Object-C同樣沒有提供Queue容器,因此我也自己實踐了一個

#import <Foundation/Foundation.h>

@interface NSQueue : NSObject {
	NSMutableArray* m_array;
}

- (void)enqueue:(id)anObject;
- (id)dequeue;
- (void)clear;

@property (nonatomic, readonly) int count;

@end

#import "NSQueue.h"


@implementation NSQueue

@synthesize count;

- (id)init
{
	if( self=[super init] )
	{
		m_array = [[NSMutableArray alloc] init];
		count = 0;
	}
	return self;
}

- (void)dealloc {
	[m_array release];
	[self dealloc];
    [super dealloc];
}

- (void)enqueue:(id)anObject
{
	[m_array addObject:anObject];
	count = m_array.count;
}
- (id)dequeue
{
    id obj = nil;
    if(m_array.count > 0)
    {
        obj = [[[m_array objectAtIndex:0]retain]autorelease];
        [m_array removeObjectAtIndex:0];
        count = m_array.count;
    }
    return obj;
}

- (void)clear
{
	[m_array removeAllObjects];
        count = 0;
}

@end