Servers

https://www.youtube.com/watch?v=Nu-18s6EeM8

https://www.youtube.com/watch?v=ATObcDPLa40

https://www.javatpoint.com/server-web-vs-application

What is Tomcat?

Apache Tomcat is an open-source web server and servlet container for rendering Java Server Pages (JSPs) and executing servlets. Web applications can be deployed to a Tomcat server using WAR files (Java web archive files). Tomcat does not support the full EE stack and will not deploy EAR files.

If you don’t have a place to run your Tomcat yet, you can check out JavaPipe’s Java web hosting offers and see if that’s what you’re looking for. For now let’s proceed on how to setup your own Tomcat container.

https://stackoverflow.com/questions/29397202/does-glassfish-server-consist-of-a-webserver-also

Does Glassfish server consist of a webserver also?

1

According to the defintions I have read a web server is something which can serve http requests (e.g Apache).

A web container is something which can serve servlets and JSPs etc. Since Tomcat can both serve http requests and also serve servlets and JSPs it is considered as both a web server and a web container.

Application servers like Jboss, Glassfish are fully fledged java EE servers which also include other containers apart from the web container.

Now in order for an application server like Glassfish to work on its own, it also needs a web server(an http server) built into it. Therefore it should contain a webserver to work on its won, and if it doesn't contain a webserver built into it, there should be a way to plug existing web servers like apache to this application server.

What is the actual implementation? does it include a webserver or we should plug webservers into these java EE application servers?

1 Answer

1

Yes, it includes a full web tier. The Java Servlet spec covers much of this.

Most of the times these terms Web Server and Application server are used interchangeably.

Following are some of the key differences in features of Web Server and Application Server:

• Web Server is designed to serve HTTP Content. App Server can also serve HTTP Content but is not limited to just HTTP. It can be provided other protocol support such as RMI/RPC
• Web Server is mostly designed to serve static content, though most Web Servers have plugins to support scripting languages like Perl, PHP, ASP, JSP etc. through which these servers can generate dynamic HTTP content.
• Most of the application servers have Web Server as integral part of them, that means App Server can do whatever Web Server is capable of. Additionally App Server have components and features to support Application level services such as Connection Pooling, Object Pooling, Transaction Support, Messaging services etc.
• As web servers are well suited for static content and app servers for dynamic content, most of the production environments have web server acting as reverse proxy to app server. That means while servicing a page request, static contents (such as images/Static HTML) are served by web server that interprets the request. Using some kind of filtering technique (mostly extension of requested resource) web server identifies dynamic content request and transparently forwards to app server

Example of such configuration is Apache Tomcat HTTP Server and Oracle (formerly BEA) WebLogic Server. Apache Tomcat HTTP Server is Web Server and Oracle WebLogic is Application Server.

In some cases the servers are tightly integrated such as IIS and .NET Runtime. IIS is web server. When equipped with .NET runtime environment, IIS is capable of providing application services.

https://www.futurehosting.com/blog/jboss-vs-tomcat-choosing-a-java-application-server/

JBoss vs. Tomcat: Choosing A Java Application Server

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Picking between the various Java application servers can be a challenge for developers who are new to developing online Java apps and Java-based sites. The big three are Tomcat, Glassfish, and JBoss. All of them are excellent platforms upon which develop and deploy applications, but they have different strengths. Making the wrong choice can result in more work than necessary, so we’re going to cut through the confusion with a quick guide to which application server will best suit your needs.

In 2013, JBoss received a name change and is now known as WildFly, but the old name is still widely used, especially by those using the older versions, so, we’ll stick to calling it JBoss for the moment.

What is JBoss?

Developed by JBoss – a subsidiary of Red Hat Inc. – the JBoss Application server acts as an open-source alternative to solutions such as IBM WebSphere and SAP NetWeaver. It chiefly relies upon Sun Microsystems’ Enterprise JavaBeans API for functionality. Like most systems developed on EJB, it is designed to allow developers to focus primarily on the business architecture of the server, rather than getting bogged down in unnecessary programming and coding to connect the different working parts.

In addition to providing JBoss and all its associated middleware free of charge, Red hat operates a Developer Program that allows subscribers to gain direct access to exclusive content and product-focused forums. This program, too, is available free of charge, and exists primarily to drive JBoss development and foster a positive developer community. Developers are encouraged to participate on the official boards, contributing code and reporting issues wherever they crop up.

Lightweight and cloud-friendly, JBoss is powerful enough for use in enterprise, and features a middleware portfolio to help accelerate application development, deployment, performance, data integration, and automation. The JBoss website features extensive developer materials, training courses, and informational documents for both new and veteran devs.

What is Tomcat?

Often referred to as “Apache Tomcat,” Tomcat is not technically an application server at all – a fact which generates some confusion amongst first-timers, as ‘application server’ and ‘web server’ are all too often used interchangeably.

Rather, Tomcat is more of a web server and web container. This does not mean it lacks functionality, mind you. An open-source implementation of the Java Servlet, JavaServer Pages, Java Expression Language, and Java WebSocket Technologies, it is intended as a platform for powering large-scale, mission-critical web applications. It is used by major enterprises across several industries and verticals, including development, finance, healthcare, government, ecommerce, retail, and marketing.

As with JBoss, Tomcat’s core developers strongly encourage community participation in the evolution of their platform. They host an extensive development community, with thorough documentation and an active support forum. Apache also maintains a mailing list with updates, tips and tricks, and information on Tomcat.

The Major Differences Between JBoss and Tomcat

Both JBoss and Tomcat are Java servlet application servers, but JBoss is a whole lot more. The substantial difference between the two is that JBoss provides a full Java Enterprise Edition (JEE) stack, including Enterprise JavaBeans and many other technologies that are useful for developers working on enterprise Java applications. Tomcat is much more limited. One way to think of it is that JBoss is a JEE stack that includes a servlet container and web server, whereas Tomcat, for the most part, is a servlet container and web server.

That said, it can also run enterprise applications, a fact which causes no small amount of confusion.

“Many application developers do not focus much on the infrastructure on which their code runs,” writes Manu PK of The Java Zone. “When it comes to web applications, the difference between web servers and application servers [is a common confusion]…Typically, we get confused when [we see that] Tomcat [has] the ability to run enterprise applications.”

When To Choose JBoss

JBoss is the best choice for applications where developers need full access to the functionality that the Java Enterprise Edition provides and are happy with the default implementations of that functionality that ship with it. If you don’t need the full range of JEE features, then choosing JBoss will add a lot of complexity to deployment and resource overhead that will go unused. For example, the JBoss installation files are around an order of magnitude larger than Tomcat’s.

When To Choose Tomcat

Tomcat is a Java servlet container and web server, and, because it doesn’t come with an implementation of the full JEE stack, it is significantly lighter weight out of the box. For developers who don’t need the full JEE stack that has two main advantages.

• Significantly less complexity and resource use.
• Modularity.

There are numerous providers of add-ons that work with Tomcat. Developers can choose the specific implementations they want to use to add extra functionality. For example, Tomcat can’t natively host Enterprise JavaBeans. However, if users need Enterprise JavaBeans (EJB) functionality like the persistence and transaction processing that the EJB container model provides, but want to avoid the problems inherent in the main implementation, there are many lightweight alternatives, including the Spring Framework and OpenEJB

Developers of complex Java enterprise applications should choose JBoss (or GlassFish), while those who don’t need the full JEE stack are better off with Tomcat plus any extensions they need.

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How to deploy Spring Boot Web App War file to Tomcat Server with Maven build

https://www.youtube.com/watch?v=n7k20TTfPOI

Deploying Spring Boot App to JBoss Wildfly

We know that when we create any Spring Boot application, it comes with an embedded Tomcat server, and we have no need to set up the server additionally. This happens because, in the Spring Boot parent project, it has the dependency for Tomcat, and when we start the Spring Boot application, it bootstraps the application with the Tomcat server itself.

You may also like:  Welcome to Spring Boot (With Embedded Tomcat Features)

But sometimes, our requirements might include creating a war file and then deploying it to any web application server, like JBoss. In this article, we will see how to package a Spring Boot application and deploy it to any external server. Here, we will be using JBoss to perform the following tasks:

• Create a Spring Boot application
• Remove the embedded Tomcat server from the application
• Generate a war file that can be deployed to the JBoss server

Creating a Spring Boot Application

• You can create a Spring Boot application by generating a project from start.spring.io.
• Once downloaded, you can import the Maven project to your IDE (Spring Tool Suite is recommended) as an existing Maven project.
• Then, implement a Maven build to fetch the required dependencies.

Separate the Embedded Tomcat Server From the Spring Boot App

• First of all, open the pom.xml and add the Tomcat dependency. Next, you can change the scope to the provided. When we make the scope as provided that means this dependency will be available during compile time only and will not be available at run-time. This is because we need this dependency in compile time to compile the web-component-related files.
• Adding the Tomcat dependency and changing the scope to provided will give us the following:

<dependencies>

    <dependency>

        <groupId>org.springframework.boot</groupId>

        <artifactId>spring-boot-starter-tomcat</artifactId>

        <scope>provided</scope>

    </dependency>

</dependencies>

<!-- Make sure that you changed the packaging to war -->

 <packaging>war</packaging>

• Then, extend the SpringBootServletInitializer class in your Spring Boot main class and override the configure method. We need to do this to initialize the application in any other servlet container like JBoss.
• You can see the code below that extends the SpringBootServletInitializer and overrides the configure method.

@SpringBootApplication

@EnableSwagger2

public class SpringBootDemoApplication extends SpringBootServletInitializer {

  @Override

  protected SpringApplicationBuilder configure(SpringApplicationBuilder builder){

    return builder.sources(SpringBootDemoApplication.class);

  }

  public static void main(String[] args){

    SpringApplication.run(SpringBootDemoApplication.class, args);

  }

}

• With this configuration, the application is ready to deploy to any external application server.
• Once this is done, you can package your Spring Boot application as a war and deploy it to the JBoss server. To do that, you need to run  mvn clean package, which will generate the war file.

That's all for now. We hope you enjoyed this short demonstration. Be sure to leave thoughts and questions in the comments section.

Further Reading

Welcome to Spring Boot (With Embedded Tomcat Features)

Introducing Spring Boot

[DZone Refcard] Getting Started With JBoss