• Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other Pie Elite all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Tim Cooke
  • Devaka Cooray
  • Ron McLeod
  • Jeanne Boyarsky
Sheriffs:
  • Liutauras Vilda
  • paul wheaton
  • Junilu Lacar
Saloon Keepers:
  • Tim Moores
  • Stephan van Hulst
  • Piet Souris
  • Carey Brown
  • Tim Holloway
Bartenders:
  • Martijn Verburg
  • Frits Walraven
  • Himai Minh

Character Constant...

 
Ranch Hand
Posts: 74
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
While clearing one mock exam, i found the following question, which is boggling me.



Now, can anybody give me the exact rule to indentify which is right and which is wrong option.

Thanks.
 
Ranch Hand
Posts: 40
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Did you try compiling it.
For me each one of them is right.

For character literals '\uxxxx' represents a Unicode character, where xxxx is a hexadecimal-format number in the range 0000 through FFFF.

'\xxx' - A character in octal representation; xxx must range from 000 through 377.
[ April 20, 2007: Message edited by: Tina Tibrewal ]
 
Pankaj Patel
Ranch Hand
Posts: 74
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
So according to you

should not give Compilation Problem but it does? So what is the Reason?
 
Ranch Hand
Posts: 294
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

from java lang spec:

Because Unicode escapes are processed very early, it is not correct to write '\u000a' for a character literal whose value is linefeed (LF); the Unicode escape \u000a is transformed into an actual linefeed in translation step 1 (�3.3) and the linefeed becomes a LineTerminator in step 2 (�3.4), and so the character literal is not valid in step 3. Instead, one should use the escape sequence '\n' (�3.10.6). Similarly, it is not correct to write '\u000d' for a character literal whose value is carriage return (CR). Instead, use '\r'.


[ April 20, 2007: Message edited by: raj malhotra ]
 
Pankaj Patel
Ranch Hand
Posts: 74
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Thanks Raj. So in order to be clear SCJP 5 with good score, i must read Java Language Specification.


Thanks you Very Much once again.
 
Ranch Hand
Posts: 100
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
can someone explain raj's answer a bit more clearly.

please
 
Ranch Hand
Posts: 42
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
It means that:

char c = '\u000a';

becomes

char c = ; // so this is a compile time error

before compilation.

Because Unicode escapes are processed very early



cheers,
 
straws are for suckers. tiny ads are for attractive people.
the value of filler advertising in 2021
https://coderanch.com/t/730886/filler-advertising
reply
    Bookmark Topic Watch Topic
  • New Topic