diff --git a/assignments/state_pattern/GumballMachine.java b/assignments/state_pattern/GumballMachine.java new file mode 100644 index 0000000..37ce984 --- /dev/null +++ b/assignments/state_pattern/GumballMachine.java @@ -0,0 +1,93 @@ +package assignments.state_pattern; + +public class GumballMachine { + private GumballMachineState soldOutState; + private GumballMachineState noQuarterState; + private GumballMachineState hasQuarterState; + private GumballMachineState soldState; + private GumballMachineState winnerState; + + private int count = 0; + private GumballMachineState currentState; + + public GumballMachine(int numberGumballs) { + soldOutState = new SoldOutState(this); + noQuarterState = new NoQuarterState(this); + hasQuarterState = new HasQuarterState(this); + soldState = new SoldState(this); + winnerState = new WinnerState(this); + + this.count = numberGumballs; + + currentState = (numberGumballs > 0) ? noQuarterState : soldOutState; + } + + public void setState(GumballMachineState currentState) { + this.currentState = currentState; + } + + public void insertQuarter() { + currentState.insertQuarter(); + } + + public void ejectQuarter() { + currentState.ejectQuarter(); + } + + public void turnCrank() { + currentState.turnCrank(); + currentState.dispense(); + } + + public void releaseBall() { + System.out.println("A gumball comes rolling out the slot..."); + if (count > 0) { + count = count - 1; + } + } + + public int getCount() { + return count; + } + + public GumballMachineState getNoQuarterState() { + return noQuarterState; + } + + public GumballMachineState getHasQuarterState() { + return hasQuarterState; + } + + public GumballMachineState getSoldOutState() { + return soldOutState; + } + + public GumballMachineState getSoldState() { + return soldState; + } + + public GumballMachineState getWinnerState() { + return winnerState; + } + + public void refill(int count) { + this.count += count; + System.out.println("The gumball machine was just refilled; its new count is: " + this.count); + if (currentState == soldOutState) { + currentState = noQuarterState; + } + } + + public String toString() { + StringBuffer result = new StringBuffer(); + result.append("\nMighty Gumball, Inc."); + result.append("\nJava-enabled Standing Gumball Model #2004"); + result.append("\nInventory: " + count + " gumball"); + if (count != 1) { + result.append("s"); + } + result.append("\n"); + result.append("Machine is " + currentState.getStateToString() + "\n"); + return result.toString(); + } +} \ No newline at end of file diff --git a/assignments/state_pattern/GumballMachineState.java b/assignments/state_pattern/GumballMachineState.java new file mode 100644 index 0000000..b6c9156 --- /dev/null +++ b/assignments/state_pattern/GumballMachineState.java @@ -0,0 +1,15 @@ +package assignments.state_pattern; + +//State Interface +//Should showcase actions on the state only +public interface GumballMachineState { + void insertQuarter(); + + void ejectQuarter(); + + void turnCrank(); + + void dispense(); + + String getStateToString(); +} diff --git a/assignments/state_pattern/GumballMachineTestDrive.java b/assignments/state_pattern/GumballMachineTestDrive.java new file mode 100644 index 0000000..003054b --- /dev/null +++ b/assignments/state_pattern/GumballMachineTestDrive.java @@ -0,0 +1,45 @@ +package assignments.state_pattern; + +public class GumballMachineTestDrive { + + public static void main(String[] args) { + GumballMachine gumballMachine = new GumballMachine(10); + + System.out.println(gumballMachine); + + gumballMachine.insertQuarter(); + gumballMachine.turnCrank(); + gumballMachine.insertQuarter(); + gumballMachine.turnCrank(); + + System.out.println(gumballMachine); + + gumballMachine.insertQuarter(); + gumballMachine.turnCrank(); + gumballMachine.insertQuarter(); + gumballMachine.turnCrank(); + + System.out.println(gumballMachine); + + gumballMachine.insertQuarter(); + gumballMachine.turnCrank(); + gumballMachine.insertQuarter(); + gumballMachine.turnCrank(); + + System.out.println(gumballMachine); + + gumballMachine.insertQuarter(); + gumballMachine.turnCrank(); + gumballMachine.insertQuarter(); + gumballMachine.turnCrank(); + + System.out.println(gumballMachine); + + gumballMachine.insertQuarter(); + gumballMachine.turnCrank(); + gumballMachine.insertQuarter(); + gumballMachine.turnCrank(); + + System.out.println(gumballMachine); + } +} diff --git a/assignments/state_pattern/HasQuarterState.java b/assignments/state_pattern/HasQuarterState.java new file mode 100644 index 0000000..541a090 --- /dev/null +++ b/assignments/state_pattern/HasQuarterState.java @@ -0,0 +1,44 @@ +package assignments.state_pattern; + +import java.util.Random; + +public class HasQuarterState implements GumballMachineState { + private Random randomWinner = new Random(System.currentTimeMillis()); + private GumballMachine gumballMachine; + + public HasQuarterState(GumballMachine gumballMachine) { + this.gumballMachine = gumballMachine; + } + + @Override + public void insertQuarter() { + System.out.println("You can't insert another quarter"); + } + + @Override + public void ejectQuarter() { + System.out.println("Quarter returned"); + gumballMachine.setState(gumballMachine.getNoQuarterState()); + } + + @Override + public void turnCrank() { + System.out.println("You turned..."); + int winner = randomWinner.nextInt(10); + if ((winner == 0) && (gumballMachine.getCount() > 1)) { + gumballMachine.setState(gumballMachine.getWinnerState()); + } else { + gumballMachine.setState(gumballMachine.getSoldState()); + } + } + + @Override + public void dispense() { + System.out.println("No gumball dispensed"); + } + + @Override + public String getStateToString() { + return "waiting for turn of crank"; + } +} diff --git a/assignments/state_pattern/NoQuarterState.java b/assignments/state_pattern/NoQuarterState.java new file mode 100644 index 0000000..0d5288e --- /dev/null +++ b/assignments/state_pattern/NoQuarterState.java @@ -0,0 +1,35 @@ +package assignments.state_pattern; + +public class NoQuarterState implements GumballMachineState { + private GumballMachine gumballMachine; + + public NoQuarterState(GumballMachine gumballMachine) { + this.gumballMachine = gumballMachine; + } + + @Override + public void insertQuarter() { + System.out.println("You inserted a quarter"); + gumballMachine.setState(gumballMachine.getHasQuarterState()); + } + + @Override + public void ejectQuarter() { + System.out.println("You haven't inserted a quarter"); + } + + @Override + public void turnCrank() { + System.out.println("You turned, but there's no quarter"); + } + + @Override + public void dispense() { + System.out.println("You need to pay first"); + } + + @Override + public String getStateToString() { + return "waiting for quarter"; + } +} diff --git a/assignments/state_pattern/SoldOutState.java b/assignments/state_pattern/SoldOutState.java new file mode 100644 index 0000000..d9c4554 --- /dev/null +++ b/assignments/state_pattern/SoldOutState.java @@ -0,0 +1,34 @@ +package assignments.state_pattern; + +public class SoldOutState implements GumballMachineState { + private GumballMachine gumballMachine; + + public SoldOutState(GumballMachine gumballMachine) { + this.gumballMachine = gumballMachine; + } + + @Override + public void insertQuarter() { + System.out.println("You can't insert a quarter, the machine is sold out"); + } + + @Override + public void ejectQuarter() { + System.out.println("You can't eject, you haven't inserted a quarter yet"); + } + + @Override + public void turnCrank() { + System.out.println("You turned, but there are no gumballs"); + } + + @Override + public void dispense() { + System.out.println("No gumball dispensed"); + } + + @Override + public String getStateToString() { + return "sold out"; + } +} diff --git a/assignments/state_pattern/SoldState.java b/assignments/state_pattern/SoldState.java new file mode 100644 index 0000000..e7e3d12 --- /dev/null +++ b/assignments/state_pattern/SoldState.java @@ -0,0 +1,40 @@ +package assignments.state_pattern; + +public class SoldState implements GumballMachineState { + private GumballMachine gumballMachine; + + public SoldState(GumballMachine gumballMachine) { + this.gumballMachine = gumballMachine; + } + + @Override + public void insertQuarter() { + System.out.println("Please wait, we're already giving you a gumball"); + } + + @Override + public void ejectQuarter() { + System.out.println("Sorry, you already turned the crank"); + } + + @Override + public void turnCrank() { + System.out.println("Turning twice doesn't get you another gumball!"); + } + + @Override + public void dispense() { + gumballMachine.releaseBall(); + if (gumballMachine.getCount() > 0) { + gumballMachine.setState(gumballMachine.getNoQuarterState()); + } else { + System.out.println("Oops, out of gumballs!"); + gumballMachine.setState(gumballMachine.getSoldOutState()); + } + } + + @Override + public String getStateToString() { + return "dispensing a gumball"; + } +} diff --git a/assignments/state_pattern/WinnerState.java b/assignments/state_pattern/WinnerState.java new file mode 100644 index 0000000..e838cf4 --- /dev/null +++ b/assignments/state_pattern/WinnerState.java @@ -0,0 +1,46 @@ +package assignments.state_pattern; + +public class WinnerState implements GumballMachineState { + private GumballMachine gumballMachine; + + public WinnerState(GumballMachine gumballMachine) { + this.gumballMachine = gumballMachine; + } + + @Override + public void insertQuarter() { + System.out.println("Please wait, we're already giving you a Gumball"); + } + + @Override + public void ejectQuarter() { + System.out.println("Sorry, you already turned the crank"); + } + + @Override + public void turnCrank() { + System.out.println("Turning again doesn't get you another gumball!"); + } + + @Override + public void dispense() { + gumballMachine.releaseBall(); + if (gumballMachine.getCount() <= 0) { + gumballMachine.setState(gumballMachine.getSoldOutState()); + } else { + gumballMachine.releaseBall(); + System.out.println("YOU'RE A WINNER! You got two gumballs for your quarter"); + if (gumballMachine.getCount() > 0) { + gumballMachine.setState(gumballMachine.getNoQuarterState()); + } else { + System.out.println("Oops, out of gumballs!"); + gumballMachine.setState(gumballMachine.getSoldOutState()); + } + } + } + + @Override + public String getStateToString() { + return "despensing two gumballs for your quarter, because YOU'RE A WINNER!"; + } +}