@After and @AfterReturning in Spring Boot - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the @After annotation do in Spring AOP?

The @After annotation runs advice after a method finishes, no matter if it returns normally or throws an exception.

beginner

How is @AfterReturning different from @After in Spring AOP?

@AfterReturning runs advice only after a method completes successfully (returns without exception). It can access the returned value.

intermediate

Show a simple example of @AfterReturning advice that logs the returned value.

@AfterReturning(pointcut = "execution(* com.example.service.*.*(..))", returning = "result") public void logReturnValue(Object result) { System.out.println("Returned: " + result); }

intermediate

When would you use @After instead of @AfterReturning?

Use @After when you want to run code after a method finishes regardless of success or failure, like cleaning up resources.

advanced

Can @AfterReturning advice modify the returned value before it reaches the caller?

No, @AfterReturning can read the returned value but cannot change it. To modify return values, use @Around advice.

What happens if a method throws an exception? Which advice runs?

A @After advice runs, but @AfterReturning does not.

B Both @After and @AfterReturning run.

C Only @AfterReturning runs.

D Neither advice runs.

@After runs after method completion no matter what. @AfterReturning runs only if the method returns normally.

Which annotation lets you access the method's return value?

A @After

B @Before

C @AfterReturning

D @Around

@AfterReturning can capture the returned value using the 'returning' attribute.

If you want to run code after a method no matter what, which advice do you choose?

A @Around

B @AfterReturning

C @Before

D @After

@After advice runs after method execution regardless of outcome.

Can @AfterReturning advice change the method's return value?

A No, it can only read the value.

B Only if combined with @Before.

C Only if the method is void.

D Yes, always.

@AfterReturning advice can read but not modify the returned value.

Which advice type would you use to modify the return value?

A @After

B @Around

C @AfterReturning

D @Before

@Around advice can control and modify the method execution and its return value.

Explain the difference between @After and @AfterReturning in Spring AOP.

Think about what happens if the method throws an error.

Describe a real-life scenario where you would use @After advice instead of @AfterReturning.

Consider what happens if a method fails but you still want to do something.