Use context class loader when watching SSL resource

Update `BundleContentProperty` to use a provided resource loader when
watching files.

Fixes gh-42468

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/ssl/BundleContentProperty.java

@@ -18,9 +18,9 @@
 
 import java.nio.file.Path;
 
-import org.springframework.boot.io.ApplicationResourceLoader;
 import org.springframework.boot.ssl.pem.PemContent;
 import org.springframework.core.io.Resource;
+import org.springframework.core.io.ResourceLoader;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
@@ -51,9 +51,10 @@ boolean hasValue() {
 		return StringUtils.hasText(this.value);
 	}
 
-	Path toWatchPath() {
+	Path toWatchPath(ResourceLoader resourceLoader) {
 		try {
-			Resource resource = getResource();
+			Assert.state(!isPemContent(), "Value contains PEM content");
+			Resource resource = resourceLoader.getResource(this.value);
 			if (!resource.isFile()) {
 				throw new BundleContentNotWatchableException(this);
 			}
@@ -68,9 +69,4 @@ Path toWatchPath() {
 		}
 	}
 
-	private Resource getResource() {
-		Assert.state(!isPemContent(), "Value contains PEM content");
-		return new ApplicationResourceLoader().getResource(this.value);
-	}
-
 }

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/ssl/SslPropertiesBundleRegistrar.java

@@ -111,7 +111,7 @@ private Set<Path> watchedPaths(String bundleName, List<BundleContentProperty> pr
 		try {
 			return properties.stream()
 				.filter(BundleContentProperty::hasValue)
-				.map(BundleContentProperty::toWatchPath)
+				.map((content) -> content.toWatchPath(this.resourceLoader))
 				.collect(Collectors.toSet());
 		}
 		catch (BundleContentNotWatchableException ex) {

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/ssl/BundleContentPropertyTests.java

@@ -22,9 +22,15 @@
 
 import org.junit.jupiter.api.Test;
 
+import org.springframework.boot.io.ApplicationResourceLoader;
+import org.springframework.core.io.ResourceLoader;
+
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
+import static org.mockito.BDDMockito.then;
+import static org.mockito.Mockito.atLeastOnce;
+import static org.mockito.Mockito.spy;
 
 /**
  * Tests for {@link BundleContentProperty}.
@@ -72,7 +78,7 @@ void hasValueWhenHasEmptyValueReturnsFalse() {
 	@Test
 	void toWatchPathWhenNotPathThrowsException() {
 		BundleContentProperty property = new BundleContentProperty("name", PEM_TEXT);
-		assertThatIllegalStateException().isThrownBy(property::toWatchPath)
+		assertThatIllegalStateException().isThrownBy(() -> property.toWatchPath(new ApplicationResourceLoader()))
 			.withMessage("Unable to convert value of property 'name' to a path");
 	}
 
@@ -81,13 +87,24 @@ void toWatchPathWhenPathReturnsPath() throws URISyntaxException {
 		URL resource = getClass().getResource("keystore.jks");
 		Path file = Path.of(resource.toURI()).toAbsolutePath();
 		BundleContentProperty property = new BundleContentProperty("name", file.toString());
-		assertThat(property.toWatchPath()).isEqualTo(file);
+		assertThat(property.toWatchPath(new ApplicationResourceLoader())).isEqualTo(file);
+	}
+
+	@Test
+	void toWatchPathUsesResourceLoader() throws URISyntaxException {
+		URL resource = getClass().getResource("keystore.jks");
+		Path file = Path.of(resource.toURI()).toAbsolutePath();
+		BundleContentProperty property = new BundleContentProperty("name", file.toString());
+		ResourceLoader resourceLoader = spy(new ApplicationResourceLoader());
+		assertThat(property.toWatchPath(resourceLoader)).isEqualTo(file);
+		then(resourceLoader).should(atLeastOnce()).getResource(file.toString());
 	}
 
 	@Test
 	void shouldThrowBundleContentNotWatchableExceptionIfContentIsNotWatchable() {
 		BundleContentProperty property = new BundleContentProperty("name", "https://example.com/");
-		assertThatExceptionOfType(BundleContentNotWatchableException.class).isThrownBy(property::toWatchPath)
+		assertThatExceptionOfType(BundleContentNotWatchableException.class)
+			.isThrownBy(() -> property.toWatchPath(new ApplicationResourceLoader()))
 			.withMessageContaining("Only 'file:' resources are watchable");
 	}