Fix for Sonar

Author: ComputerDaddyGuy

README.md

@@ -3,6 +3,7 @@
 [![Quality Gate Status](https://sonarcloud.io/api/project_badges/measure?project=ComputerDaddyGuy_JFileTreePrettyPrinter&metric=alert_status&token=42442b67d269c6a17b4578ba2d87731c92b8922a)](https://sonarcloud.io/summary/new_code?id=ComputerDaddyGuy_JFileTreePrettyPrinter)
 [![Security Rating](https://sonarcloud.io/api/project_badges/measure?project=ComputerDaddyGuy_JFileTreePrettyPrinter&metric=security_rating&token=42442b67d269c6a17b4578ba2d87731c92b8922a)](https://sonarcloud.io/summary/new_code?id=ComputerDaddyGuy_JFileTreePrettyPrinter)
 [![Vulnerabilities](https://sonarcloud.io/api/project_badges/measure?project=ComputerDaddyGuy_JFileTreePrettyPrinter&metric=vulnerabilities&token=42442b67d269c6a17b4578ba2d87731c92b8922a)](https://sonarcloud.io/summary/new_code?id=ComputerDaddyGuy_JFileTreePrettyPrinter)
+[![Coverage](https://sonarcloud.io/api/project_badges/measure?project=ComputerDaddyGuy_JFileTreePrettyPrinter&metric=coverage&token=42442b67d269c6a17b4578ba2d87731c92b8922a)](https://sonarcloud.io/summary/new_code?id=ComputerDaddyGuy_JFileTreePrettyPrinter)
 
 [![Maven Central](https://img.shields.io/maven-central/v/io.github.computerdaddyguy/jfiletreeprettyprinter.svg?color=blue)](https://maven-badges.herokuapp.com/maven-central/io.github.computerdaddyguy/jfiletreeprettyprinter/)
 [![Javadoc](https://javadoc.io/badge2/io.github.computerdaddyguy/jfiletreeprettyprinter/javadoc.svg?color=blue)](https://javadoc.io/doc/io.github.computerdaddyguy/jfiletreeprettyprinter)

src/main/java/io/github/computerdaddyguy/jfiletreeprettyprinter/PathPredicateBuilder.java

@@ -27,6 +27,7 @@
 @NullMarked
 public class PathPredicateBuilder {
 
+	@Nullable
 	private Predicate<Path> combinedPredicate;
 
 	/**

src/main/java/io/github/computerdaddyguy/jfiletreeprettyprinter/PathPredicates.java

@@ -106,7 +106,7 @@ public static Predicate<Path> hasExtension(String extension) {
 	 * @return a predicate testing for files to represent a directory
 	 */
 	public static Predicate<Path> isDirectory() {
-		return path -> PathUtils.isDirectory(path);
+		return PathUtils::isDirectory;
 	}
 
 	/**
@@ -115,7 +115,7 @@ public static Predicate<Path> isDirectory() {
 	 * @return a predicate testing for files to represent a file
 	 */
 	public static Predicate<Path> isFile() {
-		return path -> PathUtils.isFile(path);
+		return PathUtils::isFile;
 	}
 
 }

src/main/java/io/github/computerdaddyguy/jfiletreeprettyprinter/renderer/file/DefaultEmojiMapping.java

@@ -41,6 +41,7 @@ public DefaultEmojiMapping(
 		return emoji;
 	}
 
+	@Nullable
 	private final String extractExtension(String fileName) {
 		var dotIndex = fileName.lastIndexOf('.');
 		return dotIndex < 0 ? null : fileName.substring(dotIndex + 1);

src/main/java/io/github/computerdaddyguy/jfiletreeprettyprinter/renderer/file/EmojiFileFormatter.java

@@ -8,6 +8,7 @@
 import java.util.List;
 import java.util.Objects;
 import org.jspecify.annotations.NullMarked;
+import org.jspecify.annotations.Nullable;
 
 @NullMarked
 class EmojiFileFormatter implements FileFormatter {
@@ -25,7 +26,7 @@ private String getFileEmojiPrefix(Path p) {
 		return getEmojiPrefix(emoji);
 	}
 
-	private String getEmojiPrefix(String emoji) {
+	private String getEmojiPrefix(@Nullable String emoji) {
 		if (emoji == null) {
 			return "";
 		}

src/main/java/io/github/computerdaddyguy/jfiletreeprettyprinter/scanner/DefaultPathToTreeScanner.java

@@ -53,7 +53,7 @@ private TreeEntry handleDirectory(int depth, Path dir, @Nullable Predicate<Path>
 
 		try (var childrenStream = Files.newDirectoryStream(dir)) {
 			var it = directoryStreamToIterator(childrenStream, filter);
-			childEntries = handleDirectoryChildren(depth, dir, filter, it);
+			childEntries = handleDirectoryChildren(depth, dir, it, filter);
 		} catch (IOException e) {
 			throw new UncheckedIOException("Unable to list files for directory: " + dir, e);
 		}
@@ -66,7 +66,7 @@ private TreeEntry handleDirectory(int depth, Path dir, @Nullable Predicate<Path>
 		return new DirectoryEntry(dir, childEntries);
 	}
 
-	private List<TreeEntry> handleDirectoryChildren(int depth, Path dir, Predicate<Path> filter, Iterator<Path> pathIterator) {
+	private List<TreeEntry> handleDirectoryChildren(int depth, Path dir, Iterator<Path> pathIterator, @Nullable Predicate<Path> filter) {
 
 		var childEntries = new ArrayList<TreeEntry>();
 		int maxChildEntries = options.getChildLimit().applyAsInt(dir);