Throughout StreamBase in EventFlow programs, there is a single concept of a parameter,
and a single ${param} syntax to resolve parameters to
their values. Parameters can be declared at various points in an application or
configuration file, each having a different scope, and order of precedence. In general,
there are two categories of parameters:
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Module Parameters: Module parameters are declared at the module level, and their scope is the containing module. In EventFlow programs, declare module parameters in the Parameters tab of the EventFlow Editor. You can reference module parameters in expressions in any operator or adapter in the containing module. You can set values for module parameters in a number of ways. Module parameters are evaluated at module load time, when the container holding the module is started by its hosting StreamBase Server.
If a module parameter is declared with a default value, and you do not specify a value at runtime with any of the available methods, then the module is run using the default value for that parameter. If you do not declare a default value, the containing module does not pass typechecking. See the Using Module Parameters documentation page for more information.
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Container Parameters: Container parameters are referenced with the same syntax as module parameters. If a container parameter of the same name is declared in the parent Container element reference the module parameter value supersedes the value of the container parameter. They are evaluated at module load time, when the container holding the module is started by its hosting StreamBase Server.