You might want to create parameters that are visible only locally to an ATG servlet bean. In that case, use the getLocalParameter(String paramName) and serviceLocalParameter(String paramName, ServletRequest, ServletResponse) methods. These methods return only values that are defined in the current frame for this invocation of the ATG servlet bean. This includes parameters passed to the ATG servlet bean between the open and close dsp:droplet tags and parameters defined at the top level of the called ATG servlet bean.

For example:

<dsp:param name="notLocalForA" value="x"/>

<dsp:droplet name="A">
    <dsp:param name="localForA" value="y"/>
</dsp:droplet>

In this example notLocalForA is not local for the ATG servlet bean A, and localForA is local.

Local parameters are useful because they allow the ATG servlet bean to determine which parameters are defined for a particular ATG servlet bean call. Without local parameters, it can be easy to get into an infinite loop by nesting different ATG servlet beans, as the inner ATG servlet bean always sees all parameters defined to the outer one.