### Question:
FileRecords extends AbstractRecords implements Closeable { public FileRecords read(int position, int size) throws IOException { if (position < 0) throw new IllegalArgumentException("Invalid position: " + position); if (size < 0) throw new IllegalArgumentException("Invalid size: " + size); final int end; if (this.start + position + size < 0) end = sizeInBytes(); else end = Math.min(this.start + position + size, sizeInBytes()); return new FileRecords(file, channel, this.start + position, end, true); } FileRecords(File file,
                       FileChannel channel,
                       int start,
                       int end,
                       boolean isSlice); @Override int sizeInBytes(); File file(); FileChannel channel(); ByteBuffer readInto(ByteBuffer buffer, int position); FileRecords read(int position, int size); int append(MemoryRecords records); void flush(); void close(); boolean delete(); void trim(); void setFile(File file); void renameTo(File f); int truncateTo(int targetSize); @Override Records downConvert(byte toMagic, long firstOffset); @Override long writeTo(GatheringByteChannel destChannel, long offset, int length); LogOffsetPosition searchForOffsetWithSize(long targetOffset, int startingPosition); TimestampAndOffset searchForTimestamp(long targetTimestamp, int startingPosition, long startingOffset); TimestampAndOffset largestTimestampAfter(int startingPosition); @Override Iterable<FileChannelRecordBatch> batches(); static FileRecords open(File file,
                                   boolean mutable,
                                   boolean fileAlreadyExists,
                                   int initFileSize,
                                   boolean preallocate); static FileRecords open(File file,
                                   boolean fileAlreadyExists,
                                   int initFileSize,
                                   boolean preallocate); static FileRecords open(File file, boolean mutable); static FileRecords open(File file);  }### Answer:
@Test public void testRead() throws IOException { FileRecords read = fileRecords.read(0, fileRecords.sizeInBytes()); TestUtils.checkEquals(fileRecords.batches(), read.batches()); List<RecordBatch> items = batches(read); RecordBatch second = items.get(1); read = fileRecords.read(second.sizeInBytes(), fileRecords.sizeInBytes()); assertEquals("Try a read starting from the second message", items.subList(1, 3), batches(read)); read = fileRecords.read(second.sizeInBytes(), second.sizeInBytes()); assertEquals("Try a read of a single message starting from the second message", Collections.singletonList(second), batches(read)); }