Sample Java -> Objective-C translation for CS132 pages 109-118

Page110Listing1.m

Duck* duck = [[MallardDuck alloc] init];

Page110Listing2.m

Duck* duck;

if(picnic) {
  duck = [[MallardDuck alloc] init];
} else if(hunting) {
  duck = [[DecoyDuck alloc] init];
} else if(inBathTub) {
	duck = [[RubberDuck alloc] init];
}

Page112Listing1.m

-(Pizza*) orderPizza
{
  Pizza* pizza = [[Pizza alloc] init];

	[pizza prepare];
	[pizza bake];
	[pizza cut];
	[pizza box];
	return pizza;
}

Page112Listing2.m

-(Pizza*) orderPizza:(NSString* type)
{
  Pizza* pizza = [[Pizza alloc] init];

	if([type isEqualToString:@"cheese"]) {
		pizza = [[CheesePizza alloc] init];
	} else if([type isEqualToString:@"greek"]) {
	    pizza = [[GreekPizza alloc] init];
	} else if([type isEqualToString:@"pepperoni"]) {
		pizza = [[PepperoniPizza alloc] init];
	}

	[pizza prepare];
	[pizza bake];
	[pizza cut];
	[pizza box];
	return pizza;
}

Page113Listing1.m

-(Pizza*) orderPizza:(NSString* type)
{
  Pizza* pizza;

	if([type isEqualToString:@"cheese"]) {
		pizza = [[CheesePizza alloc] init];
//	} else if([type isEqualToString:@"greek"]) {
//	    pizza = [[GreekPizza alloc] init];
	} else if([type isEqualToString:@"pepperoni"]) {
		pizza = [[PepperoniPizza alloc] init];
	} else if([type isEqualToString:@"clam"]) {
		pizza = [[ClamPizza alloc] init];
	} else if([type isEqualToString:@"veggie"]) {
		pizza = [[VeggiePizza alloc] init];
	}

	[pizza prepare];
	[pizza bake];
	[pizza cut];
	[pizza box];
	return pizza;
}

Page115Listing1.m

@implementation SimplePizzaFactory
-(Pizza*) createPizza(NSString* type)
{
  Pizza* pizza = nil;

	if([type isEqualToString:@"cheese"]) {
		pizza = [[CheesePizza alloc] init];
	} else if([type isEqualToString:@"pepperoni"]) {
		pizza = [[PepperoniPizza alloc] init];
	} else if([type isEqualToString:@"clam"]) {
		pizza = [[ClamPizza alloc] init];
	} else if([type isEqualToString:@"veggie"]) {
		pizza = [[VeggiePizza alloc] init];
	}
	return pizza;	
}
@end

//More idiomatic Objective-C

@implementation SimplePizzaFactory
-(Pizza*) createPizza(NSString* type)
{
	NSDictionary* pizzaTypes = @{	@"cheese":	[CheesePizza class],
					@"pepperoni":	[PepperoniPizza class],
					@"clam":	[ClamPizza class],
					@"veggie":	[VeggiePizza class] };

	Class pizzaClass = [pizzaTypes objectForKey:type];
	Pizza* pizza = [[pizzaClass alloc] init];
	return pizza;	
}
@end

Page116Listing1.m

@interface PizzaStore : NSObject
@property (strong, readwrite) SimplePizzaFactory* factory;
@end

@implementation PizzaStore
-(id)initWithFactory:(SimplePizzaFactory* factory)
{
	self = [super init];
	if(self)
	{
		[self setFactory:factory];
	}
	return self;
}

-(Pizza*) orderPizza:(NSString* type)
{
	Pizza* pizza;

	pizza = [factory createPizza:type];

	[pizza prepare];
	[pizza bake];
	[pizza cut];
	[pizza box];
	return pizza;

}

// other methods here
@end