Familiarizing Yourself With Iphone Development Stanford Exercise Whatatoolb

Stanford Exercise 2B - WhatAToolB

Here's my solution and code for this exercise:

WhatAToolB.m

#import 
#import "PolygonShape.h"

void PrintPathInfo() {
 //expand the directory
 NSString *path = [@"~" stringByExpandingTildeInPath];
 NSLog(@"My home folder is at %@", path);
 
 //get the components of the url
 NSArray *folders = [path pathComponents];
 
 //print each component/folder
 for(NSString *element in folders) {
  NSLog(@"%@", element);
 }
}

void PrintProcessInfo() {
 NSString *processName = [[NSProcessInfo processInfo] processName];
 NSInteger processIdentifier = [[NSProcessInfo processInfo] processIdentifier];
 
 //prints the process name and id
 NSLog(@"Process Name: '%@' Process ID: '%i'", processName, processIdentifier);
}

void PrintBookmarkInfo() {
 NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];
 //creates an NSURL object and add it to a NSMutableDictionary object
 [dictionary setValue: [NSURL URLWithString:@"http://www.stanford.edu"] forKey: @"Stanford University"];
 [dictionary setValue: [NSURL URLWithString:@"http://www.apple.com"] forKey: @"Apple"];
 [dictionary setValue: [NSURL URLWithString:@"http://www.cs193p.stanford.edu"] forKey: @"CS193P"];
 [dictionary setValue: [NSURL URLWithString:@"http://www.itunes.stanford.edu"] forKey: @"Stanford on iTunes U"];
 [dictionary setValue: [NSURL URLWithString:@"http://www.stanfordshop.com"] forKey: @"Stanford Mall"];
 
 //iterate
 NSString *key;
 for(key in dictionary) {
  NSString *value = [dictionary objectForKey:key];
  //checks if prefix has "Stanford" word
  if([key hasPrefix: @"Stanford"]) {
   NSLog(@"%@", value);
  }
 }
}

void PrintIntrospectionInfo() {
 //creates an assorted types of objects
 NSString *string = [NSString stringWithFormat:@"Hello World!"];
 NSURL *url = [NSURL URLWithString:@"http://google.com"];
 NSProcessInfo *processInfo = [NSProcessInfo processInfo];
 NSDictionary *dictionary = [NSDictionary dictionary];
 NSMutableString *ms1 = [NSMutableString string];
 [ms1 appendString:@"Hello "];
 [ms1 appendString:@"World!"];
 
 NSMutableArray *array = [NSMutableArray array];
 
 //add to an object array
 [array addObject: string];
 [array addObject: url];
 [array addObject: processInfo];
 [array addObject: dictionary];
 [array addObject: ms1];
 
 //iterate to the object array
 int count = [array count];
 for(int i = 0; i < count; i++) {
  //get the object at the current index
  NSObject *object = [array objectAtIndex: i];
  
  //prints the class name
  NSLog(@"Class name: %@", [object className]);
  
  //check if the object is a member of class NSString
  if([object isMemberOfClass: [NSString class]]) {
   NSLog(@"Is Member of NSString: YES");
  } else {
   NSLog(@"Is Member of NSString: NO");
  }
  
  //check if the object is a kind of NSString class
  if([object isKindOfClass: [NSString class]]) {
   NSLog(@"Is Kind of NSString: YES");
  } else {
   NSLog(@"Is Kind of NSString: NO");
  }
  
  //initialize a lowercaseString selector
  SEL selector = @selector(lowercaseString);
  //check if the object respond to that selector
  if([object respondsToSelector: selector]) {
   NSLog(@"Responds to lowercaseString: YES");
   //perform the method
   NSLog(@"lowercaseString is: %@", [object performSelector: selector]);
  } else {
   NSLog(@"Responds to lowercaseString: NO");
  }
  
  NSLog(@"==================================");
 }
}

void PrintPolygonInfo() {
 NSMutableArray *arrayPoly = [[NSMutableArray alloc] init];
 PolygonShape *shape1 = [[PolygonShape alloc] init];
 [shape1 initWithNumberOfSides:4 minimumNumberOfSides:3 maximumNumberOfSides:7];
 [arrayPoly addObject:shape1];
 NSLog(@"Poly1: %@", shape1);
 
 [shape1 retain];
 [shape1 initWithNumberOfSides:6 minimumNumberOfSides:5 maximumNumberOfSides:9];
 [arrayPoly addObject:shape1];
 NSLog(@"Poly1: %@", shape1);
 
 [shape1 retain];
 [shape1 initWithNumberOfSides:12 minimumNumberOfSides:9 maximumNumberOfSides:12];
 [arrayPoly addObject:shape1];
 NSLog(@"Poly1: %@", shape1);
 
 int count = [arrayPoly count];
 for(int i = 0; i < count; i++) {
  PolygonShape *temp = [arrayPoly objectAtIndex:i];
  [temp setNumberOfSides:10];
 }
 
 [shape1 release];
 [shape1 release];
 [shape1 release];
}

int main (int argc, const char * argv[]) {
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
 
    NSLog(@"Hello, World!");
 
 PrintPathInfo();
 PrintProcessInfo();
 PrintBookmarkInfo();
 PrintIntrospectionInfo();
 PrintPolygonInfo();
 
    [pool drain];
    return 0;
}

PolygonShape.h

//
//  PolygonShape.h
//  WhatAToolB
//
//  Created by edwardlegaspi on 12/16/10.
//  Copyright 2010 Kalidad Business Solutions. All rights reserved.
//

#import 


@interface PolygonShape : NSObject {
 int numberOfSides;
 int minimumNumberOfSides;
 int maximumNumberOfSides;
 float angelInDegrees;
 float angelInRadians;
 NSString *name;
}

@property int numberOfSides;
@property int minimumNumberOfSides;
@property int maximumNumberOfSides;
@property (readonly) float angelInDegrees;
@property (readonly) float angelInRadians;
@property (readonly) NSString *name;

-(id)initWithNumberOfSides:(int)sides minimumNumberOfSides:(int)min maximumNumberOfSides:(int)max;
-(NSString *)description;

@end

PolygonShape.m

//
//  PolygonShape.m
//  WhatAToolB
//
//  Created by edwardlegaspi on 12/16/10.
//  Copyright 2010 Kalidad Business Solutions. All rights reserved.
//

#import "PolygonShape.h"


@implementation PolygonShape

@synthesize numberOfSides;
@synthesize minimumNumberOfSides;
@synthesize maximumNumberOfSides;

-(void)setNumberOfSides:(int)value {
 if(value > minimumNumberOfSides && value < maximumNumberOfSides) {
  numberOfSides = value;
 } else {
  NSLog(@"Invalid number of sides: %d. Must be in the range [%d-%d]", value, minimumNumberOfSides, maximumNumberOfSides);
 }
}

-(void)setMinimumNumberOfSides:(int)value {
 if(value < 2) {
  NSLog(@"Minimum value must be greater than or equal to 2");
 } else {
  minimumNumberOfSides = value;
 }
}

-(void)setMaximumNumberOfSides:(int)value {
 if(value > 12) {
  NSLog(@"Maximum value must be less than or equal to 12");
 } else {
  maximumNumberOfSides = value;
 }
}

-(id)initWithNumberOfSides:(int)sides minimumNumberOfSides:(int)min maximumNumberOfSides:(int)max {
 minimumNumberOfSides = min;
 maximumNumberOfSides = max;
 numberOfSides = sides;
 return self;
}

-(id)init {
 if(self = [super init]) {
  minimumNumberOfSides = 3;
  maximumNumberOfSides = 10;
  numberOfSides = 5;
 }
 return self;
}

-(float)angelInRadians {
 return (M_PI * [self angelInDegrees]) / 180;
}

-(float)angelInDegrees {
 float f = (180 * (numberOfSides - 2) / numberOfSides);
 return f;
}

-(NSString *)name {
 NSString *polyName = [NSString string];
 switch (numberOfSides) {
  case 2:
   polyName = @"Digon";
   break;
  case 3:
   polyName = @"Triangle";
   break;
  case 4:
   polyName = @"Quadrilateral";
   break;
  case 5:
   polyName = @"Pentagon";
   break;
  case 6:
   polyName = @"Hexagon";
   break;
  case 7:
   polyName = @"Heptagon";
   break;
  case 8:
   polyName = @"Octagon";
   break;
  case 9:
   polyName = @"Nonagon";
   break;
  case 10:
   polyName = @"Decagon";
   break;
  case 11:
   polyName = @"Hendecagon";
   break;
  case 12:
   polyName = @"Dodecagon";
   break;
  default:
   break;
 }
 return polyName;
}

-(NSString *)description {
 NSString *d = [NSString stringWithFormat:@"Hello I am a %d-sided polygon (aka a %@) with angels of %f degrees (%f radians).", numberOfSides, [self name], [self angelInDegrees], [self angelInRadians]];
 return d;
}

@end