/*
 * Created on Jul 27, 2004
 */
package hashing;

/** An object which can hash other objects. 
 * <br />
 * Concrete classes should have a constructor which takes a single argument
 * as follows:
 * <br />
 * module - an integer -1.  Set the modulus to be used for the final stage of computing the hash
	 * value.  All hash values produced will be in the range 0..modulus-1.
 * @author dickey
 */
public interface IHasher {
		
	/** Produce a hash value for the given object.  
	 * 
	 * @param obj any non-null object.
	 * @return a value in the range 0..modulus-1, where modulus is the modulus 
	 * supplied when the hasher was created.
	 */
	int hash(Object obj);
	
	/** Report what modulus this hash function is using.
	 * 
	 * @return the modulus used by this hasher to limit the range of hash
	 * values produced.
	 */
	int getModulus();

}