26 lines
956 B
Objective-C
26 lines
956 B
Objective-C
#import <Foundation/Foundation.h>
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/**
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*
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* A bloom filter allows a set of items to be represented compactly, at the cost of false-positives when checking membership.
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* When contains returns true, the given item may be in the set.
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* When contains returns false, the given item is definitely not in the set.
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*
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* Bloom filters are used to opportunistically avoid starting an expensive operation that always fails for items not in a set.
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* In the specific case of RedPhone, it is used to determine if a phone number can be called (i.e. is in the RedPhone directory).
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*
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*/
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@interface BloomFilter : NSObject
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@property (nonatomic,readonly) NSUInteger hashCount;
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@property (nonatomic,readonly) NSData* data;
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+(BloomFilter*) bloomFilterWithHashCount:(NSUInteger)hashCount
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andData:(NSData*)data;
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+(BloomFilter*) bloomFilterWithNothing;
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+(BloomFilter*) bloomFilterWithEverything;
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-(bool) contains:(NSString*)entity;
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@end
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