.apache.hadoop</groupId>  
    <artifactId>hadoop-hdfs</artifactId>
    <version>3.2.1</version>
  </dependency>
</dependencies>