StandardErrorRecordWriter implements RecordWriter<P> { @Override public void writeRecords(Batch<P> batch) { for (Record<P> record : batch) { System.err.println(record.getPayload().toString()); } }  @Override void writeRecords(Batch<P> batch);  }
@Test public void testRecordPayloadWriting() { writer.writeRecords(new Batch<>(record)); assertThat(systemErr.getLog()).isEqualTo(PAYLOAD + LINE_SEPARATOR); }