Recognize the Patterns Behind Spring Annotations

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package com.example.infra;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.stereotype.Component;

@Component
public class AuditLoggingBeanPostProcessor implements BeanPostProcessor {

    private static final Logger log = LoggerFactory.getLogger(AuditLoggingBeanPostProcessor.class);

    @Override
    public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
        // Invoked BEFORE @PostConstruct or InitializingBean.afterPropertiesSet()
        return bean;
    }

    @Override
    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
        // Invoked AFTER bean is fully initialized. Ideal place to return dynamic proxy!
        if (bean.getClass().isAnnotationPresent(AuditMonitored.class)) {
            log.info("Registered audit monitoring proxy for bean: {}", beanName);
            // Return CGLIB or Dynamic Proxy wrapping bean
        }
        return bean;
    }
}

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package com.example.infra.aop;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class ExecutionTimeAspect {

    private static final Logger log = LoggerFactory.getLogger(ExecutionTimeAspect.class);

    @Around("@annotation(logExecutionTime)")
    public Object logTime(ProceedingJoinPoint joinPoint, LogExecutionTime logExecutionTime) throws Throwable {
        long start = System.currentTimeMillis();
        try {
            return joinPoint.proceed();
        } finally {
            long duration = System.currentTimeMillis() - start;
            if (duration > logExecutionTime.slowThresholdMs()) {
                log.warn("SLOW METHOD EXECUTION: {}.{}() took {}ms",
                    joinPoint.getSignature().getDeclaringTypeName(),
                    joinPoint.getSignature().getName(),
                    duration);
            }
        }
    }
}

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# 1. Run Spring Boot with condition evaluation report enabled
./mvnw spring-boot:run -Dspring-boot.run.arguments="--debug"

# 2. Inspect ConditionEvaluationReport in console output:
# ============================
# CONDITIONS EVALUATION REPORT
# ============================
# Positive matches:
# -----------------
# AuditLoggingAutoConfiguration matched:
#    - @ConditionalOnProperty (app.audit.enabled) found property 'true'
#
# Negative matches:
# -----------------
# RedisAuditStoreAutoConfiguration:
#    - Did not match: @ConditionalOnClass did not find org.springframework.data.redis.core.RedisTemplate