Java Servlet Containers

Java Servlet Containers are the core runtime environments where Java web applications run. They manage the execution of Java Servlets, which are server-side components used to handle HTTP requests and responses.

What is a Servlet Container?

A Servlet Container (also known as a Web Container) is part of a web server or application server that interacts with Java Servlets. It provides the lifecycle management, multi-threading, security, and communication services required for running web applications based on Java EE (Jakarta EE) standards.

It is responsible for:

• Loading servlet classes.
• Creating and managing servlet instances.
• Handling requests and responses.
• Managing servlet lifecycle methods (init(), service(), destroy()).

Servlet Container Features

Some of the features are as follows:

• Request handling: Routes incoming HTTP requests to appropriate servlets.
• Lifecycle management: Manages servlet initialization, execution, and destruction.
• Session management: Tracks user sessions using cookies or URL rewriting.
• Security: Provides authentication, authorization, and HTTPS support.
• Concurrency: Handles multiple user requests using multithreading.
• Deployment: Supports deployment of .war (Web Application Archive) files.

Java Servlet Containers

Apache Tomcat

• Most popular open-source servlet container.
• Supports Servlets, JSP, and WebSocket.
• Lightweight and ideal for standalone web applications.

Jetty

• Lightweight and embeddable.
• Suitable for microservices and asynchronous processing.
• Often used in machine-to-machine communication.

GlassFish

• Full Jakarta EE (formerly Java EE) application server.
• Includes servlet container and other Java EE components (EJB, JPA, etc.).
• Suitable for enterprise applications.

WildFly (formerly JBoss AS)

• Developed by Red Hat.
• Robust, scalable, and full-featured Java EE server.
• Servlet container is part of a larger application server.

WebLogic Server

• Commercial offering by Oracle.
• Enterprise-level performance and scalability.
• Integrates with Oracle products.

WebSphere

• IBM’s enterprise-grade Java application server.
• Includes a servlet container and many enterprise features.
• Often used in large enterprise environments.

Servlet Container vs Application Server

Java Tutorial on this website:

• https://www.testingdocs.com/java-tutorial/