Fix Spring MethodParameters detection (#11647)

Fix Spring MethodParameters detection

Avoid throwing an exception if Spring is not found in loaded classes
Introduced an enum for reporting back result state and use UNKNOWN to
fallback to another detection method.

spotless

Co-authored-by: devflow.devflow-routing-intake <devflow.devflow-routing-intake@kubernetes.us1.ddbuild.io>

Author: jpbempel

dd-java-agent/agent-debugger/src/main/java/com/datadog/debugger/util/SpringHelper.java

@@ -10,17 +10,25 @@
 public class SpringHelper {
   private static final Logger LOGGER = LoggerFactory.getLogger(SpringHelper.class);
 
+  private enum DetectionResult {
+    UNKNOWN,
+    USE_METHOD_PARAMETERS,
+    USE_LOCAL_VARS
+  }
+
   public static boolean isSpringUsingOnlyMethodParameters(Instrumentation inst) {
-    try {
-      return isSpringUsingOnlyMethodParametersSpringVersion(inst);
-    } catch (Exception e) {
-      LOGGER.debug("isSpringUsingOnlyMethodParameters failed for SpringVersion", e);
+    DetectionResult detectionResult = isSpringUsingOnlyMethodParametersSpringVersion(inst);
+    if (detectionResult == DetectionResult.UNKNOWN) {
+      LOGGER.debug(
+          "isSpringUsingOnlyMethodParameters failed for SpringVersion, trying to detect specific class");
       // fallback to lookup for specific class
       return isSpringUsingOnlyMethodParametersSpecificClass(inst);
     }
+    return detectionResult == DetectionResult.USE_METHOD_PARAMETERS;
   }
 
-  private static boolean isSpringUsingOnlyMethodParametersSpringVersion(Instrumentation inst) {
+  private static DetectionResult isSpringUsingOnlyMethodParametersSpringVersion(
+      Instrumentation inst) {
     try {
       // scan for getting an already loaded class and get the classloader
       ClassLoader springClassLoader = null;
@@ -30,29 +38,41 @@ private static boolean isSpringUsingOnlyMethodParametersSpringVersion(Instrument
         }
       }
       if (springClassLoader == null) {
-        throw new IllegalStateException("Cannot find Spring classloader");
+        return DetectionResult.UNKNOWN;
       }
       Class<?> springVersionClass =
           Class.forName("org.springframework.core.SpringVersion", true, springClassLoader);
       Method m = springVersionClass.getDeclaredMethod("getVersion");
       String version = (String) m.invoke(null);
       ParsedSpringVersion springVersion = new ParsedSpringVersion(version);
       // if Spring version is 6.1+ only using MethodParameters
-      return springVersion.major > 6 || (springVersion.major == 6 && springVersion.minor >= 1);
-    } catch (Exception e) {
-      throw new RuntimeException(e);
+      return springVersion.major > 6 || (springVersion.major == 6 && springVersion.minor >= 1)
+          ? DetectionResult.USE_METHOD_PARAMETERS
+          : DetectionResult.USE_LOCAL_VARS;
+    } catch (Exception ex) {
+      LOGGER.debug("isSpringUsingOnlyMethodParametersSpringVersion failed", ex);
+      return DetectionResult.UNKNOWN;
     }
   }
 
   private static boolean isSpringUsingOnlyMethodParametersSpecificClass(Instrumentation inst) {
-    for (Class<?> clazz : inst.getAllLoadedClasses()) {
-      if ("org.springframework.web.client.RestClient".equals(clazz.getName())) {
-        // If this class (coming from Spring web since version 6.1) is found loaded it means Spring
-        // supports only getting parameter names from the MethodParameter attribute
-        return true;
+    try {
+      for (Class<?> clazz : inst.getAllLoadedClasses()) {
+        if (clazz == null) {
+          // class unloaded
+          continue;
+        }
+        if ("org.springframework.web.client.RestClient".equals(clazz.getName())) {
+          // If this class (coming from Spring web since version 6.1) is found loaded it means
+          // Spring
+          // supports only getting parameter names from the MethodParameter attribute
+          return true;
+        }
       }
+    } catch (Exception ex) {
+      LOGGER.debug("isSpringUsingOnlyMethodParametersSpecificClass failed: ", ex);
     }
-    // class not found, probably no Spring
+    // class not found, probably no Spring or failed
     return false;
   }