The syntax of a try block (which is a statement in C++) is try compound-statement handler-sequence And the syntax of if is: attr(optional) if ( condition ) statement_true attr(optional) if ( condition ) statement_true else statement_false where: statement-true – any statement (often a compound statement), which is executed if condition evaluates to true statement-false – … Read more
Problem: Logging the error object to console by itself will reveal that the object is indeed not empty and grabbing properties such as err.message is very doable. The problem is that JS Error object cannot be naively stringified using JSON. This – along with ways to deal with this problem – are described in detail … Read more
you can use raiserror. Read more details here –from MSDN BEGIN TRY — RAISERROR with severity 11-19 will cause execution to — jump to the CATCH block. RAISERROR (‘Error raised in TRY block.’, — Message text. 16, — Severity. 1 — State. ); END TRY BEGIN CATCH DECLARE @ErrorMessage NVARCHAR(4000); DECLARE @ErrorSeverity INT; DECLARE @ErrorState … Read more
Normally, I’d argue that you should either log or rethrow. Doing both will just cause every layer to log the exception again and again, which makes the logs hard to read. Even worse, it’s hard to figure out how many errors you actually have – was it seven errors, or seven layers of the app … Read more
TL;DR NO, exceptions are usually faster on the non-exceptional path compared to error code handling. Well, the obvious remark is compared to what ? Compared to not handling the error, it obviously decrease performance; but is performance worth the lack of correctness ? I would argue it is not, so let us supposed that you … Read more
This is the correct idom (and it works fine): InputStream in = null; OutputStream out = null; try { in = new FileInputStream(inputFileName); out = new FileOutputStream(outputFileName); copy(in, out); finally { close(in); close(out); } public static void close(Closeable c) { if (c == null) return; try { c.close(); } catch (IOException e) { //log the … Read more
The most useful case is when you need to release some resources : InputStream is = … try { //code… } catch (Exception e) { //code… } finally { is.close(); } More generally, you use it when you want to be sure your code is executed at the end, even if there was an exception … Read more
Note that the following is only applicable for Java 6 and earlier. For Java 7 and later, you should switch to using try-with-resources … as described in other answers. If you are trying to catch and report all exceptions at source (in Java 6 or earlier), a better solution is this: ObjectOutputStream oos = null; … Read more
Poor implementations of exception handlers push some kind of exception handler block for each try clause on the runtime stack as the try clause is entered, and pop it off as the try clause is exited. A location holding the address of the most recently pushed exception handler block is also maintained. Typically these exception … Read more
Unfortunately, compilers can’t work on theoretical principles, and even though you may know that it is safe in your case, if they allowed it, it would have to be safe for all cases. In other words, the compiler isn’t stopping just you, it’s stopping everyone, including all those that don’t know that it is unsafe … Read more