com.jagrosh.jdautilities.command

Interface CommandListener

public interface CommandListener

An implementable "Listener" that can be added to a CommandClient and used to handle events relating to Commands.

Author:

John Grosh (jagrosh)

Method Summary

Modifier and Type	Method and Description
default void	onCommand(CommandEvent event, Command command) Called when a Command is triggered by a CommandEvent.
default void	onCommandException(CommandEvent event, Command command, java.lang.Throwable throwable) Called when a Command catches a Throwable during execution.
default void	onCompletedCommand(CommandEvent event, Command command) Called when a Command is triggered by a CommandEvent after it's completed successfully.
default void	onNonCommandMessage(net.dv8tion.jda.core.events.message.MessageReceivedEvent event) Called when a MessageReceivedEvent is caught by the Client Listener's but doesn't correspond to a Command.
default void	onTerminatedCommand(CommandEvent event, Command command) Called when a Command is triggered by a CommandEvent but is terminated before completion.

Method Detail

onCommand

default void onCommand(CommandEvent event,
                       Command command)

Called when a Command is triggered by a CommandEvent.

Parameters:

event - The CommandEvent that triggered the Command

command - The Command that was triggered

onCompletedCommand

default void onCompletedCommand(CommandEvent event,
                                Command command)

Called when a Command is triggered by a CommandEvent after it's completed successfully.

Note that a successfully completed command is one that has not encountered an error or exception. Calls that do face errors should be handled by CommandListener#onCommandException

Parameters:

event - The CommandEvent that triggered the Command

command - The Command that was triggered

onTerminatedCommand

default void onTerminatedCommand(CommandEvent event,
                                 Command command)

Called when a Command is triggered by a CommandEvent but is terminated before completion.

Parameters:

event - The CommandEvent that triggered the Command

command - The Command that was triggered

onNonCommandMessage

default void onNonCommandMessage(net.dv8tion.jda.core.events.message.MessageReceivedEvent event)

Called when a MessageReceivedEvent is caught by the Client Listener's but doesn't correspond to a Command.

In other words, this catches all non-command MessageReceivedEvents allowing you to handle them without implementation of another listener.

Parameters:

event - A MessageReceivedEvent that wasn't used to call a Command

onCommandException

default void onCommandException(CommandEvent event,
                                Command command,
                                java.lang.Throwable throwable)

Called when a Command catches a Throwable during execution.

This doesn't account for exceptions thrown during other pre-checks, and should not be treated as such!

An example of this misconception is via a Category test:

 public class BadCommand extends Command {

      public BadCommand() {
          this.name = "bad";
          this.category = new Category("bad category", event  -> {
              // This will throw a NullPointerException if it's not from a Guild!
              return event.getGuild().getIdLong() == 12345678910111213;
          });
      }

       @Override
      protected void execute(CommandEvent) {
          event.reply("This is a bad command!");
      }

 }

The NullPointerException thrown will not be caught by this method!

Parameters:

event - The CommandEvent that triggered the Command

command - The Command that was triggered

throwable - The Throwable thrown during Command execution