diff --git a/build-plugin/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/BootArchiveSupport.java b/build-plugin/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/BootArchiveSupport.java
index 12b68384e91f..647b36181bbf 100644
--- a/build-plugin/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/BootArchiveSupport.java
+++ b/build-plugin/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/BootArchiveSupport.java
@@ -147,7 +147,7 @@ CopyAction createCopyAction(Jar jar, ResolvedDependencies resolvedDependencies,
 	}
 
 	private @Nullable Integer asUnixNumeric(Property<ConfigurableFilePermissions> permissions) {
-		return permissions.isPresent() ? permissions.get().toUnixNumeric() : null;
+		return permissions.map(ConfigurableFilePermissions::toUnixNumeric).getOrNull();
 	}
 
 	private @Nullable Integer getDirMode(CopySpec copySpec) {
diff --git a/module/spring-boot-mustache/src/main/java/org/springframework/boot/mustache/autoconfigure/MustacheResourceTemplateLoader.java b/module/spring-boot-mustache/src/main/java/org/springframework/boot/mustache/autoconfigure/MustacheResourceTemplateLoader.java
index b388ff0b33c3..9767d5b00093 100644
--- a/module/spring-boot-mustache/src/main/java/org/springframework/boot/mustache/autoconfigure/MustacheResourceTemplateLoader.java
+++ b/module/spring-boot-mustache/src/main/java/org/springframework/boot/mustache/autoconfigure/MustacheResourceTemplateLoader.java
@@ -18,6 +18,8 @@
 
 import java.io.InputStreamReader;
 import java.io.Reader;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 
 import com.samskivert.mustache.Mustache;
 import com.samskivert.mustache.Mustache.Compiler;
@@ -45,7 +47,7 @@ public class MustacheResourceTemplateLoader implements TemplateLoader, ResourceL
 
 	private String suffix = "";
 
-	private String charSet = "UTF-8";
+	private Charset charSet = StandardCharsets.UTF_8;
 
 	private ResourceLoader resourceLoader = new DefaultResourceLoader(null);
 
@@ -61,7 +63,7 @@ public MustacheResourceTemplateLoader(String prefix, String suffix) {
 	 * Set the charset.
 	 * @param charSet the charset
 	 */
-	public void setCharset(String charSet) {
+	public void setCharset(Charset charSet) {
 		this.charSet = charSet;
 	}