David Kumar

Kubernetes orchestrates containerized applications at scale. Deployments manage ReplicaSets ensuring desired pod count. Services expose pods with stable endpoints. ConfigMaps externalize configuration. Secrets store sensitive data. Resource limits pre

Resilience4j provides resilience patterns for fault tolerance. Circuit breakers prevent cascading failures—open after threshold failures, allow retry after timeout. Rate limiters control request rates. Retry mechanisms handle transient failures. Bulkh

AOP separates cross-cutting concerns from business logic. Aspects modularize logging, security, transactions, caching. @Aspect defines aspect classes. @Before, @After, @Around specify advice timing. Pointcuts select join points using expressions. @Aro

Multi-tenancy serves multiple customers (tenants) from single application instance. Schema-per-tenant isolates data in separate databases. Shared schema with tenant ID column partitions data within tables. Discriminator-based approach uses JPA filters

Spring's event mechanism enables loose coupling between components. ApplicationEventPublisher publishes events. @EventListener handles events asynchronously or synchronously. Events extend ApplicationEvent or are POJOs. @TransactionalEventListener pub

Elasticsearch provides powerful full-text search capabilities. Spring Data Elasticsearch offers repository abstraction similar to JPA. @Document annotates entity classes with index mapping. @Field customizes field types and analyzers. Queries use meth