org.apache.flink.streaming.connectors.wikiedits

Class WikipediaEditsSource

java.lang.Object

org.apache.flink.api.common.functions.AbstractRichFunction

org.apache.flink.streaming.api.functions.source.RichSourceFunction<WikipediaEditEvent>

org.apache.flink.streaming.connectors.wikiedits.WikipediaEditsSource

All Implemented Interfaces:

Serializable, Function, RichFunction, SourceFunction<WikipediaEditEvent>

Deprecated.

This class is based on the SourceFunction API, which is due to be removed. Use the new Source API instead.

@Deprecated
public class WikipediaEditsSource
extends RichSourceFunction<WikipediaEditEvent>

This class is a SourceFunction that reads WikipediaEditEvent instances from the IRC channel #en.wikipedia.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.flink.streaming.api.functions.source.SourceFunction

SourceFunction.SourceContext<T>

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_CHANNEL Deprecated. IRC channel to join.
static String	DEFAULT_HOST Deprecated. Hostname of the server to connect to.
static int	DEFAULT_PORT Deprecated. Port of the server to connect to.

Constructor Summary

Constructors

Constructor and Description
WikipediaEditsSource() Deprecated. Creates a source reading WikipediaEditEvent instances from the IRC channel #en.wikipedia.
WikipediaEditsSource(String host, int port, String channel) Deprecated. Creates a source reading WikipediaEditEvent instances from the specified IRC channel.

Method Summary

Modifier and Type	Method and Description
void	cancel() Deprecated. Cancels the source.
void	run(SourceFunction.SourceContext<WikipediaEditEvent> ctx) Deprecated. Starts the source.

Methods inherited from class org.apache.flink.api.common.functions.AbstractRichFunction

close, getIterationRuntimeContext, getRuntimeContext, open, setRuntimeContext

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.flink.api.common.functions.RichFunction

open

Field Detail

DEFAULT_HOST

public static final String DEFAULT_HOST

Deprecated.

Hostname of the server to connect to.

See Also:

Constant Field Values

DEFAULT_PORT

public static final int DEFAULT_PORT

Deprecated.

Port of the server to connect to.

See Also:

Constant Field Values

DEFAULT_CHANNEL

public static final String DEFAULT_CHANNEL

Deprecated.

IRC channel to join.

See Also:

Constant Field Values

Constructor Detail

WikipediaEditsSource

public WikipediaEditsSource()

Deprecated.

Creates a source reading WikipediaEditEvent instances from the IRC channel #en.wikipedia.

This creates a separate Thread for the IRC connection.

WikipediaEditsSource

public WikipediaEditsSource(String host,
                            int port,
                            String channel)

Deprecated.

Creates a source reading WikipediaEditEvent instances from the specified IRC channel.

In most cases, you want to use the default WikipediaEditsSource(java.lang.String, int, java.lang.String) constructor. This constructor is meant to be used only if there is a problem with the default constructor.

Parameters:

host - The IRC server to connect to.

port - The port of the IRC server to connect to.

channel - The channel to join. Messages not matching the expected format will be ignored.

Method Detail

run

public void run(SourceFunction.SourceContext<WikipediaEditEvent> ctx)
         throws Exception

Deprecated.

Description copied from interface: SourceFunction

Starts the source. Implementations use the SourceFunction.SourceContext to emit elements. Sources that checkpoint their state for fault tolerance should use the checkpoint lock to ensure consistency between the bookkeeping and emitting the elements.

Sources that implement CheckpointedFunction must lock on the checkpoint lock checkpoint lock (using a synchronized block) before updating internal state and emitting elements, to make both an atomic operation.

Refer to the top-level class docs for an example.

Parameters:

ctx - The context to emit elements to and for accessing locks.

Throws:

Exception

cancel

public void cancel()

Deprecated.

Description copied from interface: SourceFunction

Cancels the source. Most sources will have a while loop inside the SourceFunction.run(SourceContext) method. The implementation needs to ensure that the source will break out of that loop after this method is called.

A typical pattern is to have an "volatile boolean isRunning" flag that is set to false in this method. That flag is checked in the loop condition.

In case of an ungraceful shutdown (cancellation of the source operator, possibly for failover), the thread that calls SourceFunction.run(SourceContext) will also be interrupted) by the Flink runtime, in order to speed up the cancellation (to ensure threads exit blocking methods fast, like I/O, blocking queues, etc.). The interruption happens strictly after this method has been called, so any interruption handler can rely on the fact that this method has completed (for example to ignore exceptions that happen after cancellation).

During graceful shutdown (for example stopping a job with a savepoint), the program must cleanly exit the SourceFunction.run(SourceContext) method soon after this method was called. The Flink runtime will NOT interrupt the source thread during graceful shutdown. Source implementors must ensure that no thread interruption happens on any thread that emits records through the SourceContext from the SourceFunction.run(SourceContext) method; otherwise the clean shutdown may fail when threads are interrupted while processing the final records.

Because the SourceFunction cannot easily differentiate whether the shutdown should be graceful or ungraceful, we recommend that implementors refrain from interrupting any threads that interact with the SourceContext at all. You can rely on the Flink runtime to interrupt the source thread in case of ungraceful cancellation. Any additionally spawned threads that directly emit records through the SourceContext should use a shutdown method that does not rely on thread interruption.