如何在Apache Beam中以byte[]格式读取文件？

import org.apache.beam.sdk.Pipeline;
import org.apache.beam.sdk.io.FileIO;
import org.apache.beam.sdk.io.fs.MatchResult;
import org.apache.beam.sdk.io.fs.ResourceId;
import org.apache.beam.sdk.options.PipelineOptionsFactory;
import org.apache.beam.sdk.transforms.DoFn;
import org.apache.beam.sdk.transforms.ParDo;
import org.apache.beam.sdk.values.KV;

public class ReadFileAsBytesFn extends DoFn<MatchResult.Metadata, KV<String, byte[]>> {
  @ProcessElement
  public void processElement(ProcessContext c) {
    MatchResult.Metadata metadata = c.element();
    ResourceId resourceId = metadata.resourceId();
    try {
      byte[] fileBytes = IOUtils.toByteArray(resourceId.getInputStream());
      c.output(KV.of(resourceId.toString(), fileBytes));
    } catch (IOException e) {
      // 处理读取文件异常
    }
  }
}

public class ReadFilePipeline {
  public static void main(String[] args) {
    PipelineOptions options = PipelineOptionsFactory.create();
    Pipeline pipeline = Pipeline.create(options);

    pipeline
      .apply(FileIO.match().filepattern("path/to/files/*"))
      .apply(FileIO.readMatches())
      .apply(ParDo.of(new ReadFileAsBytesFn()));

    pipeline.run().waitUntilFinish();
  }
}