Originally posted by kathir vel: ... Should I know all unicodes for all characters for SCJP exam?...
No. I think this question is just illustrating that a char literal can be expressed as a Unicode value and a char is int convertible (so it can be used in a switch/case). You should know the correct format for a Unicode char literal (for example, '\u0042'), but you do not need to know how the values translate.
"We're kind of on the level of crossword puzzle writers... And no one ever goes to them and gives them an award." ~Joe Strummer sscce.org
I don't think this is actually on the exam, but here's a detail to keep in mind. Unicode carriage returns ('\u000d') and line feeds ('\u000a') are not valid Java literals. The reason is that Unicode values are translated very early by the compiler, so instead of a char literal, it's as if you had an actual carriage return or line feed in your code.