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# Class java.util.Dictionary

    java.lang.Object
       |
       +----java.util.Dictionary

public class Dictionary
extends Object

The Dictionary class is the abstract parent of Hashtable, which maps keys to values. Any object can be used as a key and/or value.

See Also:
  Hashtable, hashCode, equals

##

Dictionary()

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elements()
  Returns an enumeration of the elements.
get(Object)
  Gets the object associated with the specified key in the Dictionary.
isEmpty()
  Returns true if the Dictionary contains no elements.
keys()
  Returns an enumeration of the Dictionary's keys.
put(Object, Object)
  Puts the specified element into the Dictionary, using the specified key.
remove(Object)
  Removes the element corresponding to the key.
size()
  Returns the number of elements contained within the Dictionary.

##

Dictionary

      public Dictionary()

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size

      public abstract int size()

  Returns the number of elements contained within the Dictionary.

isEmpty

      public abstract boolean isEmpty()

  Returns true if the Dictionary contains no elements.

keys

      public abstract Enumeration keys()

  Returns an enumeration of the Dictionary's keys.

  See Also:
    elements, Enumeration

elements

      public abstract Enumeration elements()

  Returns an enumeration of the elements. Use the Enumeration methods on the returned object to fetch the elements sequentially.

  See Also:
    keys, Enumeration

get

      public abstract Object get(Object key)

  Gets the object associated with the specified key in the Dictionary.

  Parameters:
    key - the key in the hash table
  Returns:
    s the element for the key, or null if the key is not defined in the hash table.
  See Also:
    put

put

      public abstract Object put(Object key,
                                 Object value)

  Puts the specified element into the Dictionary, using the specified key. The element may be retrieved by doing a get() with the same key. The key and the element cannot be null.

  Parameters:
    key - the specified hashtable key
    value - the specified element
  Returns:
    the old value of the key, or null if it did not have one.
  Throws: NullPointerException
    If the value of the specified element is null.
  See Also:
    get

remove

      public abstract Object remove(Object key)

  Removes the element corresponding to the key. Does nothing if the key is not present.

  Parameters:
    key - the key that needs to be removed
  Returns:
    the value of key, or null if the key was not found.

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