/**
* Tests appending and reading to make sure data is written and the data read is consistent with
* the data written.
*
* @throws IOException
*/
@Test
public void basicWriteAndReadTest() throws IOException {
String segmentName = "log_current";
LogSegment segment = getSegment(segmentName, STANDARD_SEGMENT_SIZE, true);
try {
assertEquals(
"Name of segment is inconsistent with what was provided", segmentName, segment.getName());
assertEquals(
"Capacity of segment is inconsistent with what was provided",
STANDARD_SEGMENT_SIZE,
segment.getCapacityInBytes());
assertEquals(
"Start offset is not equal to header size",
LogSegment.HEADER_SIZE,
segment.getStartOffset());
int writeSize = 100;
byte[] buf = TestUtils.getRandomBytes(3 * writeSize);
long writeStartOffset = segment.getStartOffset();
// append with buffer
int written = segment.appendFrom(ByteBuffer.wrap(buf, 0, writeSize));
assertEquals("Size written did not match size of buffer provided", writeSize, written);
assertEquals(
"End offset is not as expected", writeStartOffset + writeSize, segment.getEndOffset());
readAndEnsureMatch(segment, writeStartOffset, Arrays.copyOfRange(buf, 0, writeSize));
// append with channel
segment.appendFrom(
Channels.newChannel(
new ByteBufferInputStream(ByteBuffer.wrap(buf, writeSize, writeSize))),
writeSize);
assertEquals(
"End offset is not as expected",
writeStartOffset + 2 * writeSize,
segment.getEndOffset());
readAndEnsureMatch(
segment, writeStartOffset + writeSize, Arrays.copyOfRange(buf, writeSize, 2 * writeSize));
// use writeFrom
segment.writeFrom(
Channels.newChannel(
new ByteBufferInputStream(ByteBuffer.wrap(buf, 2 * writeSize, writeSize))),
segment.getEndOffset(),
writeSize);
assertEquals(
"End offset is not as expected",
writeStartOffset + 3 * writeSize,
segment.getEndOffset());
readAndEnsureMatch(
segment,
writeStartOffset + 2 * writeSize,
Arrays.copyOfRange(buf, 2 * writeSize, buf.length));
readAndEnsureMatch(segment, writeStartOffset, buf);
// check file size and end offset (they will not match)
assertEquals(
"End offset is not equal to the cumulative bytes written",
writeStartOffset + 3 * writeSize,
segment.getEndOffset());
assertEquals(
"Size in bytes is not equal to size of the file",
STANDARD_SEGMENT_SIZE,
segment.sizeInBytes());
// ensure flush doesn't throw any errors.
segment.flush();
// close and reopen segment and ensure persistence.
segment.close();
segment = new LogSegment(segmentName, new File(tempDir, segmentName), metrics);
segment.setEndOffset(writeStartOffset + buf.length);
readAndEnsureMatch(segment, writeStartOffset, buf);
} finally {
closeSegmentAndDeleteFile(segment);
}
}
/**
* Appends random data of size {@code size} to given {@code segment}.
*
* @param segment the {@link LogSegment} to append data to.
* @param size the size of the data that should be appended.
* @return the data that was appended.
* @throws IOException
*/
private byte[] appendRandomData(LogSegment segment, int size) throws IOException {
byte[] buf = TestUtils.getRandomBytes(size);
segment.appendFrom(ByteBuffer.wrap(buf));
return buf;
}