Three new article modules: configuration binding, profiles and config data, Spring AOP

configuration-properties/  @ConfigurationProperties vs @Value on Spring Boot 4.1.1.
  The relaxed-binding matrix is generated by binding each spelling rather than
  transcribed, and re-checked against real processes -- the in-process probe was
  wrong twice before it was right. Records the three findings that came out of it:
  @Value does get relaxed resolution inside Spring Boot (Boot attaches
  ConfigurationPropertySources), the configuration processor silently stops
  generating metadata on JDK 23+ when declared as a plain dependency, and @Valid is
  not what makes nested constraints run.

profiles-and-config/       Precedence, profiles, spring.config.import and config trees.
  /precedence reports every source holding a property in rank order with file and
  line, which turns "my profile file had no effect" into a two-line answer. Also
  pins the counterintuitive one: an imported file outranks the file that imported it.

spring-aop/                Designators, proxy types, and aspects that do not fire.
  One advice per supported designator so the reference table is generated from real
  matches; all fourteen unsupported designators fed to the parser. Two corrections to
  the reference documentation: unsupported designators throw
  UnsupportedPointcutPrimitiveException (extends RuntimeException, not
  IllegalArgumentException), and spring-boot-starter-aop was renamed to
  spring-boot-starter-aspectj in Boot 4.

19 contract tests across the three modules, 15 captured transcripts, all regenerated
by scripts/run-all.sh. Verified on Spring Boot 4.1.1, Spring Framework 7.0.9,
JDK 25.0.4.1.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Gip4srpzMwjgoba6uEfbr5

spring-aop/docs/06-diagnosing-a-silent-aspect.md

@@ -0,0 +1,75 @@
+[← Broken aspect gallery](05-broken-aspect-gallery.md) · [Index](../README.md)
+
+# 6. Diagnosing a silent aspect
+
+Endpoint: [`AopDiagnosticsEndpoint`](../src/main/java/com/ankurm/aop/web/AopDiagnosticsEndpoint.java).
+
+Almost every non-firing aspect is one of three things, and all three are visible in one place.
+
+## The three questions, in order
+
+**1. Is the bean proxied at all?**
+
+```java
+AopUtils.isAopProxy(bean)
+```
+
+`false` means no pointcut matched this bean, or it is not a bean. Stop here and check the
+pointcut and the registration.
+
+**2. Which kind of proxy?**
+
+```java
+AopUtils.isJdkDynamicProxy(bean)   // interfaces only
+AopUtils.isCglibProxy(bean)        // subclass
+```
+
+If it is a JDK proxy and your method is not on an interface, that is your answer.
+
+**3. Is your advice in the advisor list?**
+
+```java
+if (bean instanceof Advised advised) {
+    Arrays.stream(advised.getAdvisors())
+          .map(a -> a.getAdvice().getClass().getSimpleName())
+          .forEach(System.out::println);
+}
+```
+
+Proxied, right kind, and your advice missing means the pointcut matched the *bean* but not the
+*method*.
+
+## Output
+
+```
+  defaultOrderService    CGLIB subclass     target=DefaultOrderService
+      class      : DefaultOrderService$$SpringCGLIB$$0
+      interfaces : (none)
+      advisors   : 11
+```
+
+## Testing a pointcut without an application
+
+The fastest check of all, and it belongs in a test rather than in a diagnostic endpoint:
+
+```java
+AspectJExpressionPointcut pointcut = new AspectJExpressionPointcut();
+pointcut.setExpression("execution(* com.example.service.*.*(..))");
+assertThat(pointcut.matches(Foo.class.getMethod("bar"), Foo.class)).isTrue();
+```
+
+Remember that `setExpression` does not parse; the parse happens on first `matches`. So this is
+also how you find out that a designator is unsupported before production does.
+
+## Logging
+
+```
+logging.level.org.springframework.aop=DEBUG
+```
+
+reports proxy creation per bean. Verbose, but it answers question 1 for every bean at once.
+
+## Delete the endpoint before shipping
+
+It reports internal wiring. If you want it permanently, put it behind the management port and
+authentication.