package structure; import java.util.Iterator; /** * Associations establish a link between a key and a value. * An associative array or map is a structure that allows a disjoint * set of keys to become associated with an arbitrary set of values. * The convenience of an associative array is that the values used to * index the elements need not be comparable and their range need not * be known ahead of time. Furthermore, there is no upper bound on * the size of the structure. It is able to maintain an arbitrary number * of different pieces of information simultaneously. Maps are sometimes * called dictionaries because of the uniqueness of the association of * words and definitions in a household dictionary. *
* This class implements methods common to all maps and should be
* extended by classes that wish to implement the map interface.
*/
public abstract class AbstractMap