Top 100+ Spring Aop Interview Questions And Answers
Question 1. What Is A Pointcut, A Join Point, An Advice, An Aspect, Weaving, Introduction, Target Object, Aop Proxy?
Answer :
Pointcut
An expression that selects one or greater Join Points
Join Point
A point in the execution of a program including a technique name or exception thrown
Advice
Code to be carried out at each decided on Join Point
Aspect
A module that encapsulates pointcuts and recommendation
Weaving
Technique by means of which factors are blended with main code
Introduction
Spring AOP allows to introduce new interfaces (and a corresponding application) to any item advises.
Target Object
An item is assisted with the aid of one or more respects. Also referred to as the object advised.
AOP Proxy
AOP proxy is an object used to perform the agreement vicinity. This object is created through the AOP framework. In Spring AOP proxy is part of JDK dynamic proxy or proxy CGLIB.
Question 2. How Does Spring Solve (enforce) A Cross Cutting Concern?
Answer :
Implement your mainline application logic:
Focusing on the center problem
Write components to implement your go-cutting issues
Spring presents many elements out-of-the-container Weave the factors into your application
Adding the pass-cutting behaviors to the proper places.
J2EE Interview Questions
Question 3. Which Are The Limitations Of The Two Proxy-types?
Answer :
Spring will create both JDK or CGLib proxies
JDK Proxy
Also known as dynamic proxies
API is built into the JDK
Requirements: Java interface(s)
All interfaces proxied
CGLib Proxy
NOT built into JDK
Included in Spring jars
Used when interface now not to be had
Cannot be applied to final instructions or approach
Question four. How Many Advice Types Does Spring Support. What Are They Used For?
Answer :
Before recommendation: Advice that executes earlier than a join factor, however which does now not have the capability to prevent execution go with the flow proceeding to the be part of factor (except it throws an exception).
After returning recommendation: Advice to be executed after a be a part of point completes usually: as an instance, if a technique returns with out throwing an exception.
After throwing recommendation: Advice to be executed if a technique exits by means of throwing an exception.
After advice: Advice to be carried out irrespective of the method by using which a be part of factor exits (regular or exquisite go back).
Around recommendation: Advice that surrounds a join factor together with a way invocation. This is the most powerful kind of recommendation. Around advice can carry out custom behavior earlier than and after the approach invocation. It is also chargeable for choosing whether to continue to the join factor or to shortcut the cautioned approach execution through returning its very own go back value or throwing an exception.
J2EE Tutorial
Question five. What Do You Have To Do To Enable The Detection Of The @component Annotation?
Answer :
To use @AspectJ elements in a Spring configuration you want to allow Spring support for configuring Spring AOP based totally on @AspectJ components, and autoproxying beans based on whether or not or now not they may be advised via those elements.
Enabling @AspectJ Support with Java configuration
To enable @AspectJ support with Java @Configuration add the @EnableAspectJAutoProxy annotation:
@Configuration
@EnableAspectJAutoProxy
public magnificence AppConfig
Enabling @AspectJ Support with XML configuration
To allow @AspectJ guide with XML based configuration use the <aop:aspectj-autoproxy/> element:
<aop:aspectj-autoproxy/>
Java-Springs Interview Questions
Question 6. Name Three Typical Cross Cutting Concerns?
Answer :
Logging
Security
Transaction
Question 7. What Does @enableaspectjautoproxy Do?
Answer :
To permit @AspectJ help with Java @Configuration upload the @EnableAspectJAutoProxy annotation:
@Configuration
@EnableAspectJAutoProxy
public class AppConfig
Java-Springs Tutorial Hibernate Interview Questions
Question 8. What Is A Named Pointcut?
Answer :
A named pointcut can be declared inner an <aop:config> detail, allowing the pointcut definition to be shared throughout several aspects and advisors.
<aop:config>
<aop:pointcut id="businessService" expression="execution(* com.Xyz.Myapp.Service.*.*(..))"/>
</aop:config>
Question 9. How Do You Externalize Pointcuts? What Is The Advantage Of Doing This?
Answer :
Externalize the pointcut to a named pointcut. Avoid to writing complex pointcut expression throughout the utility.
Core-Spring (based totally on Spring 3 . 2) Interview Questions
Question 10. What Is The Joinpoint Argument Used For?
Answer :
Context supplied by using the JoinPoint parameter and Context about the intercepted factor.
Hibernate Tutorial
Question eleven. What Is A Proceedingjoinpoint?
Answer :
An around advice is a unique advice that can manipulate when and if a way (or other join factor) is done. This is proper for round advices best, so that they require an issue of type ProceedingJoinPoint, while other advices simply use a simple JoinPoint. ProceedingJoinPoint is used as a controversy of the techniques which pointers for before, after, after throwing and round. ProceedingJoinPoint has the strategies like getKind, getTarget, continue etc.
MVC Framework Interview Questions
Question 12. What Are The Five Advice Types Called?
Answer :
Before
After
AfterThrowing
AfterReturning
Around
J2EE Interview Questions
Question 13. What Are The Limitations Of Spring Aop?
Answer :
Can only recommend non-private strategies
Can simplest apply elements to Spring Beans
Limitations of weaving with proxies
When the usage of proxies, assume technique a() calls method b() at the equal elegance/interface
recommendation will by no means be achieved for technique b()
MVC Framework Tutorial
Question 14. What Are The Supported Aspectj Pointcut Designators In Spring Aop?
Answer :
Execution
This
Target
Args
@target
@args
@inside
@annotation
Question 15. How To Declare Aspect In Spring Aop?
Answer :
In XML.
<bean class="com.Doj.Aop.LoggingAspect" id="loggingAspect">
<!-- configure properties of aspect here -->
</bean>
In Java
@Aspect
@Component
magnificence LoggingAspect
//recommendation
//pointcut
Framework7 Interview Questions
Question 16. How To Declare A Pointcut In Spring Aop?
Answer :
Find the below code snippet.
@Pointcut("execution(* save(..))")
personal void dataSave
Framework7 Tutorial
Question 17. What Do You Understand By Load-time Weaving (ltw) In Spring?
Answer :
Load-time weaving (LTW) or Run time weaving is a system of weaving AspectJ factors into the lessons of the application whilst the training are being loaded in JVM.
Maven Interview Questions
Question 18. What Is Aspect Oriented Programming (aop) In Spring?
Answer :
Aspect Oriented Programming works like Object Oriented Programming. In Object Oriented Programming, the unit of modularity is Object But in Aspect Oriented Programming the unit of modularity is Aspect. Aspect works as the modularization of worries called crosscutting worries in AOP. AOP framework is pluggable in spring. AOP offers declarative agency carrier and allows customers to put into effect custom aspects.
Java-Springs Interview Questions
Question 19. Define Aop Terminologies In Spring?
Answer :
Aspect: In a couple of lessons, the modularization of issues that acts as crosscutting issues.
Example :Transaction management
Join Point: Join Point is a factor at some point of the execution of the approach.
Advice: At a be a part of point, the motion taken by means of element is Advice.
Pointcut: Those predicates which matches join point is referred to as Pointcut.
Weaving: Other utility kind may be linked with element and that is referred to as weaving.
Introduction: Introduction is defining additional strategies fields for a type.
Target item: Those objects which can be cautioned by means of elements are Target Object.
AOP proxy: AOP framework creates an item to satisfy aspect settlement, that item is AOP proxy.
Maven Tutorial
Question 20. Define The Types Of Advice In Spring Aop.
Answer :
In Spring AOP, forms of recommendation are
Before: Advice that runs earlier than a join point.
After returning: Advice that runs after a be a part of factor normal completion.
After throwing: Advice which runs when a techniques exits by means of throwing an exception.
After: Advice that runs after the be a part of point exit with the aid of any way.
Around: Advice that runs surrounding to join factor. Example :approach invocation.
Java collections framework Interview Questions
Question 21. How To Enable @aspectj Support?
Answer :
Include the below XML code in application XML
<aop:aspectj-autoproxy/>
Question 22. When To Use Spring Aop And When To Use Full Aspectj?
Answer :
If we only want to recommendation the execution of operations on Spring beans then we ought to use Spring AOP. Spring AOP is simpler than AspectJ. Full AspectJ calls for the AspectJ complier within the build manner.
In case if we advice items now not to be managed through Spring Container, use AspectJ.
JUnit Tutorial
Question 23. What Are The Required Libraries To Run Aspectj Ltw In Spring?
Answer :
spring-aop.Jar
aspectjrt.Jar
aspectjweaver.Jar
JUnit Interview Questions
Question 24. What Is The Concept Of Aop? Which Problem Does It Solve?
Answer :
Aspect-Oriented Programming (AOP) is some other manner of element to some areas of utility i.E. Move cutting issue like security, logging and transaction. AOP is simple supplement of OOP programming for distinct worries. In OOP, the important thing unit of modularity is the magnificence, whereas in AOP the unit of modularity is the thing.
Aspect-Oriented Programming (AOP) allows modularization of move-reducing issues to solve following issues.
To keep away from tangling
To get rid of scattering.
Hibernate Interview Questions
