Table of Contents
What is Struts 2 basic flow?
Struts 2 standard flow (Struts 2 architecture) Container maps the request in the web. xml file and gets the class name of controller. Container invokes the controller (StrutsPrepareAndExecuteFilter or FilterDispatcher). Since struts2.
How do you use annotations in Struts 2?
Annotations used in struts 2 application
- 1) @Action annotation is used to mark the action class.
- 2) @Results annotation is used to define multiple results for one action.
- 3) @Result annotation is used to display single result.
- Let’s have a look at the directory structure first.
What is Struts prepare and execute filter?
public class StrutsPrepareAndExecuteFilter extends Object implements StrutsStatics, javax.servlet.Filter. Handles both the preparation and execution phases of the Struts dispatching process. This filter is better to use when you don’t have another filter that needs access to action context information, such as Sitemesh …
What is filter Struts2?
In the web. xml file, Struts defines its FilterDispatcher, the Servlet Filter class that initializes the Struts framework and handles all requests. This filter can contain initialization parameters that affect what, if any, additional configuration files are loaded and how the framework should behave.
What is MVC architecture in Struts?
Struts is an open source framework that extends the Java Servlet API and employs a Model, View, Controller (MVC) architecture. It enables you to create maintainable, extensible, and flexible web applications based on standard technologies, such as JSP pages, JavaBeans, resource bundles, and XML.
What is the purpose of @results annotation *?
A Results annotation is a collection of results. The next annotation is the Action annotation. This is used to decorate the execute() method. The Action method also takes in a value which is the URL on which the action is invoked.
What is action invocation?
An ActionInvocation represents the execution state of an Action . It holds the Interceptors and the Action instance. By repeated re-entrant execution of the invoke() method, initially by the ActionProxy , then by the Interceptors, the Interceptors are all executed, and then the Action and the Result .
What is the purpose of @ExpressionValidator annotation?
ExpressionValidator Annotation – (Validation Annotation) This non-field level validator validates a supplied regular expression.
What types of validators are available in XML based validation in Struts2 *?
Struts2 XML based validation provides more options of validation like email validation, integer range validation, form validation field, expression validation, regex validation, required validation, requiredstring validation, stringlength validation and etc.
What is action servlet in Struts?
ActionServlet represents the “controller” in the Model-View-Controller (MVC) design pattern for web applications that is commonly known as “Model 2”. This nomenclature originated with a description in the JavaServerPages Specification, version 0.92, and has persisted ever since (in the absence of a better name).
What is FilterDispatcher in Struts2?
The FilterDispatcher ( org.apache.struts2.dispatcher.FilterDispatcher) is used in the early Struts2 development, and it’s deprecated since Struts 2.1.3.
Should I upgrade to the new filter class in struts?
If you are using Struts version >= 2.1.3, it’s always recommended to upgrade the new filter class – StrutsPrepareAndExecuteFilter ( org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter ). Founder of Mkyong.com, love Java and open source stuff.
How do you return a string from a struts action?
In Struts action method is executed after the the action’s properties are populated. The method in the action returns a String. Eg if it returns a “Success” , or “failure”, depending upon the return value it can be forwarded to the result page.
What is the work of the first interceptor in struts?
Eg the work of the first interceptor is to populate the action object with the request parameters. In Struts action method is executed after the the action’s properties are populated. The method in the action returns a String.