MACROMEDIA COLDFUSION MX 61-DEVELOPING COLDFUSION MX, Develop Manual

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Creating and using CORBA objects 779
The following sections describe how to call CORBA methods correctly in ColdFusion.
Method name case considerations
Method names in IDL are case-sensitive. However, ColdFusion is case-insensitive. Therefore, do
no use methods that differ only in case in IDL.
For example, the following IDL method declarations correspond to two different methods:
testCall(in string a); // method #1
TestCall(in string a); // method #2
However, ColdFusion cannot differentiate between the two methods. If you call either method,
you cannot be sure which of the two will be invoked.
Passing parameters by value (in parameters)
CORBA in parameters are always passed by value. When calling a CORBA method with a
variable in ColdFusion, specify the variable name without quotes, as shown in the following
example:
Passing variables by reference (out and inout parameters)
CORBA out and inout parameters are always passed by reference. As a result, if the CORBA
object modifies the value of the variable that you pass when you invoke the method, your
ColdFusion page gets the modified value.
To pass a parameter by reference in ColdFusion, specify the variable name in double quotes in the
CORBA method. The following example shows an IDL line that defines a method with a string
variable, b, that is passed in and out of the method by reference. It also shows CFML that calls
this method.
In this case, the ColdFusion variable foo corresponds to the inout parameter b. When the CFML
executes, the following happens:
1
ColdFusion calls the method, passing it the variable by reference.
2
The CORBA method replaces the value passed in, "My Initial String", with some other value.
Because the variable was passed by reference, this modifies the value of the ColdFusion variable.
3
The
cfoutput
tag prints the new value of the foo variable.
IDL
void method(in string a);
CFML
<cfset foo="my string">
<cfset ret=handle.method(foo)>
IDL
void method(in string a, inout string b);
CFML
<cfset foo = "My Initial String">
<cfset ret=handle.method(bar, "foo")>
<cfoutput>#foo#</cfoutput>