Refine GraalVM tracing agent detection

This commit refines how GraalVM tracing agent detection works
for both test and application executions.

It rolls back the introduction of TestAotDetector done in 111309605c
and instead updates AotDetector.useGeneratedArtifacts()
to only detect "buildtime" and "runtime" imagecode system
property values by leveraging a new method
NativeDetector.inNativeImage(NativeDetector.Context...).

This commit also adds a workaround for
https://github.com/oracle/graal/issues/6691.

Closes gh-30511

spring-core/src/main/java/org/springframework/aot/AotDetector.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,11 +19,14 @@ package org.springframework.aot;
 import org.springframework.core.NativeDetector;
 import org.springframework.core.SpringProperties;
 
+import static org.springframework.core.NativeDetector.Context;
+
 /**
  * Utility for determining if AOT-processed optimizations must be used rather
  * than the regular runtime. Strictly for internal use within the framework.
  *
  * @author Stephane Nicoll
+ * @author Sebastien Deleuze
  * @since 6.0
  */
 public abstract class AotDetector {
@@ -36,6 +39,8 @@ public abstract class AotDetector {
 	 */
 	public static final String AOT_ENABLED = "spring.aot.enabled";
 
+	private static final boolean inNativeImage = NativeDetector.inNativeImage(Context.RUNTIME, Context.BUILD_TIME);
+
 	/**
 	 * Determine whether AOT optimizations must be considered at runtime. This
 	 * is mandatory in a native image but can be triggered on the JVM using
@@ -43,7 +48,7 @@ public abstract class AotDetector {
 	 * @return whether AOT optimizations must be considered
 	 */
 	public static boolean useGeneratedArtifacts() {
-		return (NativeDetector.inNativeImage() || SpringProperties.getFlag(AOT_ENABLED));
+		return (inNativeImage || SpringProperties.getFlag(AOT_ENABLED));
 	}
 
 }

spring-core/src/main/java/org/springframework/aot/nativex/feature/PreComputeFieldFeature.java

@@ -33,8 +33,9 @@ import org.graalvm.nativeimage.hosted.Feature;
 class PreComputeFieldFeature implements Feature {
 
 	private static Pattern[] patterns = {
-			Pattern.compile(Pattern.quote("org.springframework.core.NativeDetector#imageCode")),
-			Pattern.compile(Pattern.quote("org.springframework.cglib.core.AbstractClassGenerator#imageCode")),
+			Pattern.compile(Pattern.quote("org.springframework.core.NativeDetector#inNativeImage")),
+			Pattern.compile(Pattern.quote("org.springframework.cglib.core.AbstractClassGenerator#inNativeImage")),
+			Pattern.compile(Pattern.quote("org.springframework.aot.AotDetector#inNativeImage")),
 			Pattern.compile(Pattern.quote("org.springframework.") + ".*#.*Present"),
 			Pattern.compile(Pattern.quote("org.springframework.") + ".*#.*PRESENT"),
 			Pattern.compile(Pattern.quote("reactor.") + ".*#.*Available"),

spring-core/src/main/java/org/springframework/cglib/core/AbstractClassGenerator.java

@@ -43,8 +43,12 @@ abstract public class AbstractClassGenerator<T> implements ClassGenerator {
 	private static final boolean DEFAULT_USE_CACHE =
 			Boolean.parseBoolean(System.getProperty("cglib.useCache", "true"));
 
-	// See https://github.com/oracle/graal/blob/master/sdk/src/org.graalvm.nativeimage/src/org/graalvm/nativeimage/ImageInfo.java
-	private static final boolean imageCode = (System.getProperty("org.graalvm.nativeimage.imagecode") != null);
+	private static final boolean inNativeImage;
+
+	static {
+		String imageCode = System.getProperty("org.graalvm.nativeimage.imagecode");
+		inNativeImage = "buildtime".equals(imageCode) || "runtime".equals(imageCode);
+	}
 
 
 	private GeneratorStrategy strategy = DefaultGeneratorStrategy.INSTANCE;
@@ -354,7 +358,7 @@ abstract public class AbstractClassGenerator<T> implements ClassGenerator {
 				}
 			}
 			// SPRING PATCH BEGIN
-			if (imageCode) {
+			if (inNativeImage) {
 				throw new UnsupportedOperationException("CGLIB runtime enhancement not supported on native image. " +
 						"Make sure to include a pre-generated class on the classpath instead: " + getClassName());
 			}

spring-core/src/main/java/org/springframework/core/NativeDetector.java

@@ -16,6 +16,8 @@
 
 package org.springframework.core;
 
+import org.springframework.lang.Nullable;
+
 /**
  * A common delegate for detecting a GraalVM native image environment.
  *
@@ -25,12 +27,61 @@ package org.springframework.core;
 public abstract class NativeDetector {
 
 	// See https://github.com/oracle/graal/blob/master/sdk/src/org.graalvm.nativeimage/src/org/graalvm/nativeimage/ImageInfo.java
-	private static final boolean imageCode = (System.getProperty("org.graalvm.nativeimage.imagecode") != null);
+	@Nullable
+	private static final String imageCode = System.getProperty("org.graalvm.nativeimage.imagecode");
+
+	private static final boolean inNativeImage = (imageCode != null);
 
 	/**
-	 * Returns {@code true} if invoked in the context of image building or during image runtime, else {@code false}.
+	 * Returns {@code true} if running in a native image context (for example {@code buildtime}, {@code runtime} or
+	 * {@code agent}) expressed by setting {@code org.graalvm.nativeimage.imagecode} system property to any value, else {@code false}.
 	 */
 	public static boolean inNativeImage() {
-		return imageCode;
+		return inNativeImage;
 	}
+
+	/**
+	 * Returns {@code true} if running in any of the specified native image context(s), else {@code false}.
+	 * @param contexts the native image context(s)
+	 * @since 6.0.10
+	 */
+	public static boolean inNativeImage(Context... contexts) {
+		for (Context context: contexts) {
+			if (context.key.equals(imageCode)) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	/**
+	 * Native image context as defined in
+	 * <a href="https://github.com/oracle/graal/blob/master/sdk/src/org.graalvm.nativeimage/src/org/graalvm/nativeimage/ImageInfo.java">ImageInfo.java</a>.
+	 *
+	 * @since 6.0.10
+	 */
+	public enum Context {
+
+		/**
+		 * The code is executing in the context of image building.
+		 */
+		BUILD_TIME("buildtime"),
+
+		/**
+		 * The code is executing at image runtime.
+		 */
+		RUNTIME("runtime");
+
+		private final String key;
+
+		Context(final String key) {
+			this.key = key;
+		}
+
+		@Override
+		public String toString() {
+			return this.key;
+		}
+	}
+
 }