Troubleshooting Articles
3 articles about Troubleshooting. Explore Spring Boot implementation, design, and operations across related topics.
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Why @Transactional, @Cacheable, and @Async Don't Work in Spring Boot - Understanding AOP Proxies and Self-Invocation to Fix It
@Transactional doesn't roll back, @Cacheable hits the DB every time, @Async runs synchronously. All of these are caused by how Spring AOP proxies work. This article isolates five patterns - self-invocation, private/final methods, new, and missing enablement - with reproducible code and diagnostic steps, then compares workarounds such as extracting to a separate Bean, self-injection, and TransactionTemplate.
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How to Fix LazyInitializationException in Spring Boot + JPA - Causes and Solutions for "could not initialize proxy - no Session"
Solve the LazyInitializationException (could not initialize proxy - no Session) that crashes the moment you access a lazily-loaded association in Spring Data JPA, working backwards from how Hibernate sessions and transaction boundaries operate. Compares the four proper approaches—JOIN FETCH, @EntityGraph, DTO projection, and @Transactional—and provides criteria for making decisions without resorting to open-in-view=true or switching to EAGER.
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Spring Boot Application Won't Start? How to Isolate the Cause and Fix It
For anyone panicking at 'APPLICATION FAILED TO START'. Targeting Spring Boot 3.x, this guide walks through 7 typical patterns, including port conflicts, duplicate Beans, circular references, missing DataSource configuration, and profile mistakes, using a symptom-first reverse lookup. It also covers how to read FailureAnalyzer messages and how to use the --debug flag, with real examples.