The document discusses Java Hashtables. It notes that Hashtables relate keys to values, can use any non-null object as a key or value, and require hashcode and equals methods for key objects. Hashtables have initial capacity and load factor parameters and store key-value pairs of any object type. The document also provides an example hash function that returns a position in the table using Horner's rule by iterating through the first 3 characters of a string key.

1. Hashtable
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2. Java Hashtable
 Relates a key with a value.
 Any non-null object can be used as a key or as
a value.
 Should be implemented hashcode and equals
methods for the objects used as keys.
 Objects in the hash table have two parameters
initial capacity and load factor.

3. Using Object Types
 Store pairs of type, object type key value.

4. Hash function
 Returns a value that represents the position in
the table
 Using Horner's rule.
private int hash(String key){
int p=0;
for(int i=0;i<key.length() && i<3;i++){
p=(p*32+key.charAt(i))%table.length;
}
return p;
}