co.cask.cdap.messaging.store

Class AbstractPayloadTable

java.lang.Object

co.cask.cdap.messaging.store.AbstractPayloadTable

All Implemented Interfaces:

PayloadTable, Closeable, AutoCloseable

Direct Known Subclasses:

LevelDBPayloadTable

public abstract class AbstractPayloadTable
extends Object
implements PayloadTable

Contains common logic for implementation of PayloadTable.

Nested Class Summary

Nested classes/interfaces inherited from interface co.cask.cdap.messaging.store.PayloadTable

PayloadTable.Entry

Constructor Summary

Constructors

Constructor and Description
AbstractPayloadTable()

Method Summary

Modifier and Type	Method and Description
co.cask.cdap.api.dataset.lib.CloseableIterator<PayloadTable.Entry>	fetch(TopicMetadata metadata, long transactionWritePointer, MessageId messageId, boolean inclusive, int limit) Fetches entries from the payload table under the given topic, starting from the given MessageId.
protected abstract void	persist(Iterator<RawPayloadTableEntry> tableEntries) Store the RawPayloadTableEntrys persistently.
protected abstract co.cask.cdap.api.dataset.lib.CloseableIterator<RawPayloadTableEntry>	read(byte[] startRow, byte[] stopRow, int limit) Read the RawPayloadTableEntrys given a key range.
void	store(Iterator<? extends PayloadTable.Entry> entries) Stores a list of entries to the payload table under the given topic.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.io.Closeable

close

Constructor Detail

AbstractPayloadTable

public AbstractPayloadTable()

Method Detail

persist

protected abstract void persist(Iterator<RawPayloadTableEntry> tableEntries)
                         throws IOException

Store the RawPayloadTableEntrys persistently.

Parameters:

tableEntries - Iterator of RawPayloadTableEntrys

Throws:

IOException - thrown if there was an error while storing the entries

read

protected abstract co.cask.cdap.api.dataset.lib.CloseableIterator<RawPayloadTableEntry> read(byte[] startRow,
                                                                                             byte[] stopRow,
                                                                                             int limit)
                                                                                      throws IOException

Read the RawPayloadTableEntrys given a key range.

Parameters:

startRow - start row prefix

stopRow - stop row prefix

limit - maximum number of messages to read

Returns:

CloseableIterator of RawPayloadTableEntrys

Throws:

IOException - thrown if there was an error while trying to read the entries from the table

store

public void store(Iterator<? extends PayloadTable.Entry> entries)
           throws IOException

Description copied from interface: PayloadTable

Stores a list of entries to the payload table under the given topic.

Specified by:

store in interface PayloadTable

Parameters:

entries - a list of entries to store. This method guarantees each PayloadTable.Entry will be consumed right away, hence it is safe for the Iterator to reuse the same PayloadTable.Entry instance

Throws:

IOException

fetch

public co.cask.cdap.api.dataset.lib.CloseableIterator<PayloadTable.Entry> fetch(TopicMetadata metadata,
                                                                                long transactionWritePointer,
                                                                                MessageId messageId,
                                                                                boolean inclusive,
                                                                                int limit)
                                                                         throws IOException

Description copied from interface: PayloadTable

Fetches entries from the payload table under the given topic, starting from the given MessageId.

Specified by:

fetch in interface PayloadTable

Parameters:

metadata - TopicMetadata of the topic to fetch from

transactionWritePointer - transaction write pointer

messageId - message Id to start from

inclusive - true to include the entry identified by the given MessageId as the first message

limit - maximum number of entries to fetch

Returns:

a CloseableIterator of entries

Throws:

IOException