From c565df96f5c6a7e8ca9a5aaeaf39f05b4ae611ae Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=A9bastien=20Deleuze?= <sdeleuze@vmware.com>
Date: Tue, 13 Jun 2023 14:25:32 +0200
Subject: [PATCH] Remove System.out calls in PreComputeFieldFeature

Closes gh-30571
---
 .../nativex/feature/PreComputeFieldFeature.java    | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/spring-core/src/main/java/org/springframework/aot/nativex/feature/PreComputeFieldFeature.java b/spring-core/src/main/java/org/springframework/aot/nativex/feature/PreComputeFieldFeature.java
index d548d6ff3d9..258a90785e1 100644
--- a/spring-core/src/main/java/org/springframework/aot/nativex/feature/PreComputeFieldFeature.java
+++ b/spring-core/src/main/java/org/springframework/aot/nativex/feature/PreComputeFieldFeature.java
@@ -26,12 +26,18 @@ import org.graalvm.nativeimage.hosted.Feature;
  * GraalVM {@link Feature} that substitutes boolean field values that match a certain pattern
  * with values pre-computed AOT without causing class build-time initialization.
  *
+ * <p>It is possible to pass <pre style="code">-Dspring.aot.precompute=verbose</pre> as a
+ * <pre style="code">native-image</pre> compiler build argument to display detailed logs
+ * about pre-computed fields.</p>
+ *
  * @author Sebastien Deleuze
  * @author Phillip Webb
  * @since 6.0
  */
 class PreComputeFieldFeature implements Feature {
 
+	private static final boolean verbose = "verbose".equals(System.getProperty("spring.aot.precompute"));
+
 	private static Pattern[] patterns = {
 			Pattern.compile(Pattern.quote("org.springframework.core.NativeDetector#inNativeImage")),
 			Pattern.compile(Pattern.quote("org.springframework.cglib.core.AbstractClassGenerator#inNativeImage")),
@@ -64,10 +70,14 @@ class PreComputeFieldFeature implements Feature {
 						try {
 							Object fieldValue = provideFieldValue(field);
 							access.registerFieldValueTransformer(field, (receiver, originalValue) -> fieldValue);
-							System.out.println("Field " + fieldIdentifier + " set to " + fieldValue + " at build time");
+							if (verbose) {
+								System.out.println("Field " + fieldIdentifier + " set to " + fieldValue + " at build time");
+							}
 						}
 						catch (Throwable ex) {
-							System.out.println("Field " + fieldIdentifier + " will be evaluated at runtime due to this error during build time evaluation: " + ex.getMessage());
+							if (verbose) {
+								System.out.println("Field " + fieldIdentifier + " will be evaluated at runtime due to this error during build time evaluation: " + ex.getMessage());
+							}
 						}
 					}
 				}