integer a = 123;
integer b = 0;
integer c;
try {
c = a / b; // throws ArithmeticException
printLog(info, c); // skipped
} catch (CTLException ex) {
c = -1; // workaround: set the variable to -1 to indicate error
printLog(warn, ex); // log a warning
}
Try-Catch Statement
Since CloverDX 5.6, you may use the try-catch
statement to handle runtime errors.
The execution starts by first executing the try
block.
Then there is a choice:
-
If the
try
block completes normally,then no further action is taken, thecatch
block is skippedand the wholetry-catch
statement completes normally. -
If the code inside the
try
block throws an exception,the execution jumps to the beginning of the respectivecatch
block.It is up to you how you handle the exception there.For example, you can execute some alternative code to work around the problem that caused the exception.Or you can throw a custom error using theraiseError()
function. Or you can just log the exception and have the execution complete normally.Some details about the exception can be accessed via theCTLException
data structure.
For every try
block, there can be only one catch
block, because there is just one type of exception: CTLException
.
Also, there is no finally
block in CTL.
try-catch
statements can be nested.
CTLException
is actually a data record with the following fields:
sourceRow: integer
-
the row of the CTL source code where the exception occurred
sourceColumn: integer
-
the column of the CTL source code where the exception occurred
message: string
-
the error message of the innermost exception - the original cause of the failure
cause: string
-
the type of the innermost exception, e.g.
java.lang.ArithmeticException
stackTrace: list[string]
-
the cascade of function calls that caused the failure
exceptionTrace: list[string]
-
the list of exception types from the outermost to the innermost