Custom State Variables

You can define input and output variables for custom states. Variables are used as both metadata in the state editor, and as runtime objects for storing session variables.

// Define input variable
   
private static final TextBoxAttribute inPostCode = 
        new TextBoxAttribute("POSTCODE", "Zip or Postal Code", false);        
   
// Define output variable    
   
private static final OutputAttribute outWeather = 
        new OutputAttribute("WEATHER", "Your Weather Synopsis");        

private static Attribute[] stateAttr;        

static {       
   stateAttr = new Attribute[] {inPostCode, outWeather};    
}
        
@Override    
protected Attribute[] getStateAttributes() {       
   return stateAttr.clone();    
}

getStateAttributes is an abstract helper method that the SmappStatePlugin class implements. It aggregates both input and output variables. The base class derives the required getInputAttributes and getOutputAttributes methods from getStateAttributes, based on the attribute-type class. The state editor uses the attribute array that the getStateAttributes method returns to render input and output variables. The saveOutputAttributes method saves output attributes from the attribute array.

All variables (input and output) have input controls that appear on the state editor. The public String getText() method returns the text from input controls.

• Variables for Troubleshooting
  When you develop custom states, include error output variables that can help you troubleshoot problems in the production environment.
• Defining Input Variables
  States use input variables to get input values, either from a session variable or as a constant. You can configure the behavior in the state editor. The InputAttribute class manages input variables.
• Defining Output Variables
  States return results as output variables, which are always session variables. Only states can set output variables, and only at runtime. Output-variable check boxes are always selected and cannot be modified.
• Accessing Input Variables
  You can access input variables that are in a custom state using either the getInputValue method or the getInputValueWithWarning method.
• List Variables
  List variables do not appear in the state editor. You can use list variables to save lists of the BeanConverterInterface type to session variables.
• State Attributes Class Hierarchy
  All state variables that are derived from the Attribute class are identified by an ID and a description, which are defined in the constructor Attribute(String ID, String Description). ID is a unique identifier of the attribute; for InputAttribute, ID defaults to the session variable name. The value of the Description variable appears in the Application Composer.