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Joined: Jan 15, 2002
Posts: 5
why isnt null a reserved word in java?
Michael Ernest
High Plains Drifter

Joined: Oct 25, 2000
Posts: 7292

It is.
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- Robert Bresson

Joined: Jan 15, 2002
Posts: 5
but it is not listed in Brodgen's Cram book.
I was too hurry to ask the question, sorry.
I could not modify the name in myprofile.
Cindy Glass
"The Hood"

Joined: Sep 29, 2000
Posts: 8521
"null" is not a Keyword, but it is a reserved literal.
From the Java Language Specification

3.9 Keywords
The following character sequences, formed from ASCII letters, are reserved for use as keywords and cannot be used as identifiers (�3.8):
Keyword: one of
abstract default if private this
boolean do implements protected throw
break double import public throws
byte else instanceof return transient
case extends int short try
catch final interface static void
char finally long strictfp volatile
class float native super while
const for new switch
continue goto package synchronized
The keywords const and goto are reserved, even though they are not currently used. This may allow a Java compiler to produce better error messages if these C++ keywords incorrectly appear in programs.
While true and false might appear to be keywords, they are technically Boolean literals (�3.10.3). Similarly, while null might appear to be a keyword, it is technically the null literal (�3.10.7).


3.10.7 The Null Literal
The null type has one value, the null reference, represented by the literal null, which is formed from ASCII characters. A null literal is always of the null type.

[ January 15, 2002: Message edited by: Cindy Glass ]

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Joined: Jan 15, 2002
Posts: 5
I agree. Here's the link:
subject: null
It's not a secret anymore!