org.apache.hive.hcatalog.streaming

Interface TransactionBatch

public interface TransactionBatch

Represents a set of Transactions returned by Hive. Supports opening, writing to and commiting/aborting each transaction. The interface is designed to ensure transactions in a batch are used up sequentially. Multiple transaction batches can be used (initialized with separate RecordWriters) for concurrent streaming

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	TransactionBatch.TxnState

Method Summary

Methods

Modifier and Type	Method and Description
void	abort() Abort the currently open transaction
void	beginNextTransaction() Activate the next available transaction in the current transaction batch
void	close() Close the TransactionBatch
void	commit() Commit the currently open transaction
TransactionBatch.TxnState	getCurrentTransactionState() get state of current transaction
Long	getCurrentTxnId() Get Id of currently open transaction
void	heartbeat() Issues a heartbeat to hive metastore on the current and remaining txn ids to keep them from expiring
int	remainingTransactions() Remaining transactions are the ones that are not committed or aborted or open.
void	write(byte[] record) Write record using RecordWriter
void	write(Collection<byte[]> records) Write records using RecordWriter

Method Detail

beginNextTransaction

void beginNextTransaction()
                          throws StreamingException,
                                 InterruptedException

Activate the next available transaction in the current transaction batch

Throws:

StreamingException - if not able to switch to next Txn

InterruptedException - if call in interrupted

getCurrentTxnId

Long getCurrentTxnId()

Get Id of currently open transaction

Returns:

transaction id

getCurrentTransactionState

TransactionBatch.TxnState getCurrentTransactionState()

get state of current transaction

commit

void commit()
            throws StreamingException,
                   InterruptedException

Commit the currently open transaction

Throws:

StreamingException - if there are errors committing

InterruptedException - if call in interrupted

abort

void abort()
           throws StreamingException,
                  InterruptedException

Abort the currently open transaction

Throws:

StreamingException - if there are errors

InterruptedException - if call in interrupted

remainingTransactions

int remainingTransactions()

Remaining transactions are the ones that are not committed or aborted or open. Current open transaction is not considered part of remaining txns.

Returns:

number of transactions remaining this batch.

write

void write(byte[] record)
           throws StreamingException,
                  InterruptedException

Write record using RecordWriter

Parameters:

record - the data to be written

Throws:

StreamingException - if there are errors when writing

InterruptedException - if call in interrupted

write

void write(Collection<byte[]> records)
           throws StreamingException,
                  InterruptedException

Write records using RecordWriter

Throws:

StreamingException - if there are errors when writing

InterruptedException - if call in interrupted

heartbeat

void heartbeat()
               throws StreamingException

Issues a heartbeat to hive metastore on the current and remaining txn ids to keep them from expiring

Throws:

StreamingException - if there are errors

close

void close()
           throws StreamingException,
                  InterruptedException

Close the TransactionBatch

Throws:

StreamingException - if there are errors closing batch

InterruptedException - if call in interrupted