The Program Flow for a Location
Use
This is only available in a location. Tracing the flow of a program is a common practice: entering, exiting, throwing, assertion.
● entering() – outputs a default message (“Entering Method” with Path severity) indicating that it is entering a source block.
Always paired up with the exiting() method.
The entering() Method
Method |
Description |
entering() |
Entering a source block in general. |
entering(String subloc) |
Specifies the method name in subloc. |
entering(Object[] args) |
A general source block with arguments: “Entering method with <args>”. |
entering(String subloc, Object[] args) |
The same as the previous one, but with a specific method name. |
● exiting() – outputs a default message (“Exiting Method” with Path severity), indicating that it is leaving a source block.
Always paired up with the entering() method.
The exiting() Method
Method |
Description |
exiting() |
Exiting a source block in general. As long as the method name (subloc) is specified in ‘entering’, it is no longer necessary to provide a subloc as argument. The result are presented in the sample code snippet below. |
exiting(String subloc) //DEPRECATED |
Specifies the method name in subloc |
exiting(Object res) |
A general source block with result: “Exiting method with <res>”. |
exiting(String subloc, Object res) |
The same as the previous one, but with a specific method name. |
To reiterate, refer to the sample code with method announce(Object o):
Always log the entering and exiting methods together.
public void announce(Object o) { String method = "announce(java.lang.Object)"; loc.entering(method); try { } catch (Exception e) { } loc.exiting(); } |
The potential output, assuming the simplest case with ConsoleLog and default TraceFormatter, is:
|
May 3, 2001 6:54:18 PM com.sap.fooPackage.Node.announce [main] Path: Exiting method |
● throwing() – a warning message (“Throwing …”) indicating that the source block is about to throw an exception.
The throwing() Method
Method |
Description |
throwing(Throwable exc) |
Throws the exception exc. |
Throwing(String subloc, Throwable exc) |
The same as the previous one, but with a specific method name. |
● assertion() – to test a condition and output an error message, normally with the assertion included (“Assertion failed: <assertion test>”) when the evaluation is false.
The assertion() Method
Method |
Description |
assertion(Boolean assertion, String desc) |
Evaluates the assertion. If false, prints desc with the default message: “Assertion failed: <desc>”, where <desc> is the assertion test itself, for example 5 > 3. |
assertion(String subloc, Boolean assertion, String desc) |
The same as the previous one, but with a specific method name. |
To reiterate, refer to the sample code with method announce(Object o):
public void announce(Object o) { String method = "announce(java.lang.Object)"; loc.assertion(method, 5 < 3,"Stupid comparison“); try { } catch (Exception e) { loc.throwing(method, e); } } |
The potential output, assuming the simplest case with ConsoleLog and default TraceFormatter, is:
|
Error: Assertion failed: Stupid comparison May 3, 2001 6:54:18 PM com.sap.fooPackage.Node.announce [main] Warning: Throwing java.io.FileNotFoundException: C:\Not_Exist\zzzzz.log (The system cannot find the path specified) |
See also: