21.4

java.util.Dictionary

THE PACKAGE JAVA.UTIL

21.4.4

abstract public Object put(Object key, Object element)

throws NullPointerException

The general contract for the

put

 method is that it adds an entry to this dictionary.

If this dictionary already contains an entry for the specified

key

, the element

already in this dictionary for that

key

 is returned, after modifying the entry to con 

tain the new

element

.

If this dictionary does not already have an entry for the specified

key

, an entry

is created for the specified

key

 and

element

, and

null

 is returned.

If the

key

 or the

element

 is

null

, a

NullPointerException

 is thrown.

21.4.5

abstract public Object remove(Object key)

throws NullPointerException

The general contract for the

remove

 method is that it removes an entry from this

dictionary.

If this dictionary contains an entry for the specified

key

, the element in this

dictionary for that

key

 is returned, after removing the entry from this dictionary.

If this dictionary does not already have an entry for the specified

key

,

null

 is

returned.

If the

key

 is

null

, a

NullPointerException

 is thrown.

21.4.6

abstract public Enumeration keys()

The general contract for the

keys

 method is that an

Enumeration

 ( 21.1) is

returned that will generate all the keys for which this dictionary contains entries.

21.4.7

abstract public Enumeration elements()

The general contract for the

elements

 method is that an

Enumeration

 ( 21.1) is

returned that will generate all the elements contained in entries in this dictionary.

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