Struts are mainly considered as a legacy and if it is needed very much by the client, we should follow the same. This framework is popular due to ease of use and knowledge of Java by developers. This is a guide to the Struts Framework. Here we discuss the introduction, Framework, and advantages of Struts in detail.
You may also look at the following articles to learn more —. Submit Next Question. By signing up, you agree to our Terms of Use and Privacy Policy. Forgot Password? The Action object processes requests using its execute method, while making use of any data stored in the form bean. Once the Action object processes a request, it stores any new data i. However, you complement your web development toolkit by taking advantage of the Struts support provided by the IDE. Upon creation, the IDE automatically registers these classes in the struts-config.
The following steps demonstrate how to create a simple form that collects user data, performs simple validation, and outputs the data on a success page. In the IDE, a Struts application is nothing more than a normal web application accompanied by the Struts libraries and configuration files. You create a Struts application in the same way as you create any other web application in the IDE - using the New Web Application wizard, with the additional step of indicating that you want the Struts libraries and configuration files to be included in your application.
Click Next. In the Server and Settings panel, select the server to which you want to deploy your application. Only servers that are registered with the IDE are listed. To register a server, click Add next to the Server drop-down list. For purposes of this tutorial, do not change any of the configuration values in the lower region of this panel.
The wizard displays the following configuration options. Action Servlet Name : The name of the Struts action servlet used in the application. The web. This generates a mapping entry in the deployment descriptor.
Application Resource : Lets you specify the resource bundle which will be used in the struts-config. By default, this is com. A tag library descriptor is an XML document which contains additional information about the entire tag library as well as each individual tag.
Click Finish. The IDE creates the project folder in your file system. However, your web application in addition has all of the Struts libraries on its classpath. The project opens in the IDE. The Projects window is the main entry point to your project sources. It shows a logical view of important project contents. For example, if you expand several nodes within the new project, it may appear as follows:. Open the deployment descriptor double-click the web.
In order to handle Struts processing, a mapping is provided for the Struts controller servlet. Above, the Struts controller servlet is named action and is defined in the Struts library org. In addition, initialization parameters for the servlet are specified by means of the struts-config. Begin by creating two JSP pages for the application.
The first displays a form. The second is the view returned when login is successful. The login. You can also invoke code completion manually by pressing Ctrl-Space:. The bean taglib provides you with numerous tags that are helpful when associating a form bean i.
The html taglib offers an interface between the view and other components necessary to a web application. Whenever you finish typing in the Source Editor, you can tidy up the code by right-clicking and choosing Format Alt-Shift-F. The Insert Table dialog box displays. Set the rows to 3 , columns to 2 , and leave all other settings at 0. Later in the tutorial, you will attach a stylesheet to affect the table display. The form in login. The html:text element enables you to match the input fields from the form with properties in the form bean that will be created in the next step.
So for example, the value of property must match a field declared in the form bean associated with this form. In order for success.
Add a bean taglib directive to the top of the file:. A Struts ActionForm bean is used to persist data between requests. For example, if a user submits a form, the data is temporarily stored in the form bean so that it can either be redisplayed in the form page if the data is in an invalid format or if login fails or displayed in a login success page if data passes validation. Type in LoginForm for the Class Name.
Then select com. By default, the IDE provides it with a String called name and an int called number. Both fields have accessor methods defined for them. Also, the IDE adds a bean declaration to the struts-config. If you open the struts-config. In the initialization phase, the controller rectifies a configuration file and uses it to deploy other control layer objects.
Struts in Java configuration is formed by these objects combined. The struts configuration defines, among other things, the action mappings for an application. Struts controller servlet considers the action mappings and routes the HTTP requests to other components in the framework.
The request is first delivered to an action and then to JSP. The mapping helps the controller to change HTTP requests into application actions. The action objects can handle the request form and respond to the client generally a web browser. When delivering the control, an action object can indirectly forward one or more shared objects, including JavaBeans, by establishing them in the typical situation shared by java servlets.
In Struts 2, an interceptor is a type of object which is invoked at the preprocessing and postprocessing of a request. In interceptors, the user has to remove the entry from the struts. If the user wants to remove validation, exception handling or any other concern from any applications, then the user does not need to adjust the application.
Struts 2 provides many interceptors and the users have a choice to create their own interceptors. So these are-. Dispatch action is a concept that is used to implement the concept of multiple method definitions inside the action.
It means dispatch action provides the facilities to execute a method among the multiple methods of the same action to process the request. Generally, dispatch action is used if the action class contains logically related functionalities.
Suppose 10 clients work at the same time for a particular action, then 10 objects are created in the value stack. This is because it is a single thread for every 10 threads. It is not multi-threading. OGNL is an object graph navigation language. It helps in type conversion and expression language. It is more powerful as it can also invoke methods in java using expression language. OGNL has form tags to generate the form and to point the bean and field in which the values have to be set.
It also has UI tags to display the results from various types like arrays, collections etc. OGNL also takes care of the type conversion to set the form values to the beans from primitive or custom types to string. This brings us to the end of the blog on Struts in Java. We hope that you were able to grasp the concept well. Remember Me! Great Learning is an ed-tech company that offers impactful and industry-relevant programs in high-growth areas.
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