@Cacheable for read caching in Spring Boot - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the @Cacheable annotation do in Spring Boot?

The @Cacheable annotation tells Spring to save the result of a method call in a cache. When the method is called again with the same parameters, Spring returns the cached result instead of running the method again. This speeds up read operations.

beginner

How do you specify which cache to use with @Cacheable?

You use the value or cacheNames attribute inside @Cacheable to name the cache. For example, @Cacheable("books") tells Spring to use the cache named "books".

intermediate

What happens if the method parameters change when using @Cacheable?

Spring uses the method parameters as keys in the cache. If parameters change, Spring treats it as a new request and runs the method, then caches the new result separately.

intermediate

Can @Cacheable be used for write operations?

No, @Cacheable is meant for read caching only. For write or update operations, you use @CachePut or @CacheEvict to update or clear the cache.

beginner

What is a simple example of using @Cacheable in a Spring Boot service method?

  @Cacheable("items")
  public Item getItemById(Long id) {
    // Simulate slow database call
    return repository.findById(id).orElse(null);
  }

This caches the result of getItemById so repeated calls with the same id are faster.

What does @Cacheable do in Spring Boot?

A Disables caching for a method

B Deletes data from the database

C Updates the cache after a write operation

D Caches the result of a method to speed up repeated reads

@Cacheable caches method results to avoid repeated slow calls.

Which attribute specifies the cache name in @Cacheable?

A value or cacheNames

B key

C condition

D sync

The value or cacheNames attribute names the cache to use.

If method parameters change, what does Spring do with @Cacheable?

A Throws an error

B Returns the old cached result anyway

C Runs the method and caches the new result separately

D Clears the entire cache

Spring treats new parameters as a new cache key and caches the new result.

Which annotation should you use to update the cache after a write operation?

A @CachePut

B @Cacheable

C @CacheEvict

D @CacheDelete

@CachePut updates the cache after a method runs.

What is a benefit of using @Cacheable?

A Encrypts data in the cache

B Improves performance by avoiding repeated slow calls

C Automatically backs up the database

D Prevents method execution

Caching speeds up repeated method calls by returning stored results.

Explain how @Cacheable works in Spring Boot and why it is useful for read operations.

Think about how saving answers helps when you get the same question again.

Describe the difference between @Cacheable, @CachePut, and @CacheEvict in Spring Boot caching.

Consider reading, updating, and deleting cache entries.