A Java framework can be defined as a pre-written code in Java that can be used as a template or skeleton by developers when building an application. It can be used and reused in creating a new application, which prevents you from having to write the entire code from scratch. By defition, a Java framework is specific to Java programming alone and cannot be used by any other language (although there are equivalents in other languages, like PHP).
A Java framework typically includes predefined classes or functions that can be used to develop a software application. The usage of these frameworks is quite dependent on the skill of the programmer, the requirements of the application, and the preferences of the developer.
A framework often dictates the structure of an application. There are some frameworks that will mostly do all the work for you, whhich means you have to write very little code. Choosing the right framework is critical because of this. If you choose a good framework, your program will be robust. If you choose a bad one, your program may be prone to failures.
Benefits of Java Frameworks
There are a number of benefits to using a framework when building a Java application:
The biggest advantage of using a Java framework is security. A good framework has secure components and if you find any vulnerability in it, you can always ask the developers to fix the issue. In fact, many frameworks are open source, which means you can actually contribute these improvements yourself.
Popular frameworks have large support groups that can help in resolving any issues or answering any questions that you might have. The documentation part can help you understand the framework before you use it.
Using Java frameworks to develop a code or an application can improve the efficiency of the task by reducing the time you take to develop the code.
While Java frameworks do cost you money, the expenses are quite lower than what you encounter while developing the code from scratch. Using Java frameworks reduces the time taken and effort, and therefore, bring down the cost.
10 Best Java Frameworks
While there are a plethora of frameworks built on Java, here I will discuss the 10 most commonly used frameworks along with little insight into what makes them popular.
Spring is a lightweight but powerful application development open-source framework that is used for Enterprise Java (JEE). Spring introduced the concept of dependency injection (DI) and aspect-oriented programming. Developers can use Spring to create loosely coupled modules. With Spring, the dependencies are handled by the framework and not the libraries in the code.
The Spring framework is exhaustive and includes a number of features. The core features of Spring are used in developing any Java application. Also, it can be used for the all-layer implementation of a real-time application.
The Spring framework and all its modules are used in enterprise applications. The main concepts that it is built on are:
* Dependency Injection (DI):
In this concept, instead of the application taking control of the flow sequentially, it is driven by an external controller. Whenever any event happens, the flow continues. This gives flexibility to the application. There are three types of Dependency Injections: setter injection, method injection, and constructor injection.
* Beans and Spring Context:
Objects are referred to as beans in Spring. The beans are managed and configured by a BeanFactory. Most applications implement XML for configuration. For more complex applications, ApplicationContext (a superset of BeanFactory) is used. These are applications that need event propagation, declarative mechanisms, and integration with aspect-oriented features of spring.
Hibernate is a stable object-relational mapping framework for Java. It gives a new perspective into a database. Hibernate can be understood as an Object-Relational-Mapping (ORM) database for Java applications. The queries in Hibernate are written in HQL (Hibernate Query Language). It improves the communication between the Java language and the relational database management systems (RDBMS).
While working with Java, you may encounter a problem called Object-Relational Impedance Mismatch, also referred to as the Paradigm Mismatch. This is because the RDBMS and the object-oriented languages handle data differently, which can lead to mismatch problems. Hibernate offers solutions to this issue. It directly maps the Java classes to corresponding database tables and vice versa. Hibernate has an abstraction layer that helps the code to be loosely coupled with the database. It also handles operations like establishing database connections and writing CRUD operations.
Apache Struts is a very robust open-source framework used for web applications. An enterprise-level framework, Struts allows you to easily create modern Java applications.
Struts follows the model-view-controller (MVC) model and extends the JSP API. There are two versions of this framework: Struts 1 and Struts 2. Struts 2 is preferred being the updated version.
Struts separates the view, controller and model and binds them together through a configuration file. The struts framework is quite easy to set up and offers a lot more flexibility and extensibility as compared to the traditional MVC approach. Struts can be a good start if you are looking at a career in web development with Java.
Google Web Toolkit (GWT)
GWT helps developers create complex browser applications with ease and allows development and debugging of Ajax applications in Java.
Java Server Faces (JSF)
Developed by Oracle, JavaServer Faces (JSF) is used for creating Java-based web applications. It is a stable and component-based UI framework. JSF is based on MVC and is an important part of Java EE. It comes with great tools and rich libraries that makes it easy to build sophisticated applications.
Grails is the right choice for those who are looking to start their programming career. It is a web framework written in the Groovy programming language that runs on the Java platform and is compatible with Java Syntax. It works well with Java technologies like Java EE containers, Spring SiteMash, and Hibernate.
Grails is considered very developer-friendly since it is supported by documentation. The best part is that you can integrate existing Java code with Grails. Most e-commerce sites written in Java use Grails for their framework.
Dropwizard is known to be a high-performance Java framework that can be used to create RESTful web applications. Dropwizard is suitable for creating Java microservices.
Dropwizard provides a fast and distraction-free development platform by bringing together libraries like Jetty, Guava, Jersey, Jackson, and Metrics that results in a very lean application. It is a separate ecosystem altogether with dependencies bundled into a single package.
All you need to do as a developer is build your business logic because the rest of the work related to performance, security, and configurations is taken care of by the integrated libraries included with Dropwizard.
The Java Play framework is a reactive framework that is used to build highly scalable Java applications. Using Play, it is possible to develop web-friendly and light applications for both desktops and mobile interfaces.
Play does not depend on Java EE standards. Instead, it removes all inconveniences associated with traditional Java web development like extensive configurations and slow development cycles. It is similar to Django and Ruby on Rails and does not follow any J2EE web standards. It delivers high performance because of asynchronous processing. It uses statically-typed language, therefore, most of the errors are caught and removed early in the development cycle.
ATG is a web commerce customizable platform in Java that is useful in creating e-commerce websites.
Owned by Oracle, ATG supports B2B and B2C applications alike. It runs on three servers: Oracle Weblogic, IBM Websphere, and JBoss. The three main layers of ATG are:
* The Dynamo Application Framework:
It is the base layer that provides a development environment powered by JSP and JavaBeans. It has standard ATG classes for all the basic functionalities.
* The Personalization Module:
This is the layer where the content for every user is customized dynamically. It allows the controlling and maintenance of user-profiles and business rules.
* The Scenarios Module:
The scenarios module introduces time-sensitive and event-driven campaigns to further enhance the personalization features.
It is an extensive framework and requires a lot of time and effort to learn. Some examples of websites built on ATG include Walmart, Macy’s, and BestBuy.
Vaadin is a web application framework that focuses on user experience (UX) accessibility. It allows streamlined Java development and also offers a platform to build applications of customizable components.
Vaadin is the framework that allows automated communication between the browser and the server. The core of this framework is web components.
Vaadin offers a new approach to building Java applications so that you can focus on the presentation without having to worry about communication between client and server. It also contains Data Binding APIs that map UI components to the database using type-safe Java code and abstraction layers.
There's a tremendous number of Java frameworks available for development today. Choosing the right framework comes down to your business requirements and the level of flexibility and optimal performance that you need.
In this tutorial, I discussed the 10 best Java frameworks for software development in 2020. Regardless of your project, you should be able to find a framework in this list to meet your needs.