/***************************************************************************

* File: UniversalHashFunction.java

* Author: Keith Schwarz (htiek@cs.stanford.edu)

*

* An object representing a family of universal hash functions. The object

* can then hand back random instances of the universal hash function on an

* as-needed basis.

*/

public interface UniversalHashFunction<T> {

/**

* Given as input the number of buckets, produces a random hash function

* that hashes objects of type T into those buckets with the guarantee

* that

*<pre>

* Pr[h(x) == h(y)] <= |T| / numBuckets, forall x != y

*</pre>

* For all hash functions handed back.

*

* @param buckets The number of buckets into which elements should be

* partitioned.

* @return A random hash function whose distribution satisfies the above

* property.

*/

public HashFunction<T> randomHashFunction(int buckets);

}