how to check the getter and setter?

[sing1006]

im new in objective c.i have come out with the getter and setter but not sure is correct or not.
.h

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController

@property(nonatomic, retain) NSString *myText;
@property(nonatomic, copy) NSNumber *opacity;
@property(nonatomic, assign) id delegate;

@end

.m

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

@synthesize myText;
@synthesize opacity;
@synthesize delegate;


//getter
-(NSString*)myText{
    return myText;
}
-(NSNumber*)opacity{

    return opacity;
}

-(id)delegate{
    return delegate;
}


//setter
-(void)setMyText:(NSString *)_myText{

    if(myText!=_myText){
    [myText release];
    myText=[_myText retain];

    }
}

-(void)setOpacity:(NSNumber *)_opacity{
    if (opacity!=_opacity) {
        [opacity release];
        opacity=[_opacity copy];
    }
}

-(void)setDelegate:(id)_delegate{
    delegate=_delegate;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.
}

@end