Agregar cabeceras usando el contexto actual en respuestas mediante struts2

AddHeadersToActionStruts.java

//Dependencias
import org.apache.struts2.StrutsStatics;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletResponse;

public String metodoprueba() throws Exception {
        final String origen = "loginAccion.metodoprueba";
        HttpServletResponse httpResponse =ServletActionContext.getResponse();
        httpResponse.setHeader("Access-Control-Allow-Origin", "*");
        httpResponse.setHeader("Access-Control-Allow-Methods", "POST, GET, PUT, OPTIONS, DELETE");
        System.out.println("---CORS Configuration Completed---");
        long time;
        String result = new String();
        result = "json";
        return result;
}