Spring Interview Questions

Spring Interview Questions and Answers

This is a review of some of the common vital questions about the Spring Framework, which you may be asked in an interview or in an interview examination procedure! There is no need to worry for your subsequent interview test because we are here to help you.The most of the questions you may be asked is assembled below. All core modules, from basic Spring functionality as Spring Beans, up to Spring MVC structure are introduced and explained in brief.

So, let’s go…!

Spring summary

What is Spring?

answer.Spring is an open reference development framework for Enterprise Java. The core characteristics of the Spring Framework can be utilized in improving any Java application, but there are expansions for building web applications on top of the Java EE platform. Spring framework aims to create Java EE development simpler to use and develop good programming system by allowing a POJO-based programming model.

What are advantages of Spring Framework?

answer.Lightweight: Spring is lightweight if it comes to size and clarity. The essential version of spring framework is about 2MB.

Inversion of control: Loose coupling is accomplished in Spring, with the Inversion of Control system. The objects give their dominions rather than building or looking for dependent objects.

Aspect-oriented: Spring supports Aspect oriented programming and classifies application transaction logic from system services.

Container: Spring includes and controls the life sequence and configuration of application objects.

MVC Framework: Spring’s web structure is a well-designed web MVC structure, that presents a vast choice to web structures.

Business Management: Spring presents a logical transaction management interface that can scale down to a local transaction and scale up to global transactions.

Exception Handling: Spring presents a suitable API to transpose technology-specific differences (thrown by JDBC, Hibernate, or JDO) into constant, unchecked differences.

What are the Spring framework modules?

answer.The essential modules of the Spring framework are:

Core module

Context module

Bean module

Expression Language module

ORM module

JDBC module

OXM module

Java Messaging Service(JMS) module

Web-Portlet module

Transaction module

Web-Servlet module

Web module

Web-Struts module

Explain the Core Container (Application context) module

answer.This is the central Spring module, that implements the fundamental functionality of the Spring framework. BeanFactory is the core of any spring application. Spring framework was developed on the top of this module, that presents the Spring container.

BeanFactory – BeanFactory implementation model

answer.A BeanFactory is an implementation of the factory pattern that utilizes Inversion of Control to divide the application’s configuration and dependencies from the real application code.

The most regularly used BeanFactory implementation is the XmlBeanFactory class.

XMLBeanFactory

answer.The most beneficial one is

org.beans.springframework.factory.xml.XmlBeanFactory, that loads its beans based on the descriptions included in an XML file. This package translates the configuration metadata from an XML file and applies it to form a completely configured system or application.

Explain the AOP module

The AOP module is utilized for developing features for our Spring-enabled application. Much of the assistance has been granted by the AOP Alliance to assure the interoperability among Spring and other AOP frameworks. This module also includes metadata programming to Spring.

Describe the JDBC abstraction and DAO module

answer.With the JDBC abstraction and DAO module, we can be certain that we keep up the database code pure and easy, and stop problems that result from a crash to close database sources. It presents a layer of essential exceptions on top of the failure messages provided by several database servers. It also offers use of Spring’s AOP module to present transaction administration services for objects in a Spring application.

Describe the object/relational mapping integration module

answer.Spring also supports for the (ORM) engine over through JDBC by implementing the ORM module. Spring tools support to tie into several important ORM frameworks, including JDO, Hibernate and iBATIS SQL Maps. Spring’s transaction control supports all of these ORM frameworks like JDBC.

Describe the web module

answer.The Spring web module is created on the application context module, presenting a context that is suitable for web-based applications. This module also includes support for various web-oriented responsibilities such as transparently managing multipart requests for folder uploads and programmatic binding of application parameters to your business objects. It additionally includes integration support with Jakarta Struts.

what is the Spring MVC module

answer.MVC framework is presented by Spring for developing web applications. Spring can quickly be integrated with another MVC frameworks, but Spring’s MVC framework is a better choice as it uses IoC to provide for a total separation of controller logic from business objects. With Spring MVC you can declaratively bind request parameters to your business objects.

Spring configuration file

answer.Spring configuration folder is an XML file. This folder includes the sources information and explains how these sources are configured and presented to each other.

What is Spring IoC container?

answer.The Spring IoC is efficient for creating the objects, controlling them (with dependency injection (DI)), wiring them mutually, configuring them, as also controlling their complete lifecycle.

What are the advantages of IOC?

answer.IOC or dependency injection reduces the number of code in an application. It creates simple to test applications because no singletons or JNDI lookup mechanisms are needed in unit inspections. Loose coupling is supported with minimum work and least intrusive mechanism. IOC containers maintain eager instantiation and dull loading of services.

What are the common implementations of the ApplicationContext?

answer.The FileSystemXmlApplicationContext container stores the descriptions of the beans from an XML folder. The entire path of the XML bean configuration file should be presented to the constructor.

The ClassPathXmlApplicationContext container additionally loads the descriptions of the beans from an XML file. Here, you must set CLASSPATH correctly because this container will seem bean configuration XML folder in CLASSPATH.

The WebXmlApplicationContext: container loads the XML file with descriptions of all beans from inside a web application.