Interface Methods for a RAD Module
Each method in an interface is defined by a method
element. The name of a method is defined by this element's mandatory name
attribute. The other properties of a method are defined by child elements of the method
.
If a method has a return value, it is defined using a single result
element. The type of the return value is specified in the same way the type is specified for a structure field. If no result
element is present, the method has no return value.
If a method can fail for an API-specific reason, it is defined using a single error
element. The type of an error is specified the same way the type is specified for a structure field. Unlike a structure field, an error need not specify a type. Such a situation is indicated by an error
element with no attributes or child elements. If no error
element is present, the method will only fail if there is a connectivity problem between the client and the server.
A method's arguments are defined, in order, with zero or more argument
elements. Each argument
element has a mandatory name
attribute. The type of an argument is specified in the same way the type is specified for a structure field.
Example 2-5 Defining a Method for a RAD Module
<struct name="Meal">...</struct> <struct name="Ingredient">...</struct> <method name="cook"> <result type="Meal" /> <error /> <argument type="string" name="name" nullable="true" /> <argument name="ingredients"> <list type="Ingredient" /> </argument> </method>