In-depth discussion of the principles and practices of the Struts framework

Principle analysis and practical exploration of the Struts framework

As a commonly used MVC framework in Java Web development, the Struts framework has good design patterns and Scalability, widely used in enterprise-level application development. This article will analyze the principles of the Struts framework and explore it with actual code examples to help readers better understand and apply the framework.

1. Analysis of the principles of the Struts framework

1. MVC architecture

The Struts framework is based on the MVC (Model-View-Controller) architecture and divides the application into models (Model) , View and Controller to achieve the separation of data, display and business logic. Among them:

• Model: Responsible for processing data encapsulation and business logic processing, usually JavaBean objects or database operations.
• View: Responsible for displaying data to users, usually a JSP page or HTML page.
• Controller: Responsible for receiving the user's request and calling the corresponding business logic according to the request, and then returning the processing result to the View.

2. Core components of the Struts framework

The core components of the Struts framework include Action, ActionForm, ActionMapping, ActionServlet, etc. They work together to implement request processing and page jumping of Web applications. change.

• Action: The core component that handles user requests, responsible for receiving HTTP requests, calling business logic and returning results.
• ActionForm: Form data encapsulation class, responsible for encapsulating form data submitted by users into JavaBean objects.
• ActionMapping: The mapping relationship between Action and request URL, which defines the Action objects corresponding to different request paths.
• ActionServlet: The Servlet container loads the control center of the Struts framework, initializes the Struts framework and distributes requests to the corresponding Action for processing.

2. Practical exploration of the Struts framework

In order to better understand the practical application of the Struts framework, we take a simple login page as an example to demonstrate how to use the Struts framework to Login processing. The following is a specific code example:

1. Write the login page (login.jsp)

<form action="login.do" method="post">
    <input type="text" name="username" placeholder="用户名">
    <input type="password" name="password" placeholder="密码">
    <input type="submit" value="登录">
</form>

2. Write the Action class (LoginAction)

public class LoginAction extends Action {
    public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception {
        LoginForm loginForm = (LoginForm) form;
        String username = loginForm.getUsername();
        String password = loginForm.getPassword();

        if("admin".equals(username) && "123456".equals(password)) {
            return mapping.findForward("success");
        } else {
            return mapping.findForward("error");
        }
    }
}

3. Write the Form class (LoginForm)

public class LoginForm extends ActionForm {
    private String username;
    private String password;

    // getter和setter方法省略
}

4. Configure the Struts configuration file (struts-config.xml)

<action-mappings>
    <action path="/login" type="LoginAction" name="LoginForm" input="/login.jsp" scope="request">
        <forward name="success" path="/success.jsp"/>
        <forward name="error" path="/error.jsp"/>
    </action>
</action-mappings>

Through the above steps, we have implemented a simple user login function. When the user logs in After entering the user name and password on the login.jsp page, click the login button and send the request to /login.do. The LoginAction class handles the login logic and based on the user name and password The verification result jumps to a different page.

Conclusion

Through the analysis and practical exploration of the principles of the Struts framework, this article hopes that readers can have a more in-depth understanding of the working principles and application scenarios of the framework. In actual project development, the reasonable use of the Struts framework can improve development efficiency and reduce maintenance costs. It is one of the indispensable and important tools in Java Web development.

The above is the detailed content of In-depth discussion of the principles and practices of the Struts framework. For more information, please follow other related articles on the PHP Chinese website!