File APIs for Java Developers
Manipulate DOC, XLS, PPT, PDF and many others from your application.
The moose likes Programmer Certification (SCJP/OCPJP) and the fly likes char primitive default value Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login
JavaRanch » Java Forums » Certification » Programmer Certification (SCJP/OCPJP)
Bookmark "char primitive default value" Watch "char primitive default value" New topic

char primitive default value

anand phulwani
Ranch Hand

Joined: Sep 10, 2005
Posts: 242
Here I have two problems,
1)When the JVM is implicitly initialising the default value of the char primitive a,b,c ,after that its printing its Unicode value as -1, why so ?,
Shouldn't It print 0.

2)my second problem is when i initialize c=' '; the Unicode Value of b and c both is -1 ,when printed ,but when a test for equality is cheked between b and c its returning false.

Results into the output

a's Unicode Value= -1
b's Unicode Value= -1
c's Unicode Value= -1
Sorry!,b is not equal to c

With Regds,

Thanks and Regards, Anand
SCJP 5.0 310-055 73%, SCWCD 1.4 310-081 78%, IBM DB2 9 Fundamentals 000-730 62%
Sandeep Chhabra
Ranch Hand

Joined: Aug 28, 2005
Posts: 340
Anand This might help you

public static int getNumericValue(char ch)Returns the int value that the specified Unicode character represents. For example, the character '\u216C' (the roman numeral fifty) will return an int with a value of 50.
The letters A-Z in their uppercase ('\u0041' through '\u005A'), lowercase ('\u0061' through '\u007A'), and full width variant ('\uFF21' through '\uFF3A' and '\uFF41' through '\uFF5A') forms have numeric values from 10 through 35. This is independent of the Unicode specification, which does not assign numeric values to these char values.

If the character does not have a numeric value, then -1 is returned. If the character has a numeric value that cannot be represented as a nonnegative integer (for example, a fractional value), then -2 is returned.

Note: This method cannot handle supplementary characters. To support all Unicode characters, including supplementary characters, use the getNumericValue(int) method.

ch - the character to be converted.
the numeric value of the character, as a nonnegative int value; -2 if the character has a numeric value that is not a nonnegative integer; -1 if the character has no numeric value.


Regards<br />Sandy<br />[SCJP 5.0 - 75%]<br />[SCWCD 1.4 - 85%]<br />------------------<br />Tiger, Tiger burning bright,<br />Like a geek who works all night,<br />What new-fangled bit or byte,<br />Could ease the hacker's weary plight?
Sandeep Chhabra
Ranch Hand

Joined: Aug 28, 2005
Posts: 340
And for your second question

B wil never be equal to C; since you have assigned a space to c
c=' ';
having the unicode value of 32;
whereas b contains its default value ie. '\u0000' or the unicode value 0

hence 32==0 will return false.

Hope this helps

[ September 19, 2005: Message edited by: Sandeep Chhabra ]
Vlado Zajac
Ranch Hand

Joined: Aug 03, 2004
Posts: 245
To print unicode value of some character (like 65 for 'A' or 32 for space), convert it to int.

I agree. Here's the link:
subject: char primitive default value
It's not a secret anymore!