robocode
Class Robot

java.lang.Object
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  +--robocode._Robot
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        +--robocode.Robot

All Implemented Interfaces:

Runnable

Direct Known Subclasses:

_AdvancedRobot

public class Robot

extends _Robot

implements Runnable

The basic robot class that you will extend to create your own robots.

Please note the following standards will be used:
heading - absolute angle in degrees with 0 facing up the screen, positive clockwise. 0 <= heading < 360.
bearing - relative angle to some object from your robot's heading, positive clockwise. -180 < bearing <= 180
All coordinates are expressed as (x,y).
All coordinates are positive.
The origin (0,0) is at the bottom left of the screen.
Positive x is right.
Positive y is up.

See Also:

robocode.alphaworks.ibm.com, Building your first robot

Field Summary

PrintStream

out The output stream your robot should use to print.

Constructor Summary

Robot()

Method Summary

void	ahead(double distance) Moves your robot forward.
void	back(double distance) Moves your robot backward.
void	doNothing() Do nothing this turn.
void	finalize() Called by the system to 'clean up' after your robot.
void	fire(double power) Fires a bullet.
Bullet	fireBullet(double power) Fires a bullet.
double	getBattleFieldHeight() Get height of the current battlefield.
double	getBattleFieldWidth() Get width of the current battlefield.
double	getEnergy() Returns the robot's current energy
double	getGunCoolingRate() Returns the rate at which the gun will cool down.
double	getGunHeading() Returns gun heading in degrees.
double	getGunHeat() Returns the current heat of the gun.
double	getHeading() Returns the direction the robot is facing, in degrees.
double	getHeight() Returns the height of the robot
String	getName() Returns the robot's name
int	getNumRounds() Returns the number of rounds in the current battle
int	getOthers() Returns how many opponents are left
double	getRadarHeading() Returns radar heading in degrees.
int	getRoundNum() Returns the number of the current round (1 to getNumRounds()) in the battle
long	getTime() Returns the current game time Note: 1 battle consists of multiple rounds Time is reset to 0 at the beginning of every round.
double	getVelocity() Returns the velocity of the robot.
double	getWidth() Returns the width of the robot
double	getX() Returns the X position of the robot.
double	getY() Returns the Y position of the robot.
void	onBulletHit(BulletHitEvent event) This method will be called when one of your bullets hits another robot.
void	onBulletHitBullet(BulletHitBulletEvent event) This method will be called when one of your bullets hits another bullet.
void	onBulletMissed(BulletMissedEvent event) This method will be called when one of your bullets misses (hits a wall).
void	onDeath(DeathEvent event) This method will be called if your robot dies You should override it in your robot if you want to be informed of this event.
void	onHitByBullet(HitByBulletEvent event) This method will be called when your robot is hit by a bullet.
void	onHitRobot(HitRobotEvent event) This method will be called when your robot collides with another robot.
void	onHitWall(HitWallEvent event) This method will be called when your robot collides with a wall.
void	onRobotDeath(RobotDeathEvent event) This method will be called if another robot dies You should override it in your robot if you want to be informed of this event.
void	onScannedRobot(ScannedRobotEvent event) This method will be called when your robot sees another robot.
void	onWin(WinEvent event) This method will be called if your robot wins a battle.
void	resume() Resume the movement you stopped in stop(), if any.
void	run() The main method in every robot.
void	scan() Look for other robots.
void	setAdjustGunForRobotTurn(boolean newAdjustGunForRobotTurn) Sets the gun to automatically turn the opposite way when the robot turns.
void	setAdjustRadarForGunTurn(boolean newAdjustRadarForGunTurn) Sets the radar to automatically turn the opposite way when the gun turns.
void	setAdjustRadarForRobotTurn(boolean newAdjustRadarForRobotTurn) Sets the radar to automatically turn the opposite way when the robot turns.
void	setColors(Color robotColor, Color gunColor, Color radarColor) Call this method to set your robot's colors.
void	stop() Stops all movement, and saves it for a call to resume().
void	stop(boolean overwrite) Stops all movement, and saves it for a call to resume().
void	turnGunLeft(double degrees) Rotates your robot's gun.
void	turnGunRight(double degrees) Rotates your robot's gun.
void	turnLeft(double degrees) Rotates your robot.
void	turnRadarLeft(double degrees) Rotates your robot's radar.
void	turnRadarRight(double degrees) Rotates your robot's radar.
void	turnRight(double degrees) Rotates your robot.

Methods inherited from class robocode._Robot

getBattleNum, getGunCharge, getGunImageName, getLife, getNumBattles, getRadarImageName, getRobotImageName, setGunImageName, setInterruptible, setPeer, setRadarImageName, setRobotImageName

Methods inherited from class java.lang.Object

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

Field Detail

out

public PrintStream out

The output stream your robot should use to print. You can view it by clicking the buttons on the right side of the battle.

Example public void onHitRobot(HitRobotEvent e) { out.println("I hit a robot! My energy: " + getEnergy() + " his energy: " + e.getEnergy()); } System.out will also print to this.

Constructor Detail

Robot

public Robot()

Method Detail

ahead

public void ahead(double distance)

Moves your robot forward. This call executes immediately, and does not return until it is complete. If the robot collides with a wall, the move is complete. If the robot collides with another robot, the move is complete if you are heading toward the other robt.

Example

   ahead(50);
 

Parameters:

distance - The distance to move forward

See Also:

onHitWall(robocode.HitWallEvent), onHitRobot(robocode.HitRobotEvent)

back

public void back(double distance)

Moves your robot backward. This call executes immediately, and does not return until it is complete. If the robot collides with a wall, the move is complete. If the robot collides with another robot, the move is complete if you are heading toward the other robt.

Example

   back(150);
 

Parameters:

distance - The distance to backward

See Also:

onHitWall(robocode.HitWallEvent), onHitRobot(robocode.HitRobotEvent)

getBattleFieldHeight

public double getBattleFieldHeight()

Get height of the current battlefield.

Returns:

The height of the battlefield.

getBattleFieldWidth

public double getBattleFieldWidth()

Get width of the current battlefield.

Returns:

The width of the battlefield.

getHeading

public double getHeading()

Returns the direction the robot is facing, in degrees. The value returned will be between 0 and 360.

Returns:

the direction the robot is facing, in degrees.

getHeight

public double getHeight()

Returns the height of the robot

Returns:

the height of the robot

getName

public String getName()

Returns the robot's name

Returns:

the robot's name

getWidth

public double getWidth()

Returns the width of the robot

Returns:

the width of the robot

getX

public double getX()

Returns the X position of the robot. (0,0) is at the bottom left of the battlefield.

Returns:

the X position of the robot

getY

public double getY()

Returns the Y position of the robot. (0,0) is at the bottom left of the battlefield.

Returns:

the Y position of the robot

run

public void run()

The main method in every robot. Override this to set up your robot's basic behavior.

Example

 // A basic robot that moves around in a square
 public void run() {
   while (true) {
      ahead(100);
      turnRight(90);
   }
 

Specified by:

run in interface Runnable

turnLeft

public void turnLeft(double degrees)

Rotates your robot. This call executes immediately, and does not return until it is complete. Note that the gun and radar will rotate the same amount, as they are attached to the robot.

Example

   turnLeft(90);
 

turnRight

public void turnRight(double degrees)

Rotates your robot. This call executes immediately, and does not return until it is complete. Note that the gun and radar will rotate the same amount, as they are attached to the robot.

Example

   turnRight(90);
 

doNothing

public void doNothing()

Do nothing this turn. This call executes immediately.

finalize

public final void finalize()

Called by the system to 'clean up' after your robot. You may not override this method.

Overrides:

finalize in class Object

fire

public void fire(double power)

Fires a bullet. The valid range for power is .1 to 3. The bullet will travel in the direction the gun is pointing. The bullet will do (4 * power) damage if it hits another robot. If power is greater than 1, it will do an additional 2 * (power - 1) damage. You will get (3 * power) back if you hit the other robot. An event will be generated when the bullet hits a robot, wall, or other bullet. This call executes immediately.

Parameters:

power - The energy given to the bullet, and subtracted from your energy.

See Also:

fireBullet(double), onBulletHit(robocode.BulletHitEvent), onBulletHitBullet(robocode.BulletHitBulletEvent), onBulletMissed(robocode.BulletMissedEvent)

fireBullet

public Bullet fireBullet(double power)

Fires a bullet. This call is exactly like fire(double), but returns the Bullet object you fired. This call executes immediately.

See Also:

fire(double)

getGunCoolingRate

public double getGunCoolingRate()

Returns the rate at which the gun will cool down.

Returns:

the gun cooling rate

See Also:

getGunHeat()

getGunHeading

public double getGunHeading()

Returns gun heading in degrees. This is a value from 0 to 360, where 0 points to the top of the screen.

Returns:

gun heading

getGunHeat

public double getGunHeat()

Returns the current heat of the gun. You cannot fire unless this is 0. (Calls to fire will succeed, but will not actually fire unless getGunHeat() == 0

Returns:

the current gun heat

getNumRounds

public int getNumRounds()

Returns the number of rounds in the current battle

Returns:

the number of rounds in the current battle

getOthers

public int getOthers()

Returns how many opponents are left

Returns:

how many opponents are left

getRadarHeading

public double getRadarHeading()

Returns radar heading in degrees. This is a value from 0 to 360, where 0 points to the top of the screen.

Returns:

radar heading

getRoundNum

public int getRoundNum()

Returns the number of the current round (1 to getNumRounds()) in the battle

Returns:

the number of the current round in the battle

getTime

public long getTime()

Returns the current game time Note: 1 battle consists of multiple rounds Time is reset to 0 at the beginning of every round. getTime() is equivalent to the number of frames displayed this round.

Returns:

the current game time

getVelocity

public double getVelocity()

Returns the velocity of the robot.

Returns:

the velocity of the robot

onBulletHit

public void onBulletHit(BulletHitEvent event)

This method will be called when one of your bullets hits another robot. You should override it in your robot if you want to be informed of this event.

Example

   public void onBulletHit(BulletHitEvent event) {
     out.println("I hit " + event.getName() + "!");
   }
 

Parameters:

event - The event set by the game

See Also:

BulletHitEvent, Event

onBulletHitBullet

public void onBulletHitBullet(BulletHitBulletEvent event)

This method will be called when one of your bullets hits another bullet. You should override it in your robot if you want to be informed of this event.

Example

   public void onBulletHitBullet(BulletHitBulletEvent event) {
     out.println("I hit a bullet fired by " + event.getBullet().getName() + "!");
   }
 

Parameters:

event - The event set by the game

See Also:

BulletHitBulletEvent, Event

onBulletMissed

public void onBulletMissed(BulletMissedEvent event)

This method will be called when one of your bullets misses (hits a wall). You should override it in your robot if you want to be informed of this event.

Example

   public void onBulletHit(BulletMissedEvent event) {
     out.println("Drat, I missed.");
   }
 

Parameters:

event - The event set by the game

See Also:

BulletMissedEvent, Event

onDeath

public void onDeath(DeathEvent event)

This method will be called if your robot dies You should override it in your robot if you want to be informed of this event. Actions will have no effect if called from this section. The intent is to allow you to perform calculations or print something out when you lose.

Parameters:

event - The event set by the game

See Also:

DeathEvent, Event

onHitByBullet

public void onHitByBullet(HitByBulletEvent event)

This method will be called when your robot is hit by a bullet. You should override it in your robot if you want to be informed of this event.

Example

   public void onHitByBullet(HitByBulletEvent event) {
     out.println(event.getRobotName() + " hit me!");
   }
 

Parameters:

event - The event set by the game

See Also:

HitByBulletEvent, Event

onHitRobot

public void onHitRobot(HitRobotEvent event)

This method will be called when your robot collides with another robot. You should override it in your robot if you want to be informed of this event.

Example

   public void onHitRobot(HitRobotEvent event) {
     if (event.getBearing() > -90 && event.getBearing() <= 90)
       back(100);
     else
       ahead(100);
   }

   -- or perhaps, for a more advanced robot --

   public void onHitRobot(HitRobotEvent event) {
     if (event.getBearing() > -90 && event.getBearing() <= 90)
       setBack(100);
     else
       setAhead(100);
   }
 

The angle is relative to your robot's facing... so 0 is straight ahead of you.

This event can be generated if another robot hits you, in which case event.isMyFault() will return false. In this case, you will not be automatically stopped by the game -- but if you continue moving toward the robot you will hit it (and generate another event). If you are moving away, then you won't hit it.

Parameters:

event - The event set by the game

See Also:

HitRobotEvent, Event

onHitWall

public void onHitWall(HitWallEvent event)

This method will be called when your robot collides with a wall. You should override it in your robot if you want to be informed of this event. Note: The wall at the top of the screen is 0 degrees, right is 90 degrees, bottom is 180 degrees, left is 270 degrees. -- but this event is relative to your heading, so: The bearing is such that turnRight(e.getBearing()) will point you perpendicular to the wall.

Example

   public void onHitWall(HitWallEvent event) {
     out.println("Ouch, I hit a wall bearing " + event.getBearing() + " degrees.");
   }
 

Parameters:

event - The event set by the game

See Also:

HitWallEvent, Event

onRobotDeath

public void onRobotDeath(RobotDeathEvent event)

This method will be called if another robot dies You should override it in your robot if you want to be informed of this event.

Parameters:

event - The event set by the game

See Also:

RobotDeathEvent, Event

onScannedRobot

public void onScannedRobot(ScannedRobotEvent event)

This method will be called when your robot sees another robot. You should override it in your robot if you want to be informed of this event. (Almost all robots should override this!) This event will be called automatically if there is a robot in range of your radar.

The bearing is relative to your robot's heading.

Example

   public void onScannedRobot(ScannedRobotEvent event) {
   	// Assuming radar and gun are aligned...
   	if (event.getDistance() < 100)
   		fire(3);
   	else
   		fire(1);
   }
 

Note: The game assists Robots in firing, as follows: If the gun and radar are aligned (and were aligned last turn), and the event is current, and you call fire() before taking any other actions, fire() will fire directly at the robot. In essence, this means that if you can see a robot, and it doesn't move, then fire will hit it. AdvancedRobots will NOT be assisted in this manner, and are expected to examine the event to determine if fire() would hit. (i.e. you are spinning your gun around, but by the time you get the event, your gun is 5 degrees past the robot)

Parameters:

event - The event set by the game

See Also:

ScannedRobotEvent, Event

onWin

public void onWin(WinEvent event)

This method will be called if your robot wins a battle. You can do a victory dance here.

Parameters:

event - The event set by the game

See Also:

WinEvent, Event

resume

public void resume()

Resume the movement you stopped in stop(), if any. This call executes immediately, and does not return until it is complete.

See Also:

stop()

scan

public void scan()

Look for other robots. This method is called automatically by the game, as long as you are moving, turning, turning your gun, or turning your radar. There are 2 reasons to call scan() manually: 1 - You want to scan after you stop moving 2 - You want to interrupt the onScannedRobot event. This is more likely. If you are in onScannedRobot, and call scan(), and you still see a robot, then the system will interrupt your onScannedRobot event immediately and start it from the top. This call executes immediately. Scan will cause onScannedRobot(robocode.ScannedRobotEvent) to be called if you see a robot.

See Also:

onScannedRobot(robocode.ScannedRobotEvent), ScannedRobotEvent

setAdjustGunForRobotTurn

public void setAdjustGunForRobotTurn(boolean newAdjustGunForRobotTurn)

Sets the gun to automatically turn the opposite way when the robot turns. Ok, so this needs some explanation: The gun is mounted on the robot. So, normally, if the robot turns 90 degrees to the right, then the gun will turn with it.

To compensate for this, you can call setAdjustGunForRobotTurn(true). When this is set, the gun will automatically turn in the opposite direction, so that it "stays still" when the robot turns.

Example, assuming both the robot and gun start out facing up (0 degrees):

   setAdjustGunForRobotTurn(false); // This is the default
   turnRight(90);
   // At this point, both the robot and gun are facing right (90 degrees);
   turnLeft(90);
   // Both are back to 0 degrees

   -- or --

   setAdjustGunForRobotTurn(true);
   turnRight(90);
   // At this point, the robot is facting right (90 degrees), but the gun is still facing up.
   turnLeft(90);
   // Both are back to 0 degrees.
  

Note: The gun compensating this way does count as "turning the gun". See setAdjustRadarForGunTurn(boolean) for details.

See Also:

setAdjustRadarForGunTurn(boolean)

setAdjustRadarForGunTurn

public void setAdjustRadarForGunTurn(boolean newAdjustRadarForGunTurn)

Sets the radar to automatically turn the opposite way when the gun turns. Make sure you understand how setAdjustGunForRobotTurn(boolean) works before reading on...

Ok, so now you understand setAdjustGunForRobotTurn(boolean) right?

Just like the gun is mounted on the robot, the radar is mounted on the gun. So, normally, if the gun turns 90 degrees to the right, then the radar will turn with it.

To compensate for this (if you like), you can call setAdjustRadarForGunTurn(true). When this is set, the radar will automatically turn in the opposite direction, so that it "stays still" when the gun turns (in relation to the body, as of 0.97).

Example, assuming both the radar and gun start out facing up (0 degrees):

   setAdjustRadarForGunTurn(false); // This is the default
   turnGunRight(90);
   // At this point, both the radar and gun are facing right (90 degrees);

   -- or --

   setAdjustRadarForGunTurn(true);
   turnGunRight(90);
   // At this point, the gun is facing right (90 degrees), but the radar is still facing up.

 

Note: Calling setAdjustRadarForGunTurn will automatically call setAdjustRadarForRobotTurn with the same value, unless you have already called it yourself. This behavior is primarily for backward compatibility with older Robocode robots.

See Also:

setAdjustRadarForRobotTurn(boolean), setAdjustGunForRobotTurn(boolean)

setColors

public void setColors(Color robotColor,
                      Color gunColor,
                      Color radarColor)

Call this method to set your robot's colors. You may only call this method one time per battle. A null indicates the default (blue-ish) color.

 Example:
   // Don't forget to import java.awt.Color at the top...
   import java.awt.Color;
 
   public void run() {
     setColors(Color.black,Color.red,new Color(150,0,150));
   }
 

Parameters:

robotColor - Your robot's color

gunColor - Your robot's gun color

radarColor - Your robot's radar color

See Also:

Color

stop

public void stop()

Stops all movement, and saves it for a call to resume(). If there is already movement saved from a previous stop, this will have no effect. This method is equivalent to stop(false); This call executes immediately.

See Also:

stop(boolean), resume()

stop

public void stop(boolean overwrite)

Stops all movement, and saves it for a call to resume(). If there is already movement saved from a previous stop, you can overwrite it by calling stop(true). This call executes immediately.

See Also:

resume(), stop()

turnGunLeft

public void turnGunLeft(double degrees)

Rotates your robot's gun. This call executes immediately, and does not return until it is complete.

Example

   turnGunLeft(90);
 

turnGunRight

public void turnGunRight(double degrees)

Rotates your robot's gun. This call executes immediately, and does not return until it is complete.

Example

   turnGunRight(90);
 

turnRadarLeft

public void turnRadarLeft(double degrees)

Rotates your robot's radar. This call executes immediately, and does not return until it is complete. Many robots will use the turnGun functions instead... the radar will rotate when the gun rotates, and you will probably want your gun facing in the same direction anyway.

Example

   turnRadarLeft(90);
 

turnRadarRight

public void turnRadarRight(double degrees)

Rotates your robot's radar. This call executes immediately, and does not return until it is complete. Many robots will use the turnGun functions instead... the radar will rotate when the gun rotates, and you will probably want your gun facing in the same direction anyway.

Example

   turnRadarRight(90);
 

getEnergy

public double getEnergy()

Returns the robot's current energy

Returns:

the robot's energy

setAdjustRadarForRobotTurn

public void setAdjustRadarForRobotTurn(boolean newAdjustRadarForRobotTurn)

Sets the radar to automatically turn the opposite way when the robot turns.

The radar is mounted on the gun, which is mounted on the robot. So, normally, if the robot turns 90 degrees to the right, the gun turns, as does the radar.0

To compensate for this (if you like), you can call setAdjustRadarForRobotTurn(true). When this is set, the radar will automatically turn in the opposite direction, so that it "stays still" when the body turns.

Example, assuming the robot, gun, and radar all start out facing up (0 degrees):

   setAdjustRadarForRobotTurn(false); // This is the default
   turnRight(90);
   // At this point, all three are facing right (90 degrees);

   -- or --

   setAdjustRadarForRobotTurn(true);
   turnRight(90);
   // At this point, the robot and gun are facing right (90 degrees), but the radar is still facing up.

 

See Also:

setAdjustGunForRobotTurn(boolean), setAdjustRadarForGunTurn(boolean)