How can we access request parameters passed into an Action

You can obtain the request parameters by asking the ActionContext or implementing ParameterAware. Implementing ParameterAware is preferred.

Ask the ActionContext

The request parameters are available on the ActionContext instance, which is made available via ThreadLocal.

Map parameters = ActionContext.getContext().getParameters();

Implement ParameterAware

Preferred

Ensure that servlet-config Interceptor is included in the Action's stack.
- The default stack already includes servlet-config.
Edit the Action so that it implements the ParameterAware interface.
- The ParameterAware interface expects a setParameters method. You may wish to include a companion getParameters method.
At runtime, call getParameters to obtain a Map representing the request parameters.

Map parameters = this.getParameters();

When the servlet-config Interceptor sees that an Action implements ParameterAware, it passes a Map of the request parameters to the Action's setParameters method.

To unit test a ParameterAware Action, create your own Map with the pertinent request parameters and call setParameters as part of the test's setUp method.

@see struts-default.xml
@see org.apache.struts.action2.interceptor.ParameterAware
@see org.apache.struts.action2.interceptor.Servlet Config Interceptor