Enum Class Worker.State

java.lang.Object
java.lang.Enum<Worker.State>
javafx.concurrent.Worker.State
All Implemented Interfaces:
Serializable, Comparable<Worker.State>, Constable
Enclosing interface:
Worker<V>
public static enum Worker.State extends Enum<Worker.State>

The state of a Worker. The state transitions in a Worker are very well defined. All Workers begin in the READY state. In some circumstances, a Worker might be scheduled for execution before it is actually executed. In such cases, it is sometimes useful to know when the Worker has been SCHEDULED separately from when it is RUNNING. However even in cases where the Worker is executed immediately, the Worker will temporarily enter the SCHEDULED state before entering the RUNNING state. That is, the transition is always from READY to SCHEDULED to RUNNING (unless of course the Worker in cancelled).

A Worker which runs but is never cancelled can only end up in one of two states, either SUCCEEDED or FAILED. It only enters FAILED if an exception was thrown during the execution of the Worker. A Worker may be cancelled when READY, SCHEDULED, or RUNNING, in which case the final status will be CANCELLED. When a Worker is cancelled in one of these circumstances it will transition immediately to the CANCELLED state.

A reusable Worker will transition from CANCELLED, SUCCEEDED or FAILED back to READY. From that point the normal state transitions are again followed.

Since:
JavaFX 2.0

  • Nested Class Summary

    Nested classes/interfaces declared in class java.lang.Enum

    Enum.EnumDesc<E extends Enum<E>>

  • Enum Constant Summary

    Enum Constants
    Enum Constant
    Description
    CANCELLED
    Indicates that this Worker has been cancelled via the Worker.cancel() method.
    FAILED
    Indicates that this Worker has failed, usually due to some unexpected condition having occurred.
    READY
    Indicates that the Worker has not yet been executed and is ready to be executed, or that it has been reinitialized.
    RUNNING
    Indicates that this Worker is running.
    SCHEDULED
    Indicates that the Worker has been scheduled for execution, but that it is not currently running.
    SUCCEEDED
    Indicates that this Worker has completed successfully, and that there is a valid result ready to be read from the value property.

  • Method Summary

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

    Methods declared in class java.lang.Enum

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

    Methods declared in class java.lang.Object

    getClass, notify, notifyAll, wait, wait, wait

  • Enum Constant Details

    • READY

      public static final Worker.State READY
      Indicates that the Worker has not yet been executed and is ready to be executed, or that it has been reinitialized. This is the default initial state of the Worker.

    • SCHEDULED

      public static final Worker.State SCHEDULED
      Indicates that the Worker has been scheduled for execution, but that it is not currently running. This might be because the Worker is waiting for a thread in a thread pool to become available before it can start running.

    • RUNNING

      public static final Worker.State RUNNING
      Indicates that this Worker is running. This is set just immediately prior to the Worker actually doing its first bit of work.

    • SUCCEEDED

      public static final Worker.State SUCCEEDED
      Indicates that this Worker has completed successfully, and that there is a valid result ready to be read from the value property.

    • CANCELLED

      public static final Worker.State CANCELLED
      Indicates that this Worker has been cancelled via the Worker.cancel() method.

    • FAILED

      public static final Worker.State FAILED
      Indicates that this Worker has failed, usually due to some unexpected condition having occurred. The exception can be retrieved from the exception property.

  • Method Details

    • values

      public static Worker.State[] values()
      Returns an array containing the constants of this enum class, in the order they are declared.
      Returns:
      an array containing the constants of this enum class, in the order they are declared

    • valueOf

      public static Worker.State valueOf(String name)
      Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (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 class has no constant with the specified name
      NullPointerException - if the argument is null