A Java web application is a software application that runs on a web server and is accessible to users through a web browser. Java web applications are built using Java and related technologies to create dynamic and interactive web-based systems. Here are the key components and steps involved in developing a Java web application:

1. Java Programming Language:

• Java serves as the core programming language for developing server-side components of the web application. Developers write Java code to handle HTTP requests, manage business logic, and interact with databases.

2. Servlets and JavaServer Pages (JSP):

• Servlets and JSP are key technologies in Java web development. Servlets handle HTTP requests and responses, while JSP allows embedding Java code within HTML templates to create dynamic web pages.

3. Web Frameworks:

• Java web applications often use web frameworks to streamline development. Popular frameworks include:
  • Spring Framework: Known for its modularity and wide range of features, Spring simplifies many aspects of web development, such as dependency injection, security, and database access.
  • JavaServer Faces (JSF): This Java EE standard provides a component-based approach to web development, simplifying user interface development.
  • Apache Struts: Struts is known for its MVC (Model-View-Controller) architecture, making it suitable for building large-scale applications.

4. Database Integration:

• Java web applications typically interact with databases to store and retrieve data. Developers use Java Database Connectivity (JDBC) or Object-Relational Mapping (ORM) frameworks like Hibernate to manage database operations.

5. Front-End Technologies:

• HTML, CSS, JavaScript, and popular JavaScript libraries/frameworks (e.g., React, Angular, or Vue.js) are used for creating the user interface and enhancing user experience.

6. Application Servers:

• Java web applications are deployed on application servers or servlet containers. Common choices include Apache Tomcat, Jetty, WildFly, and IBM WebSphere.

7. RESTful Web Services:

• Java web applications often expose RESTful web services for communication with other applications or clients. Libraries like JAX-RS (Java API for RESTful Web Services) or Spring REST are used to create RESTful APIs.

8. Security:

• Java provides built-in security features, and frameworks like Spring Security are used to manage authentication, authorization, and protection against security vulnerabilities.

9. Testing:

• Automated testing using frameworks like JUnit, TestNG, and Selenium is essential for ensuring the reliability and quality of Java web applications.

10. Deployment and Hosting: – Deploying a Java web application involves packaging it into a deployable format (e.g., WAR file) and configuring the application server.