Describe your experience with caching in projects and how it affects system performance.

Caching in projects was used to reduce response time and decrease the load on the database or external services. For example, in a Java application, caching was implemented using the Ehcache library or Spring Cache built-in.

Cache allows storing frequently requested data in memory, which speeds up access to it and reduces the number of repeated calculations or requests. This is especially useful for data that rarely changes.

Example of using Spring Cache:

@Service
public class ProductService {

    @Cacheable("products")
    public Product getProductById(Long id) {
        // Long database query
        return productRepository.findById(id).orElse(null);
    }
}

In this example, the first call will load the product from the database, and subsequent calls will retrieve data from the cache, significantly improving system performance.