package username.dict;

import java.io.PrintWriter;

/**
 * Dictionaries that can have specified index and value types.
 *
 * @author Samuel A. Rebelsky
 * @version 1.1 of April 2006
 */
public interface Dict<K,V>
{
  /**
   * Add something to the dictionary (or replace something already
   * in the dictionary).
   * 
   * @pre
   *   key is not null.
   * @pre
   *   value is not null.
   * @post
   *   this.get(key) returns value.
   */
  public void put(K key, V value);

  /**
   * Get something from the dictionary.
   *
   * @pre
   *   key is not null.
   * @post
   *   Returns the most recent value for this.put(index,value).
   * @exception NoSuchKeyException
   *   If the key does not appear in the dictionary.
   */
  public V get(K key)
    throws NoSuchKeyException;

  /**
   * Dump the dictionary to the screen or to a file.
   */
  void dump(PrintWriter pen);
 
} // interface Dict<K,V>