Consultor Eletrônico

Status: Verified

SYMPTOM(s):

4GL/ABL: Errors (9082) and (9102) referencing an X-noderef Object Handle attribute or invoking one of its methods.

X-NODEREF or X-DOCUMENT <method-name> got an error: <xml-exception>. (9082)

X-NODEREF or X-DOCUMENT GET-CHILD got an error: Invalid child index. (9082)

X-NODEREF must be associated with a valid X-DOCUMENT in order to use it in method <method>. (9102)

X-NODEREF must be associated with a valid X-DOCUMENT in order to use it in method NODE-VALUE. (9102)

X-NODEREF must be associated with a valid X-DOCUMENT in order to use it in method LOCAL-NAME. (9102)

The errors are generated on running a 4GL procedure that includes code like:
...
ASSIGN
hParentNode:GET-CHILD(hChildNode,1).

DISPLAY
hChildNode:LOCAL-NAME FORMAT "X(35)" LABEL "ChildName"
hChildNode:NODE-VALUE LABEL "SubValue".
...

FACT(s) (Environment):

All Supported Operating Systems
Progress 9.1x
OpenEdge 10.x

CAUSE:

The hParentNode is childless causing hParentNode:GET-CHILD(hChildNode,1) to return an invalid hChildNode handle. Since the hChildNode is not a valid handle, all attempts to access any of its attributes or invoke any of its methods fail.

FIX:

Ensure that node reference object handle is valid before calling its methods or accessing its attributes. For example, to correct the code snippet above, ASSIGN the result of the GET-CHILD() method to a logical variable using the NO-ERROR option and check if it is TRUE before referencing any of the hChildNode attributes or methods:

...
DEFINE VARIABLE lReturnValue AS LOGICAL NO-UNDO.
ASSIGN
lReturnValue = hParentNode:GET-CHILD(hChildNode,1) NO-ERROR.

IF lReturnValue = TRUE THEN
DISPLAY
hChildNode:LOCAL-NAME FORMAT "X(35)" LABEL "ChildName"
hChildNode:NODE-VALUE LABEL "SubValue".
ELSE
MESSAGE
"Current Node is childless. "
VIEW-AS ALERT-BOX INFO BUTTONS OK.
...