Every software developer working with Java learns both the usefulness and complexity of the language. While it’s flexibility makes it one of the most popular programming languages available, finding ways to use Java to its full potential can prove daunting to many coders.
Into this world comes the Spring framework, a tool to help both simplify Java programming and expand its scope. A popular J2EE (Java 2 Enterprise Edition) framework, Spring offers an array of modules to smooth out the bumps in developing applications. The configuration model Spring provides is too good to be ignored for Java programmers.
While we will take a look at some of the strengths of Spring, none of this will make much sense if you do not already have a strong working knowledge of Java, which you can start learning on our Java Learn page.
Now, let’s take a leap into Spring.
4 Useful Things To Help You Understand the Spring Framework.
1. What is it?
The first step is to define the Spring framework. Beware, a beginner may get easily confused the first time they encounter Spring, so take your time while exploring it. For many in the programming world, it’s worth the effort.
In layman’s terms, the Spring framework helps to link different components of the application. J2EE applications are composed of multiple components stitched together, and care must be taken to avoid unnecessary complexity. Anyone who has worked with Java already knows that everything is considered an object. Spring acts as a bridge between objects and helps decrease their dependency on each other.
At the core of this is Spring’s IoC (Inversion of Control) container which, while not necessary for using all parts of the framework, is a great aid in configuring and managing the Java objects Spring creates, which are also called “beans”.
According to a StackExchange explanation of dependency injection,
“Design your objects so that they rely on an outside force to supply them with what they need, with the expectation that these dependencies are always injected before anybody asks them to start doing their usual jobs.”
Hence, the load is taken away from objects, keeping the system clean and working together. Many Java programmers confuse how the Spring framework works, and miss its true potential.
2. Spring helps you get rid of excessive code
Many J2EE applications contain unnecessary amounts of “plumbing code” – like having too many pipes in a building. By helping remove this excess, Spring helps you streamline your code. Resources spent on maintenance is also decreased or can even reach zero.
3. BeanFactory
To achieve its goals, Spring uses BeanFactory. In Spring, the BeanFactory is a generic factory that manages object relationships and also helps objects to easily be retrieved using object name.
So, what does that exactly do for a programmer? A programmer can use BeanFactory to write the configuration and specifications in different places. This decoupling effect is what makes the Spring framework useful. Also, BeanFactory is a container type and offers the ability to manage different beans at the same time. For example, you can configure and manage many beans and offer collaboration between each other, creating the base for a Spring application.
4. It is mostly XML
The Spring framework uses a lot of XML content for configuration. Below is an example of a BeanFactory configuration.
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<?xml version="1.0" encoding="UTF-8"?> <!--DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd"> <beans> <bean id="..." class="..."> ... </bean> <bean id="..." class="..."> ... </bean> ... </beans> |
The above code is a configuration file. However, you need to initialize the BeanFactory object to really do anything. Below is the code to initialize a BeanFactory object.
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ApplicationContext appContext = new FileSystemXmlApplicationContext("classpath:springconfig.xml"); BeanFactory factory = (BeanFactory) appContext; |
Conclusion
The Spring framework is a must for anyone who is dealing with a lot of complexity in their J2EE applications. If you are new to Spring, you can get started by checking the Spring Learn page. Check out the videos listed under Beginner, Intermediate, and Expert.
You can also check out micheljung on how he uses Spring framework.
Do you have anything to add to the list? Comment below and let us know!