struts2 setter & getter

When invoking the action, the default configuration (with default interceptor stack) maps the http parameters calling the setter. Ej, if you call http:/..../myAction.action?myval=xx Struts2 will instance your action and call the method setMyval("xx") (if your property is not a string, struts2 will try to convert it).

After the action execution, when the results are displayed in the view (say,a JSP page), you might write <s:property value='myval' /> and Struts2 will invoke the method getMyval() of your action.