Are true and false keywords?

Question

Are true and false keywords in Java?

This question was in fact answered in your previous question on this topic: http://stackoverflow.com/questions/519631/java-keywords — Greg Hewgill, Feb 23 '09 at 01:52

score 27 · Answer 1 · answered Feb 23 '09 at 01:15

27

Here's the complete list of Java Language Keywords. In particular, note that

true, false, and null might seem like keywords, but they are actually literals; you cannot use them as identifiers in your programs.

answered Feb 23 '09 at 01:15

Zach Scrivena

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Can you explain the difference? – Tim Matthews Feb 23 '09 at 01:23
It's syntactical. Literals represent values, like "Hello" and 42, whereas keywords don't. – Zach Scrivena Feb 23 '09 at 01:26
OK but why isn't true,false,null a keyword as well as a literal? – Tim Matthews Feb 23 '09 at 01:36
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"Keywords" and "literals" are mutually exclusive, by their definition. – Zach Scrivena Feb 23 '09 at 01:39
i the java language specification, it says "The tokens are the identifiers (§3.8), keywords (§3.9), literals (§3.10), separators (§3.11), and operators (§3.12) of the syntactic grammar.". so by saying "false, ..." is not a keyword, that maybe simplifies matters. i dunno – Johannes Schaub - litb Feb 23 '09 at 01:55
Thanks Zach. Now bookmark the link, it will refrain you from posting lot of other questions. – Adeel Ansari Feb 23 '09 at 02:03
@CAD1337: what would be gained if they where keywords? – Joachim Sauer Apr 15 '09 at 11:36

score 22 · Accepted Answer · edited Apr 15 '09 at 11:35

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No. true and false are literals.

edited Apr 15 '09 at 11:35

Joachim Sauer

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answered Feb 23 '09 at 01:12

Warrior

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score 1 · Answer 3 · answered Jan 04 '13 at 10:25

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No. true and false are literals in java. Literals are something which are actual values not the variable names. Though they are not part of keywords list of java they are considered to be the reserved ones. If you try to use them as variables you will get compile error saying - invalid VariableDeclaratorId

answered Jan 04 '13 at 10:25

Rishikesh Dhokare

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sir you are awesome :) – STEEL Feb 09 '18 at 06:20

score 1 · Answer 4 · answered Feb 23 '09 at 01:13

1

No, but they're reserved.

answered Feb 23 '09 at 01:13

Giovanni Galbo

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score 1 · Answer 5 · answered Mar 12 '12 at 11:20

No true, false are not keywords they are actually literals; you cannot use them as identifiers in your programs. Here is the complete list of keywords in java

abstract        continue            for           new           switch
assert***       default         goto*             package   synchronized
boolean     do                  if            private   this
break       double          implements    protected throw
byte        else            import            public    throws
case        enum****            instanceof    return    transient
catch       extends         int           short         try
char        final           interface     static    void
class       finally         long              strictfp**    volatile
const*      float           native            super         while

*   not used
**  added in 1.2
*** added in 1.4
****    added in 5.0

Are true and false keywords?

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