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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 any class, such as Hashtable, which maps keys to values. Any non-null object can be used as a key and as a value.

As a rule, the equals method should be used by implementations of this class to decide if two keys are the same.

See Also:
equals, hashCode, Hashtable

Constructor Index

o Dictionary()

Method Index

o elements()
Returns an enumeration of the values in this dictionary.
o get(Object)
Returns the value to which the key is mapped in this dictionary.
o isEmpty()
Tests if this dictionary maps no keys to value.
o keys()
Returns an enumeration of the keys in this dictionary.
o put(Object, Object)
Maps the specified key to the specified value in this dictionary.
o remove(Object)
Removes the key (and its corresponding value) from this dictionary.
o size()
Returns the number of keys in this dictionary.

Constructors

o Dictionary 
    method Dictionary() public

Methods

o size 
    method size() returns int public abstract
Returns the number of keys in this dictionary.

Returns:
the number of keys in this dictionary.
o isEmpty 
    method isEmpty() returns boolean public abstract
Tests if this dictionary maps no keys to value.

Returns:
true if this dictionary maps no keys to values; false otherwise.
o keys 
    method keys() returns Enumeration public abstract
Returns an enumeration of the keys in this dictionary.

Returns:
an enumeration of the keys in this dictionary.
See Also:
elements, Enumeration
o elements 
    method elements() returns Enumeration public abstract
Returns an enumeration of the values in this dictionary. the Enumeration methods on the returned object to fetch the elements sequentially.

Returns:
an enumeration of the values in this dictionary.
See Also:
keys, Enumeration
o get 
    method get(key=Object) returns Object public abstract
Returns the value to which the key is mapped in this dictionary.

Parameters:
key - a key in this dictionary. null if the key is not mapped to any value in this dictionary.
Returns:
the value to which the key is mapped in this dictionary;
See Also:
put
o put 
    method put(key=Object, -
               value=Object) returns Object public abstract
Maps the specified key to the specified value in this dictionary. Neither the key nor the value can be null.

The value can be retrieved by calling the get method with a key that is equal to the original key.

Parameters:
key - the hashtable key.
value - the value.
Returns:
the previous value to which the key was mapped in this dictionary, or null if the key did not have a previous mapping.
Throws: NullPointerException
if the key or value is null.
See Also:
equals, get
o remove 
    method remove(key=Object) returns Object public abstract
Removes the key (and its corresponding value) from this dictionary. This method does nothing if the key is not in this dictionary.

Parameters:
key - the key that needs to be removed.
Returns:
the value to which the key had been mapped in this dictionary, or null if the key did not have a mapping. 
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