org.apache.flink.api.connector.source

Enum Boundedness

java.lang.Object

java.lang.Enum<Boundedness>

org.apache.flink.api.connector.source.Boundedness

All Implemented Interfaces:

Serializable, Comparable<Boundedness>

@Public
public enum Boundedness
extends Enum<Boundedness>

The boundedness of a stream. A stream could either be "bounded" (a stream with finite records) or "unbounded" (a stream with infinite records).

Enum Constant Summary

Enum Constants

Enum Constant and Description
BOUNDED A BOUNDED stream is a stream with finite records.
CONTINUOUS_UNBOUNDED A CONTINUOUS_UNBOUNDED stream is a stream with infinite records.

Method Summary

Modifier and Type	Method and Description
static Boundedness	valueOf(String name) Returns the enum constant of this type with the specified name.
static Boundedness[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

BOUNDED

public static final Boundedness BOUNDED

A BOUNDED stream is a stream with finite records.

In the context of sources, a BOUNDED stream expects the source to put a boundary of the records it emits. Such boundaries could be number of records, number of bytes, elapsed time, and so on. Such indication of how to bound a stream is typically passed to the sources via configurations. When the sources emit a BOUNDED stream, Flink may leverage this property to do specific optimizations in the execution.

Unlike unbounded streams, the bounded streams are usually order insensitive. That means the source implementations may not have to keep track of the event times or watermarks. Instead, a higher throughput would be preferred.

CONTINUOUS_UNBOUNDED

public static final Boundedness CONTINUOUS_UNBOUNDED

A CONTINUOUS_UNBOUNDED stream is a stream with infinite records.

In the context of sources, an infinite stream expects the source implementation to run without an upfront indication to Flink that they will eventually stop. The sources may eventually be terminated when users cancel the jobs or some source-specific condition is met.

A CONTINUOUS_UNBOUNDED stream may also eventually stop at some point. But before that happens, Flink always assumes the sources are going to run forever.

Method Detail

values

public static Boundedness[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (Boundedness c : Boundedness.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static Boundedness valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null