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Java

Posted by suryansh
suryansh
5,993 Points

Exceptional question for exceptional behaviour

I was just wondering, what would happen if we didn't catch an exception? Would it stop the program when encountered or would the compiler stop us from even compiling if we do not add a try-catch block or something else maybe?

Any answer is appreciated :D

3 Answers

markmneimneh
markmneimneh
14,133 Points

Hello

Please keep in mind that there are several type of exceptions ... or "errors"

Run time errors which occur during run time.

and

Compile time errors which are caught by the compilers at compile time ... before you even to get to run the program.

Now back to your question: "Would it stop the program when encountered or would the compiler stop us from even compiling if we do not add a try-catch block or something else maybe"

the answer is it depends on the type of the error.

if it is a compile time error/exception ... the compiler will stop you there ... at compile time. Example you forgot to the } closing in an if statement

if it is a run time error ... say you enter a zero from a command line and you divide a/0, and you did not catch this exception, an exception will be thrown and the program terminates immediatly.

If this answers your question, please mark the quation as answered.

Thank you

suryansh
suryansh
5,993 Points

Ah yes! I had forgotten about the types of errors and was thinking that exceptions and errors were 2 different things :P

Thank you very much! This was definitely the easiest answer to understand :)

Arthur Kharzamanov
Arthur Kharzamanov
5,414 Points
Arthur Kharzamanov
Arthur Kharzamanov
5,414 Points

In my understanding, when an exception occurs program processing gets terminated and doesn’t continue further. In such cases we get a system error message.

suryansh
suryansh
5,993 Points

Hmm... I was thinking the same thing

Seth Kroger
Seth Kroger
56,416 Points
Seth Kroger
Seth Kroger
56,416 Points

There are two categories of exceptions in Java, checked and unchecked.

Unchecked exceptions don't have to be caught or declared as thrown by the method. Unchecked exceptions are RuntimeException and any of its subclasses. Not handling them will not cause a compiler error.

Checked exceptions are any other subclass of Exception. These exceptions must be explicitly handled in a try/catch block or declared as thrown to let the next function up the chain handle them. Not doing so will cause an compiler error. IOException is an example of a checked exception.

Not catching an exception will terminate the program. This includes any checked exceptions you declare that main() throwns, since it's the last stop for checked expections.

suryansh
suryansh
5,993 Points

Thank you so much!