Object function_name (Java datatype x1[, 
                                      Java datatype x2 ...] ) 
                                      throws SDK Exception
{
return (Object)invokeJExpression( String expression, 
                                  new Object [] { x1[, x2, ... ]}  );
}

JExpression function_name ()  throws SDKException
{
    JExprParamMetadata params[] = new JExprParamMetadata[number of parameters];
    params[0] = new JExprParamMetadata (
                    EDataType.STRING,  // data type
                    20,  // precision
                    0    // scale
                    );
...
    params[number of parameters - 1] = new JExprParamMetadata (
                    EDataType.STRING,  // data type
                    20,  // precision
                    0    // scale
                    );
...
    return defineJExpression(String expression,params);
}