cpsc331.collections

Class SimpleChainHashFunction<E>

java.lang.Object

cpsc331.collections.SimpleChainHashFunction<E>

All Implemented Interfaces:

ChainHashFunction<E>

public class SimpleChainHashFunction<E>
extends java.lang.Object
implements ChainHashFunction<E>

Provides an implementation of a ChainHashFunction — that is, a class providing a hash function for a hash table with chaining — by making a straightforward use of Java’s hashCode function

Constructor Summary

Constructors

Constructor and Description
SimpleChainHashFunction(int T) Provides a hash function for a hash table with chaining, for a given table size

Method Summary

Modifier and Type	Method and Description
int	hashValue(E e) Reports the hash value for a given value

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SimpleChainHashFunction

public SimpleChainHashFunction(int T)
                        throws java.lang.IllegalArgumentException

Provides a hash function for a hash table with chaining, for a given table size

Parameters:

T - table size

Throws:

java.lang.IllegalArgumentException - if the input table size is not positive

Precondition: An integer T is given as input.
Postcondition: If T is positive then a ChainHasFunction that can be used with a hash table of size T is created. An IllegalArgumentException is thrown otherwise.

Method Detail

hashValue

public int hashValue(E e)

Description copied from interface: ChainHashFunction

Reports the hash value for a given value

Specified by:

hashValue in interface ChainHashFunction<E>

Parameters:

e - the element whose has value is to be provided

Returns:

the hash value for this element

Precondition:

1. An element e of type E has been given as input.

Postcondition:

1. The has value of e — an integer between zero and one less than the size of the supported has table — is returned as output.