Package org.apache.flink.streaming.api.operators

Class InputSelection

java.lang.Object

org.apache.flink.streaming.api.operators.InputSelection

All Implemented Interfaces:

Serializable

@PublicEvolving
public final class InputSelection
extends Object
implements Serializable

Describe the input selection that stream operators want to read records.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	InputSelection.Builder	Utility class for creating InputSelection.

Field Summary

Fields

Modifier and Type	Field	Description
static InputSelection	ALL	The InputSelection instance which indicates to select all inputs.
static InputSelection	FIRST	The InputSelection instance which indicates to select the first input.
static int	NONE_AVAILABLE
static InputSelection	SECOND	The InputSelection instance which indicates to select the second input.

Method Summary

Modifier and Type	Method	Description
boolean	areAllInputsSelected()	Tests if all inputs are selected.
boolean	equals(Object o)
int	fairSelectNextIndex(long availableInputsMask, int lastReadInputIndex)	Fairly select one of the available inputs for reading.
static int	fairSelectNextIndex(long inputMask, long availableInputsMask, int lastReadInputIndex)	Fairly select one of the available inputs for reading.
int	fairSelectNextIndexOutOf2(int availableInputsMask, int lastReadInputIndex)	Fairly select one of the two inputs for reading.
static int	fairSelectNextIndexOutOf2(int selectionMask, int availableInputsMask, int lastReadInputIndex)	Fairly select one of the two inputs for reading.
long	getInputMask()
boolean	isInputSelected(int inputId)	Tests if the input specified by inputId is selected.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

NONE_AVAILABLE

public static final int NONE_AVAILABLE

See Also:

Constant Field Values

ALL

public static final InputSelection ALL

The InputSelection instance which indicates to select all inputs.

FIRST

public static final InputSelection FIRST

The InputSelection instance which indicates to select the first input.

SECOND

public static final InputSelection SECOND

The InputSelection instance which indicates to select the second input.

Method Detail

getInputMask

public long getInputMask()

isInputSelected

public boolean isInputSelected(int inputId)

Tests if the input specified by inputId is selected.

Parameters:

inputId - The input id, see the description of inputId in InputSelection.Builder.select(int).

Returns:

true if the input is selected, false otherwise.

areAllInputsSelected

public boolean areAllInputsSelected()

Tests if all inputs are selected.

Returns:

true if the input mask equals -1, false otherwise.

fairSelectNextIndexOutOf2

public int fairSelectNextIndexOutOf2(int availableInputsMask,
                                     int lastReadInputIndex)

Fairly select one of the two inputs for reading. When inputMask includes two inputs and both inputs are available, alternately select one of them. Otherwise, select the available one of inputMask, or return NONE_AVAILABLE to indicate no input is selected.

Note that this supports only two inputs for performance reasons.

Parameters:

availableInputsMask - The mask of all available inputs.

lastReadInputIndex - The index of last read input.

Returns:

the index of the input for reading or NONE_AVAILABLE (if inputMask is empty or the inputs in inputMask are unavailable).

fairSelectNextIndexOutOf2

public static int fairSelectNextIndexOutOf2(int selectionMask,
                                            int availableInputsMask,
                                            int lastReadInputIndex)

Fairly select one of the two inputs for reading. When inputMask includes two inputs and both inputs are available, alternately select one of them. Otherwise, select the available one of inputMask, or return NONE_AVAILABLE to indicate no input is selected.

Note that this supports only two inputs for performance reasons.

Parameters:

selectionMask - The mask of inputs that are selected. Note -1 for this is interpreted as all of the 32 inputs are available.

availableInputsMask - The mask of all available inputs.

lastReadInputIndex - The index of last read input.

Returns:

the index of the input for reading or NONE_AVAILABLE (if inputMask is empty or the inputs in inputMask are unavailable).

fairSelectNextIndex

public int fairSelectNextIndex(long availableInputsMask,
                               int lastReadInputIndex)

Fairly select one of the available inputs for reading.

Parameters:

availableInputsMask - The mask of all available inputs. Note -1 for this is interpreted as all of the 32 inputs are available.

lastReadInputIndex - The index of last read input.

Returns:

the index of the input for reading or NONE_AVAILABLE (if inputMask is empty or the inputs in inputMask are unavailable).

fairSelectNextIndex

public static int fairSelectNextIndex(long inputMask,
                                      long availableInputsMask,
                                      int lastReadInputIndex)

Fairly select one of the available inputs for reading.

Parameters:

inputMask - The mask of inputs that are selected. Note -1 for this is interpreted as all of the 32 inputs are available.

availableInputsMask - The mask of all available inputs. Note -1 for this is interpreted as all of the 32 inputs are available.

lastReadInputIndex - The index of last read input.

Returns:

the index of the input for reading or NONE_AVAILABLE (if inputMask is empty or the inputs in inputMask are unavailable).

equals

public boolean equals(Object o)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object