Explain the architecture and components of Java servlets and their role in web application development.

Java servlets are server-side components that provide a dynamic, platform-independent approach to web application development. They are an essential part of the Java Enterprise Edition (Java EE) platform and play a crucial role in handling client requests and generating dynamic responses. Let's explore the architecture and components of Java servlets in detail:

1. Servlet Architecture:
The architecture of Java servlets follows the Model-View-Controller (MVC) pattern, where servlets act as the controller component. The servlet container, typically provided by a Java EE application server, manages the lifecycle and execution of servlets. When a client sends a request to a web application, the servlet container receives the request and delegates it to the appropriate servlet for processing. The servlet then generates a response, which is sent back to the client.
2. Servlet Interface:
The core component of a servlet is the Servlet interface, defined by the Java Servlet API. This interface defines methods that servlets must implement to handle client requests and generate responses. The primary methods include:

* `init()`: This method is called by the servlet container to initialize the servlet before it starts handling requests. It is typically used for one-time setup tasks.
* `service()`: This method is invoked for each client request and is responsible for processing the request and generating the response. It receives two parameters: a ServletRequest object representing the client request and a ServletResponse object for generating the response.
* `destroy()`: This method is called by the servlet container when the servlet is being shut down. It allows the servlet to perform any necessary cleanup tasks.
3. HttpServlet:
The HttpServlet class is an abstract class that extends the Servlet interface and provides additional functionality specifically for HTTP-based web applications. It simplifies the handling of HTTP methods (such as GET, POST, etc.), request parameters, session management, and more. Developers typically extend the HttpServlet class to create their servlets, overriding its methods to customize the handling of HTTP requests.
4. Servlet Configuration:
Servlets can be configured using deployment descriptors, such as the web.xml file or annotations. These configurations specify the URL mappings that associate servlets with specific client requests, initialization parameters, security constraints, and other settings. Configurations help in defining the behavior and characteristics of servlets within the web application.
5. Servlet Context:
The ServletContext interface provides a way for servlets to communicate with the servlet container and access shared resources. It represents the context of the web application and allows servlets to share data, access configuration information, manage sessions, and perform other application-level operations.
6. Request and Response Objects:
Servlets receive client requests through the ServletRequest object, which provides access to request parameters, headers, cookies, and other request-specific information. Servlets generate responses using the ServletResponse object, which allows setting response headers, writing content, and managing cookies. These objects encapsulate the client-server communication and enable servlets to handle diverse types of requests and generate dynamic responses.
7. Servlet Filters:
Servlet filters are components that intercept and modify requests and responses before they reach the servlet or are sent back to the client. Filters provide functionalities such as logging, authentication, input validation, and data compression. They can be configured to apply to specific servlets, URL patterns, or the entire web application, allowing for modular and reusable functionality.
8. Session Management:
Servlets can manage user sessions using the HttpSession interface. Sessions enable storing and retrieving session-specific data across multiple requests, facilitating stateful interactions with clients. Servlets can create, retrieve, and invalidate sessions, store and retrieve session attributes, and handle session-related events.

In summary, Java servlets form a critical part of web application development in Java. They provide a server-side component that receives and processes client requests, generates dynamic responses, and interacts