A metadata parameter's "set" method should accept a single argument, whose data type will define the data type of the parameter. For connections, this type should be limited to a Java primitive or a java.lang. String. Arrays (or sequence parameters) are allowed, but the adapter's administrative interface only provides widgets to access the first element of the array. Other object types are interpreted as external Java bean classes, as described in Implementing Metadata Parameters Using External Classes.

In addition to defining the parameter name and data type, the "set" method of a metadata parameter is used at run time to pass the value of the parameter to the connection factory. The examples shown in this section show metadata accessor methods as methods of the connection factory implementation class. In fact, any method in the connection factory implementation conforming to the naming convention will be interpreted as a metadata parameter accessor method.