Why AOP matters in Spring Boot - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define an aspect in Spring Boot.

Spring Boot

@Aspect
@Component
public class LoggingAspect {
    @Before("[1]")
    public void logBefore() {
        System.out.println("Method is about to execute");
    }
}

Drag options to blanks, or click blank then click option'

A"execution(* com.example.service.*.*(..))"

B"@Aspect"

C"@Component"

D"@Before"

Attempts:

3 left

💡 Hint

Common Mistakes

Putting annotation names instead of pointcut expressions.

Leaving the blank empty.

Using incorrect pointcut syntax.

The @Before annotation needs a pointcut expression like execution(* com.example.service.*.*(..)) to specify where to apply the advice.

2fill in blank

medium

Complete the code to apply advice after a method returns successfully.

Spring Boot

@AfterReturning(pointcut = "execution(* com.example.repo.*.*(..))", returning = "result")
public void logAfterReturning([1] result) {
    System.out.println("Method returned: " + result);
}

Drag options to blanks, or click blank then click option'

AObject

Bvoid

CString

Dint

Attempts:

3 left

💡 Hint

Common Mistakes

Using void as parameter type.

Using a specific type that may not match the returned value.

The advice method parameter must match the type of the returned object or use Object to accept any type.

3fill in blank

hard

Fix the error in the advice method signature to correctly capture exceptions.

Spring Boot

@AfterThrowing(pointcut = "execution(* com.example.service.*.*(..))", throwing = "ex")
public void logAfterThrowing([1] ex) {
    System.out.println("Exception thrown: " + ex.getMessage());
}

Drag options to blanks, or click blank then click option'

AString

Bvoid

CException

Dint

Attempts:

3 left

💡 Hint

Common Mistakes

Using non-exception types as parameter.

Omitting the parameter.

The advice method must accept an Exception or subclass to capture thrown exceptions.

4fill in blank

hard

Fill both blanks to create a pointcut that matches all methods in service package and apply advice before execution.

Spring Boot

@Aspect
@Component
public class AuditAspect {
    @[1]("[2]")
    public void audit() {
        System.out.println("Audit: method called");
    }
}

Drag options to blanks, or click blank then click option'

ABefore

BAfter

Cexecution(* com.example.service.*.*(..))

Dexecution(* com.example.repo.*.*(..))

Attempts:

3 left

💡 Hint

Common Mistakes

Using @After instead of @Before.

Using pointcut for repo package instead of service.

The @Before annotation applies advice before method execution, and the pointcut expression matches all methods in the service package.

5fill in blank

hard

Fill all three blanks to create an around advice that logs method start, proceeds with method execution, and logs method end.

Spring Boot

@Around("[1]")
public Object logAround(ProceedingJoinPoint joinPoint) throws Throwable {
    System.out.println("Start: " + joinPoint.getSignature().getName());
    Object result = joinPoint.[2]();
    System.out.println("End: " + joinPoint.getSignature().getName());
    return [3];
}

Drag options to blanks, or click blank then click option'

Aexecution(* com.example.controller.*.*(..))

Bproceed

Cresult

Dexecution(* com.example.service.*.*(..))

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong pointcut expression.

Calling a wrong method instead of proceed().

Returning something other than the result.

The @Around advice uses a pointcut expression to match service methods, calls proceed() to continue execution, and returns the result.