Is Tomcat a Web Server or an Application Server?
When it comes to Java web application development, understanding the difference between a web server and an application server is essential. One commonly used server in the Java ecosystem is Apache Tomcat.
However, there is often confusion about whether Tomcat is a web server or an application server. Let’s delve into this topic and clear up any misconceptions.
Web Servers
A web server primarily handles the HTTP protocol and serves static content such as HTML, CSS, images, and JavaScript files to clients upon request. It responds to client requests by sending back the requested files over the network. Examples of popular web servers are Apache HTTP Server and Nginx.
Application Servers
An application server, on the other hand, provides a runtime environment for deploying and executing dynamic applications. It supports multiple protocols, such as HTTP, RMI (Remote Method Invocation), IIOP (Internet Inter-ORB Protocol), etc., allowing communication between clients and applications. Application servers offer various services like connection pooling, transaction management, security enforcement, and distributed computing.
Tomcat: A Web Server or an Application Server?
Now that we understand the basic definitions of web servers and application servers, we can address the question: Is Apache Tomcat a web server or an application server?
Apache Tomcat, commonly referred to as just “Tomcat,” was initially developed as a pure Java implementation of the Java Servlet Specification – which makes it a servlet container. A servlet container provides an environment for running Java servlets, which are components responsible for handling incoming requests and generating responses based on those requests.
However, over time, Tomcat has evolved to offer additional functionalities. Apart from being a servlet container, it also provides support for JavaServer Pages (JSP), WebSocket, and Java API for WebSocket. This expansion has led to some confusion regarding its classification.
Tomcat as a Web Server
Although Tomcat is not a full-fledged web server like Apache HTTP Server, it can function as a web server. By incorporating the Apache Portable Runtime (APR) library or the Java Native Interface (JNI), Tomcat can efficiently handle static content and serve files over the HTTP protocol.
Tomcat as an Application Server
In terms of application server capabilities, Tomcat falls short compared to heavyweight application servers like Red Hat JBoss or IBM WebSphere. While Tomcat does provide some additional features beyond servlet support, such as managing sessions and handling JSPs, it lacks enterprise-level services like EJB (Enterprise JavaBeans) or distributed transactions.
The Bottom Line
To sum up, Apache Tomcat can be considered both a web server and an application server depending on how it is utilized. It excels as a servlet container and can function as a lightweight web server for serving static content. However, if you require extensive enterprise-level services, you may need to look into using a more robust application server alongside or instead of Tomcat.
In conclusion, understanding the distinction between web servers and application servers is crucial in making informed decisions about your infrastructure requirements. Hopefully, this article has provided clarity on whether Tomcat is a web server or an application server and highlighted its capabilities in both domains.