try, catch and finally

[Tony Xu]

I'm a little confused by some answers from mock exams. Want help.
My understanding is that the following are valid.
(1)try {//block}; catch(Exception e){//block};
(2)try {//block}; catch(Exception e){//block}; finally {//block};
(3)try {//block}; finally{//block};
(4)in all 1 to 3, can replace catch block with a series catches in the a specific order (more general) is fine;
(5)no try block then no catch block;
(6)no try block then no finally block.
Am I right? Please clarify and add.

[Jennifer Warren]

All the statements seems to be alright just you should not be putting semi-column after the blocks of code.
thanx.
Jennifer.

[Ragu Sivaraman]

1.try/catch ...finally not mandatory
2.Specific catch first, more general exceptions later
3. return must be the last statement in a try catch finally mechanism. Statements become unreachable(compile time err) if there is any statements declared after return statement
4. if try/catch/finally all the three has return... finally return will override all the above ones
Correct me if i am wrong

[Jose Botella]

Ragu is rigth regarding point 4)
Another point:
try{ /*break or continue or return or throw*/ }
finally{ /*break or continue or return or throw*/ }
This case means the instruction that was going to leave out the try clause is not executed. It would be executed only if finally returns. Note that is possible to lost an important exception thrown in try.
Another similar:
try { /*break or continue or return or throw*/ }
catch{ /*break or continue or return or throw*/ }
finally{ /*break or continue or return or throw*/ }

[Thomas Paul]

Originally posted by Ragu Sivaraman:
3. return must be the last statement in a try catch finally mechanism.

If a return makes statements unreachable, it must be the last statement within a catch block. The return is not required.

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Tom - SCJP --- Co-Moderator of the Programmer Certification Forums