001// Copyright (c) FIRST and other WPILib contributors. 002// Open Source Software; you can modify and/or share it under the terms of 003// the WPILib BSD license file in the root directory of this project. 004 005package edu.wpi.first.wpilibj2.command; 006 007import java.util.Set; 008 009/** 010 * A class used internally to wrap commands while overriding a specific method; all other methods 011 * will call through to the wrapped command. 012 * 013 * <p>The rules for command compositions apply: command instances that are passed to it cannot be 014 * added to any other composition or scheduled individually, and the composition requires all 015 * subsystems its components require. 016 */ 017public abstract class WrapperCommand extends Command { 018 protected final Command m_command; 019 020 /** 021 * Wrap a command. 022 * 023 * @param command the command being wrapped. Trying to directly schedule this command or add it to 024 * a composition will throw an exception. 025 */ 026 @SuppressWarnings("this-escape") 027 protected WrapperCommand(Command command) { 028 CommandScheduler.getInstance().registerComposedCommands(command); 029 m_command = command; 030 // copy the wrapped command's name 031 setName(command.getName()); 032 } 033 034 /** The initial subroutine of a command. Called once when the command is initially scheduled. */ 035 @Override 036 public void initialize() { 037 m_command.initialize(); 038 } 039 040 /** The main body of a command. Called repeatedly while the command is scheduled. */ 041 @Override 042 public void execute() { 043 m_command.execute(); 044 } 045 046 /** 047 * The action to take when the command ends. Called when either the command finishes normally, or 048 * when it interrupted/canceled. 049 * 050 * <p>Do not schedule commands here that share requirements with this command. Use {@link 051 * #andThen(Command...)} instead. 052 * 053 * @param interrupted whether the command was interrupted/canceled 054 */ 055 @Override 056 public void end(boolean interrupted) { 057 m_command.end(interrupted); 058 } 059 060 /** 061 * Whether the command has finished. Once a command finishes, the scheduler will call its end() 062 * method and un-schedule it. 063 * 064 * @return whether the command has finished. 065 */ 066 @Override 067 public boolean isFinished() { 068 return m_command.isFinished(); 069 } 070 071 /** 072 * Specifies the set of subsystems used by this command. Two commands cannot use the same 073 * subsystem at the same time. If the command is scheduled as interruptible and another command is 074 * scheduled that shares a requirement, the command will be interrupted. Else, the command will 075 * not be scheduled. If no subsystems are required, return an empty set. 076 * 077 * <p>Note: it is recommended that user implementations contain the requirements as a field, and 078 * return that field here, rather than allocating a new set every time this is called. 079 * 080 * @return the set of subsystems that are required 081 */ 082 @Override 083 public Set<Subsystem> getRequirements() { 084 return m_command.getRequirements(); 085 } 086 087 /** 088 * Whether the given command should run when the robot is disabled. Override to return true if the 089 * command should run when disabled. 090 * 091 * @return whether the command should run when the robot is disabled 092 */ 093 @Override 094 public boolean runsWhenDisabled() { 095 return m_command.runsWhenDisabled(); 096 } 097 098 @Override 099 public InterruptionBehavior getInterruptionBehavior() { 100 return m_command.getInterruptionBehavior(); 101 } 102}