io.debezium.connector.mysql

Class BlockingReader

java.lang.Object

io.debezium.connector.mysql.BlockingReader

All Implemented Interfaces:

Reader

Direct Known Subclasses:

TimedBlockingReader

public class BlockingReader
extends Object
implements Reader

A component that blocks doing nothing until the connector task is stopped

Author:

Peter Goransson

Nested Class Summary

Nested classes/interfaces inherited from interface io.debezium.connector.mysql.Reader

Reader.State

Field Summary

Fields

Modifier and Type	Field and Description
protected org.slf4j.Logger	logger
private Metronome	metronome
private String	name
private String	runningLogMessage
private AtomicReference<Reader.State>	state
private AtomicReference<Runnable>	uponCompletion

Constructor Summary

Constructors

Constructor and Description
BlockingReader(String name, String runningLogMessage)

Method Summary

Modifier and Type	Method and Description
String	name() Get the name of this reader.
List<org.apache.kafka.connect.source.SourceRecord>	poll() Does nothing until the connector task is shut down, but regularly returns control back to Connect in order for being paused if requested.
void	start() Start the reader and return immediately.
Reader.State	state() Get the current state of this reader.
void	stop() Stop the reader from running and transition to the Reader.State.STOPPING state until all remaining records are consumed, at which point its state transitions to Reader.State.STOPPED.
void	uponCompletion(Runnable handler) Set the function that should be called when this reader transitions from the Reader.State.STOPPING to Reader.State.STOPPED state, which is after all generated records have been consumed via the poll method.

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.debezium.connector.mysql.Reader

destroy, initialize

Field Detail

logger

protected final org.slf4j.Logger logger

uponCompletion

private final AtomicReference<Runnable> uponCompletion

state

private final AtomicReference<Reader.State> state

metronome

private final Metronome metronome

name

private final String name

runningLogMessage

private final String runningLogMessage

Constructor Detail

BlockingReader

public BlockingReader(String name,
                      String runningLogMessage)

Method Detail

poll

public List<org.apache.kafka.connect.source.SourceRecord> poll()
                                                        throws InterruptedException

Does nothing until the connector task is shut down, but regularly returns control back to Connect in order for being paused if requested.

Specified by:

poll in interface Reader

Returns:

the list of source records that may or may not be empty; or null when there will be no more records because the reader has completely Reader.State.STOPPED.

Throws:

InterruptedException - if this thread is interrupted while waiting for more records

state

public Reader.State state()

Description copied from interface: Reader

Get the current state of this reader.

Specified by:

state in interface Reader

Returns:

the state; never null

uponCompletion

public void uponCompletion(Runnable handler)

Description copied from interface: Reader

Set the function that should be called when this reader transitions from the Reader.State.STOPPING to Reader.State.STOPPED state, which is after all generated records have been consumed via the poll method.

This method should only be called while the reader is in the Reader.State.STOPPED state.

Specified by:

uponCompletion in interface Reader

Parameters:

handler - the function; may not be null

start

public void start()

Description copied from interface: Reader

Start the reader and return immediately. Once started, the SourceRecords generated by the reader can be obtained by periodically calling Reader.poll() until that method returns null.

This method does nothing if it is already running.

Specified by:

start in interface Reader

stop

public void stop()

Description copied from interface: Reader

Stop the reader from running and transition to the Reader.State.STOPPING state until all remaining records are consumed, at which point its state transitions to Reader.State.STOPPED.

Specified by:

stop in interface Reader

name

public String name()

Description copied from interface: Reader

Get the name of this reader.

Specified by:

name in interface Reader

Returns:

the reader's name; never null