"cannot be resolved as a type" Error

[dex]

We are working on making our switch to turn on and off our shooter system, a toggle and are getting an error.

package us.oh.k12.wkw.robot.command;

public class ToggleMotorStateCmd extends CommandBase {
    public ToggleMotorStateCmd(){
        super("ShooterTurnMotorOffCmd");
        this.requires(this.getShooterSystem());
    }

    protected void execute() {
         if (!this.getShooterSystem().isShootMotorOn()) {
             // motor is off, turn it on
             this.getShooterSystem().turnOnShootMotor();
         } else{
             //motor is on, turn it off
             this.getShooterSystem().turnOffShootMotor();
         }
     }
}

In a lot of our other commands we extend CommandBase just fine, but this one is saying "CommandBase cannot be resolved as a type." Let me know if you need more information. Below is the method header of a time when we extend command base and it works.

package us.oh.k12.wkw.robot.command;
public class GathererTurnOnCmd extends CommandBase{
   //code
}

[Patrick Chiang]

"X cannot be resolved as a type" errors are commonly caused by two reasons:
1. Missing import statement, wrong package.
2. Referring to a type that doesn't exist.

If you are using an IDE, there should be a way to automatically remedy this.

Also, doesn't Java make your implement all the methods of the abstract class?

    protected void execute() {
    }

    protected boolean isFinished() {
    }

    protected void end() {
    }

    protected void interrupted() {
    }