@CacheEvict for invalidation in Spring Boot - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to evict the cache named 'books' after the method runs.

Spring Boot

@CacheEvict(cacheNames = "[1]")
public void clearCache() {
    // method body
}

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

Ausers

Bproducts

Corders

Dbooks

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong cache name that does not exist.

Forgetting to specify the cache name.

The @CacheEvict annotation uses the cacheNames attribute to specify which cache to clear. Here, 'books' is the correct cache name to evict.

2fill in blank

medium

Complete the code to evict all entries in the 'books' cache after the method runs.

Spring Boot

@CacheEvict(cacheNames = "books", [1] = true)
public void clearAllBooksCache() {
    // method body
}

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

AallEntries

Bkey

Ccondition

DbeforeInvocation

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'key' instead of 'allEntries' to clear all cache entries.

Not setting the attribute to true.

The allEntries attribute set to true tells Spring to evict all entries in the specified cache.

3fill in blank

hard

Fix the error in the code to evict the cache entry with key '123' from the 'books' cache.

Spring Boot

@CacheEvict(cacheNames = "books", key = "[1]")
public void evictBook() {
    // method body
}

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

A123

B'123'

C"123"

Dkey

Attempts:

3 left

💡 Hint

Common Mistakes

Using a number without quotes as key.

Using double quotes inside double quotes without escaping.

The key attribute requires a SpEL expression as a string. The key '123' must be enclosed in single quotes inside the double quotes.

4fill in blank

hard

Fill both blanks to evict the cache entry with key 'id' before the method runs.

Spring Boot

@CacheEvict(cacheNames = "books", key = "[1]", [2] = true)
public void evictBefore(Long id) {
    // method body
}

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

A#id

Bfalse

CbeforeInvocation

Dtrue

Attempts:

3 left

💡 Hint

Common Mistakes

Using the parameter name without '#' in key.

Not setting beforeInvocation to true.

The key should be #id to refer to the method parameter. The beforeInvocation attribute set to true evicts the cache before the method runs.

5fill in blank

hard

Fill all three blanks to evict the cache entry with key 'user.id' only if the user's status is 'inactive'.

Spring Boot

@CacheEvict(cacheNames = "users", key = "[1]", condition = "[2] == 'inactive'", [3] = false)
public void evictInactiveUser(User user) {
    // method body
}

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

A#user.id

B#user.status

CbeforeInvocation

DallEntries

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong SpEL expressions for key or condition.

Confusing beforeInvocation with allEntries.

The key uses #user.id to access the user's id. The condition checks if #user.status equals 'inactive'. The beforeInvocation attribute set to false means eviction happens after method runs.