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:

  • Field Details

    • NONE_AVAILABLE

      public static final int NONE_AVAILABLE
      See Also:

    • 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 Details

    • 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