public class HDFSTransactionLogReaderV2 extends Object implements TransactionLogReader
TransactionLogReader
that can read v2 version of Transaction logs. The logs are expected to
have commit markers that indicates the size of the batch of TransactionEdit
s (follows the marker),
that were synced together. If the expected number of TransactionEdit
s are not present then that set of
TransactionEdit
s are discarded.Constructor and Description |
---|
HDFSTransactionLogReaderV2(org.apache.hadoop.io.SequenceFile.Reader reader) |
Modifier and Type | Method and Description |
---|---|
void |
close() |
TransactionEdit |
next()
Returns the next
TransactionEdit from the log file, based on the current position, or null
if the end of the file has been reached. |
TransactionEdit |
next(TransactionEdit reuse)
Populates
reuse with the next TransactionEdit , based on the reader's current position in the
log file. |
public HDFSTransactionLogReaderV2(org.apache.hadoop.io.SequenceFile.Reader reader)
public void close() throws IOException
close
in interface Closeable
close
in interface AutoCloseable
IOException
public TransactionEdit next() throws IOException
TransactionLogReader
TransactionEdit
from the log file, based on the current position, or null
if the end of the file has been reached.next
in interface TransactionLogReader
IOException
public TransactionEdit next(TransactionEdit reuse) throws IOException
TransactionLogReader
reuse
with the next TransactionEdit
, based on the reader's current position in the
log file.next
in interface TransactionLogReader
reuse
- The TransactionEdit
instance to populate with the log entry data.TransactionEdit
instance, or null
if the end of the file has been reached.IOException
- If an error is encountered reading the log data.Copyright © 2018 The Apache Software Foundation. All rights reserved.