Package edu.wpi.first.wpilibj.command

Class Scheduler

java.lang.Object
edu.wpi.first.wpilibj.command.Scheduler
public final class Scheduler
extends java.lang.Object
The Scheduler is a singleton which holds the top-level running commands. It is in charge of both calling the command's run() method and to make sure that there are no two commands with conflicting requirements running.

It is fine if teams wish to take control of the Scheduler themselves, all that needs to be done is to call Scheduler.getInstance().run() often to have Commands function correctly. However, this is already done for you if you use the CommandBased Robot template.

See Also:
Command

  • Method Summary

    Modifier and Type Method Description
    void add​(Command command)
    Adds the command to the Scheduler.
    void disable()
    Disable the command scheduler.
    void enable()
    Enable the command scheduler.
    static Scheduler getInstance()
    Returns the Scheduler, creating it if one does not exist.
    void removeAll()
    Removes all commands.
    void run()
    Runs a single iteration of the loop.

    Methods inherited from class java.lang.Object

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

  • Method Details

    • getInstance

      public static Scheduler getInstance()
      Returns the Scheduler, creating it if one does not exist.
      Returns:
      the Scheduler

    • add

      public void add​(Command command)
      Adds the command to the Scheduler. This will not add the Command immediately, but will instead wait for the proper time in the run() loop before doing so. The command returns immediately and does nothing if given null.

      Adding a Command to the Scheduler involves the Scheduler removing any Command which has shared requirements.

      Parameters:
      command - the command to add

    • run

      public void run() throws java.lang.Exception
      Runs a single iteration of the loop. This method should be called often in order to have a functioning Command system. The loop has five stages:
      1. Poll the Buttons
      2. Execute/Remove the Commands
      3. Send values to SmartDashboard
      4. Add Commands
      5. Add Defaults
      Throws:
      java.lang.Exception

    • removeAll

      public void removeAll()
      Removes all commands.

    • disable

      public void disable()
      Disable the command scheduler.

    • enable

      public void enable()
      Enable the command scheduler.