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JavaRanch » Java Forums » Certification » Programmer Certification (SCJP/OCPJP)
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Kedar Dravid
Ranch Hand

Joined: May 28, 2004
Posts: 333
Consider the following example from JQPlus:
public float parseFloat(String s)
float f = 0.0f;
f = Float.valueOf(s).floatValue();
return f ;
catch(NumberFormatException nfe)
System.out.println("Invalid input " + s);
f = Float.NaN ;
return f;
finally { System.out.println("finally"); }
return f ;

Which of the following statements about the above method are true?

a If input: "0.1" then it will return 0.1 and print finally.

b If input: "0x.1" then it will return Float.Nan and print Invalid Input 0x.1and finally.

c If input: "1" then it will return 1 and print finally.

d If input: "0x1" then it will return 0.0 and print Invalid Input 0x1 and finally.

e The code will not compile.

Answer: e
Explanation given:.
Note that the return statement after finally block is unreachable. Otherwise, choices 1, 2, 3 are valid.
I can't understand why/how the return statement is unreachable.
Also, assuming it is unreachable, shouldn't choice 3(c) print 1.0 and not 1?
Barry Gaunt
Ranch Hand

Joined: Aug 03, 2002
Posts: 7729
Where is it printing 1?

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Mike Gershman
Ranch Hand

Joined: Mar 13, 2004
Posts: 1272
If a NumberFormatException is not thrown, the finally clause will execute, then the first return statement, so the last return statement is not reached.

If a NumberFormatException is thrown, the catch clause is executed but the return action is delayed, then the finally clause is executed, then the delayed return action occurs. The final return statement is still not executed.
[ March 11, 2005: Message edited by: Mike Gershman ]

Mike Gershman
SCJP 1.4, SCWCD in process
Kedar Dravid
Ranch Hand

Joined: May 28, 2004
Posts: 333
Thanks, Mike!
I agree. Here's the link:
subject: return
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