GlassFish vs Jetty: What are the differences?

Introduction In web development, GlassFish and Jetty are two popular Java-based application servers that are used for deploying and running web applications. Although they serve a similar purpose, there are several key differences between GlassFish and Jetty that developers should consider when choosing one for their projects.

1. Deployment Model: GlassFish is a full Java EE (Enterprise Edition) application server that provides a complete Java EE runtime environment, including all the APIs and services defined in the Java EE specification. On the other hand, Jetty is primarily a lightweight web server and Servlet container that focuses on providing a minimalistic and efficient environment for web application deployments. Unlike GlassFish, Jetty does not provide all the Java EE features and relies on integration with other technologies to achieve a full Java EE runtime.

2. Community and Support: GlassFish is an open-source project that is developed and supported by Oracle, which means it has a large community of contributors and users. This allows for regular updates, bug fixes, and a robust support system. Jetty, on the other hand, is also an open-source project, but with a smaller community compared to GlassFish. While it has active developers and a responsive support team, the level of community participation might be slightly lower than that of GlassFish.

3. Performance and Scalability: Jetty is known for its lightweight architecture and low memory footprint, which enables it to handle a high number of concurrent requests with minimal resource consumption. GlassFish, on the other hand, due to its full Java EE stack, tends to be more resource-intensive and may require more memory and processing power to handle the same amount of traffic. In scenarios where high performance and scalability are critical, Jetty might be a preferred choice.

4. Documentation and Configuration: When it comes to documentation and configuration, GlassFish provides comprehensive and detailed documentation, including step-by-step guides, tutorials, and examples. It also offers a graphical administration console that simplifies the configuration and management of server resources. Jetty, on the other hand, offers a more lightweight documentation set, with a focus on providing essential information for configuration and deployment. It also provides a simple XML-based configuration file that allows developers to fine-tune the server behavior.

5. Embeddability and Customization: Jetty is highly embeddable and can be easily integrated into other applications, which makes it a suitable choice for developers who need to embed a web server into their software stack. It allows for customizations and extensions at various levels and provides a flexible programming model. GlassFish, although it can be embedded to some extent, is primarily designed to be a standalone application server and might not offer the same level of embeddability and customization options as Jetty.

6. Technology Compatibility and Ecosystem: GlassFish is known for its strong compatibility with the Java EE specification and offers support for a wide range of Java EE technologies, such as JMS (Java Message Service) and JNDI (Java Naming and Directory Interface). It also has a larger ecosystem of third-party libraries and frameworks that are compatible with it. Jetty, while not offering the same level of out-of-the-box compatibility with Java EE, has its own set of technologies and integrations, which make it suitable for specific use cases and environments.

In Summary, GlassFish is a full Java EE application server, while Jetty is a lightweight web server and Servlet container. GlassFish offers a complete Java EE runtime environment, has a larger community and support system, but is more resource-intensive. Jetty is known for its scalability and performance, provides lightweight documentation, is highly embeddable, and has a smaller community.