Using request Parameters in ADF Taskflow router

In order to use request parameters or parameters which are appended as query string in URL invoked ADF Taskflow, you will have to do two steps:

• Define a new parameter in "Input Parameter Definition" of taskflow and assign to it value of request parameter by
  
  #{pageFlowScope.requestParameterName}
  
  Actually ADF fetches request parameters and places in pageFlowScope when you call a Taskflow from URL
• Now use this newly defined parameter anywhere you want like in a condition of router by this
  
  #{pageFlowScope.parameterName == 'some conditional value'}

If you want to access this value in model layer e.g. after condition you want to execute a method, you can pass it as parameter or you can also access it programmatically by this:

ADFContext.getCurrent().getExpressionEvaluator().evaluate("#{pageFlowScope.yourParameterName}");