RHCache (Updated 2017)

RHCache is a simple in-memory LRU cache. It evicts objects based on an LRU algorithm and optional time-to-live and time-to-idle properties. Like NSCache, RHCache is a mutable collection with an API similar to NSDictionary. This is a simple fork of the original project, adding support for Cocoapods and Objective-C Generics.

RHCache objects have the following features:

• Least recently used objects are evicted from the cache when the count limit is exceeded. LRU eviction is disabled when the countLimit property is 0 (the default value).
• Objects are evicted when their time-to-live is exceeded. Time-to-live is based on when the object was initially added to the cache. Time-to-live eviction is disabled when the timeToLive property is 0 (the default value).
• Objects are evicted when their time-to-idle is exceeded. Time-to-idle is based on the last time an object was retrieved from the cache. Time-to-idle eviction is disabled when the timeToIdle property is 0 (the default value).
• The cache is thread-safe, so you can add, remove, and query items in the cache from different threads without having to lock the cache yourself.

How To Use

Just #import the RHCache.h header file and use the initializer that supports the eviction features you need. The following example creates a cache with a limit of 1000 objects, a time-to-live of 10 minutes and a time-to-idle of 5 minutes. RHCache now supports Objective-C generics, meaning you can give it a key type and value type. This is especially handy for interoperability with Swift.

#import RHCache.h
RHCache <NSString *, NSNumber *> * cache = [RHCache cacheWithCountLimit: 1000 timeToLive: 600 timeToIdle: 300];

[cache setObject: @1 forKey: @"One"];
[cache setObject: @2 forKey: @"Two"];

NSNumber * one = [cache objectForKey: @"One"];
NSNumber * two = [cache objectForKey: @"Two"];

Installation

The original static library had no support for dependency managers. However, I've converted it into a framework and written a Podspec now. Therefore, the standard deal applies, add it to your podfile:

platform :osx, '10.13'
use_frameworks!

target 'YourProject' do
	pod 'RHCache', :git => 'https://github.com/mszaro/RHCache'
end

I haven't submitted this to the Cocoapods master repo yet as I first intend to see if the original author will merge my fork back in. Until then, you will need to specify the git repo manually (as shown above).

License

All source code is licensed under the MIT License.