private void write(Checkpoint checkpoint, byte[] buf) throws IOException {
BufferedChecksumStreamOutput output =
new BufferedChecksumStreamOutput(new ByteArrayStreamOutput(buf));
output.writeShort((short) Checkpoint.VERSION);
output.writeInt(checkpoint.getPageNum());
output.writeInt(checkpoint.getFirstUnackedPageNum());
output.writeLong(checkpoint.getFirstUnackedSeqNum());
output.writeLong(checkpoint.getMinSeqNum());
output.writeInt(checkpoint.getElementCount());
output.writeInt((int) output.getChecksum());
}
@Test
public void writeNewReadExisting() throws IOException {
io.write("checkpoint.head", 1, 2, 3, 4, 5);
Checkpoint checkpoint = io.read("checkpoint.head");
assertThat(checkpoint.getPageNum(), is(equalTo(1)));
assertThat(checkpoint.getFirstUnackedPageNum(), is(equalTo(2)));
assertThat(checkpoint.getFirstUnackedSeqNum(), is(equalTo(3L)));
assertThat(checkpoint.getMinSeqNum(), is(equalTo(4L)));
assertThat(checkpoint.getElementCount(), is(equalTo(5)));
}