Introduction To Spring Framework Interview Questions and Answers
Spring Framework is one of the foremost wide used Java frameworks. Spring framework core ideas are “Dependency Injection” and “Aspect-Oriented Programming”.
Spring framework is often employed in traditional java applications additionally to attain loose coupling between completely different elements by implementing dependency injection and we will perform cross-cutting tasks like work and using spring support for aspect-oriented programming.
I like spring because it provides a couple of options and completely different modules for specific tasks like Spring MVC and Spring JDBC. Since it’s an open source framework with lots of online resources and active community members2hich makes it straightforward and fun at the same time.
Now, if you are looking for a job which is related to Spring Framework then you need to prepare for the 2019 Spring Framework Interview Questions. It is true that every interview is different as per the different job profiles but still to clear the interview you need to have a good and clear knowledge of Spring Framework. Here, we have prepared the important Spring Framework Interview Questions and answers which will help you get success in your interview.
Here’s a comprehensive list of 2019 Spring framework interview Questions and answers that are sometimes asked in an interview. This list of questions are divided into two parts which are as follows:
- Part 1 – Spring framework Interview Questions (Basic)
- Part 2 – Spring framework Interview Questions (Advanced)
Part 1 – Spring framework Interview Questions (Basic)
This first part covers the basic Spring framework Interview Questions and Answers
Q1.What are some of the important features and advantages of Spring Framework?
Spring Framework is constructed on a high of 2 style ideas – Dependency Injection and Aspect Oriented Programming.
Some of the benefits of using Spring Framework are:
- Reducing direct dependencies between completely different elements of the appliance, usually Spring IoC instrumentality is liable for initializing resources or beans and inject them as dependencies.
- Writing unit cases are straightforward in Spring framework as a result of our business logic doesn’t have direct dependencies with actual resource implementation categories. we are able to simply write a take a look at configuration and inject our mock beans for testing functions.
- Reduces the quantity of boiler-plate code, like initializing objects, open/close resources. I favor JdbcTemplate category heaps as a result of it helps us in removing all the boiler-plate code that comes with JDBC programming.
- Spring framework is split into many modules, it helps us to keep our application light-weight.
- Spring framework supports most of the Java EE options and even rather more. It’s continuously on high of the new technologies, as an example there’s a Spring project for Android to assist us to write higher code for native Android applications. This makes the spring framework an entire package and that we don’t have to be compelled to take care of a completely different framework for various necessities.
Q2.What do you understand by Dependency Injection?
Dependency Injection style pattern permits us to get rid of the hard-coded dependencies and create our application loosely coupled, extendible and reparable. we are able to implement dependency injection pattern to move the dependency resolution from compile-time to runtime.
Some of the advantages of using Dependency Injection are Separation of issues, Boilerplate Code reduction, Configurable elements, and straightforward unit testing.
Let us move to the next Spring framework Interview Questions.
Q3.What are the benefits of using Spring Tool Suite?
We can install plugins into Eclipse to use all the options of Spring Tool Suite. It comes with necessary stuff like adept support, Templates for making different kinds of Spring comes with higher performance with Spring applications.
I like STS as a result of it highlights the Spring elements and if you’re using AOP pointcuts and advice, then it clearly shows that ways can return below the precise pointcut. therefore instead of putting in everything on our own, I like using STS once developing Spring-based mostly applications.
Q4.Name some of the important Spring Modules?
This is the common Spring framework Interview Questions asked in an interview. Some of the necessary Spring Framework modules are:
- Spring Context – for dependency injection.
- Spring AOP – for Aspect Oriented Programming.
- Spring DAO – for information operations using DAO pattern
- Spring JDBC – for JDBC and DataSource support.
- Spring ORM – for ORM tools support like Hibernate
- Spring net Module – for making net applications.
- Spring MVC – Model-View-Controller implementation for making net applications, net services etc.
Q5.What is Aspect, Advice, Pointcut, JointPoint and Advice Arguments in AOP?
Aspect: Aspect is a category that implements cross-cutting issues, like group action management. Aspects are often a standard category organized then organized in Spring Bean configuration file or we are able to use Spring AspectJ support to declare a category as Aspect using @Aspect annotation.
Advice: recommendation is that the action was taken for a specific be a part of the purpose. In terms of programming, they’re ways that get dead once a particular be a part of purpose with matching pointcut is reached within the application.
Pointcut: Pointcut is regular expressions that are matched with be a part of points to work out whether or not a recommendation has to be dead or not. Pointcut uses completely different forms of expressions that are matched with the be a part of points. Spring framework uses the AspectJ pointcut expression language for crucial the be a part of points wherever recommendation ways are applied.
Join Point: A be a part of the purpose is that the specific purpose of the application like technique execution, exception handling, ever-changing object variable values etc. In Spring AOP a be a part of points is often the execution of a technique.
Advice Arguments: we are able to pass arguments within the recommendation ways. we are able to use args() expression within the pointcut to be applied to any technique that matches the argument pattern. If we tend to use this, then we want to use the constant name within the recommendation technique from wherever argument kind is set.
Part 2 – Spring framework Interview Questions (Advanced)
Let us now have a look at the advanced Spring framework Interview Questions.
Q6.What is the difference between Spring AOP and AspectJ AOP?
AspectJ is that the industry-standard implementation for Aspect Oriented Programming whereas Spring implements AOP for a few cases. Main variations between Spring AOP and AspectJ are:
- Spring AOP is easier to use than AspectJ as a result of we tend to don’t have to be compelled to worry concerning the weaving method.
- Spring AOP supports AspectJ annotations, therefore if you’re conversant in AspectJ then operating with Spring AOP is less complicated.
- Spring AOP supports solely proxy-based AOP, therefore it is often applied solely to technique execution be a part of points. AspectJ support all types of pointcuts.
- One of the defects of Spring AOP is that it is often applied solely to the beans created through Spring Context.
Q7.What is a Spring Bean?
Any traditional java category that’s initialized by Spring IoC is named Spring Bean. we tend to use Spring ApplicationContext to urge the Spring Bean instance.
Spring IoC manages the life cycle of Spring Bean, bean scopes and injecting any needed dependencies within the bean.
Let us move to the next Spring framework Interview Questions.
Q8). What are the different scopes of Spring Bean?
There are 5 scopes outlined for Spring Beans.
- singleton: only 1 instance of the bean is created for every instrumentality. this can be the default scope for the spring beans. whereas using this scope, ensure spring bean doesn’t have shared instance variables otherwise it’d cause information inconsistency problems as a result of it’s not thread-safe.
- prototype: a replacement instance are created on every occasion the bean is requested.
- request: this can be the same as the paradigm scope, but it’s meant to be used for net applications. a replacement instance of the bean is created for every HTTP request.
- session: a replacement bean is created for every HTTP session by the instrumentality.
- international-session: this can be accustomed to produce global session beans for Portlet applications.
Spring Framework is extendible and that we will produce our own scopes too, but most of the days we tend to are sensible with the scopes provided by the framework.
To set spring bean scopes we are able to use “scope” attribute in bean part or @Scope annotation for annotation based mostly configurations.
To set spring bean scopes we can use “scope” attribute in bean element or @Scope annotation for annotation based configurations.
Q9. What is the Spring Bean life cycle?
This is the frequently asked Spring framework Interview Questions in an interview. Spring Beans are initialized by Spring instrumentality and everyone the dependencies are injected. once a context is destroyed, it additionally destroys all the initialized beans. This works well in most of the cases however typically we would like to initialize alternative resources or do some validation before creating our beans able to use. Spring framework provides support for post-initialization and pre-destroy ways in spring beans.
We can do that by 2 ways that – by implementing InitializingBean and DisposableBean interfaces or using init-method and destroy-method attribute in spring bean configurations.
Q10. Does Spring Bean provide thread safety?
The default scope of Spring bean is a singleton, therefore there’ll be only 1 instance per context. which means that everyone the having a category level variable that any thread will update can cause inconsistent information. thus in default mode, spring beans don’t seem to be thread-safe.
However, we are able to modification spring bean scope to request, paradigm or session to attain thread-safety at the value of performance. It’s a design decision and supported the project necessities.
This has been a guide to List Of Spring Framework Interview Questions and Answers so that the candidate can crackdown these Spring Framework Interview Questions easily. Here in this post, we have studied top Spring Framework Interview Questions which are often asked in interviews. You may also look at the following articles to learn more –