Command Pattern in java/groovy

Command pattern encapsulates a request. A command pattern maybe used whenever there is a Sender, Receiver who communicate via a request (let's call it command). Assume, we simulate the game of cricket via a Simulator class which sends commands  to the Batsman objects to play certain shots. Each shot is a command given by the simulator to a batsman.

interface Shot{
public void execute();
}

class CoverDrive implements Shot{

private Batsman batter;

public void execute(){
batter.playCoverDrive()
}
}

class straightDrive implements Shot{

private Batsman batter;

public void execute(){
batter.playStraightDrive();
}
}

class Batsman{

def playCoverDrive(){
println("Cover drive")
}

def playStraightDrive(){
println("Cover drive")
}
}

class BatSimulator{

Shot shot

def play(){
shot.execute()
}
}

// main - groovy script start

def sachin = new Batsman()
def command = new CoverDrive(batter : sachin)
def simulator = new BatSimulator(shot : command)
simulator.play()

Tweet