Made some elements private as needed in lib.

lib/src/main/java/com/diffplug/spotless/Formatter.java

@@ -30,14 +30,14 @@
 
 /** Formatter which performs the full formatting. */
 public final class Formatter {
-	final LineEnding.Policy lineEndingsPolicy;
-	final Charset encoding;
-	final Path rootDir;
-	final List<FormatterStep> steps;
+	private final LineEnding.Policy lineEndingsPolicy;
+	private final Charset encoding;
+	private final Path rootDir;
+	private final List<FormatterStep> steps;
 
 	private static final Logger logger = Logger.getLogger(Formatter.class.getName());
 
-	Formatter(LineEnding.Policy lineEndingsPolicy, Charset encoding, Path rootDirectory, List<FormatterStep> steps) {
+	private Formatter(LineEnding.Policy lineEndingsPolicy, Charset encoding, Path rootDirectory, List<FormatterStep> steps) {
 		this.lineEndingsPolicy = Objects.requireNonNull(lineEndingsPolicy, "lineEndingsPolicy");
 		this.encoding = Objects.requireNonNull(encoding, "encoding");
 		this.rootDir = Objects.requireNonNull(rootDirectory, "rootDir");

lib/src/main/java/com/diffplug/spotless/PaddedCell.java

@@ -78,7 +78,7 @@ public List<String> steps() {
 	 */
 	public static PaddedCell check(Formatter formatter, File file) {
 		byte[] rawBytes = ThrowingEx.get(() -> Files.readAllBytes(file.toPath()));
-		String raw = new String(rawBytes, formatter.encoding);
+		String raw = new String(rawBytes, formatter.getEncoding());
 		String original = LineEnding.toUnix(raw);
 		return check(formatter, file, original, MAX_CYCLE);
 	}

lib/src/main/java/com/diffplug/spotless/PaddedCellBulk.java

@@ -107,9 +107,9 @@ public static List<File> check(File rootDir, File diagnoseDir, Formatter formatt
 		// "fake" Formatter which can use the already-computed result of a PaddedCell as
 		FakeStep paddedCellStep = new FakeStep();
 		Formatter paddedFormatter = Formatter.builder()
-				.lineEndingsPolicy(formatter.lineEndingsPolicy)
-				.encoding(formatter.encoding)
-				.rootDir(formatter.rootDir)
+				.lineEndingsPolicy(formatter.getLineEndingsPolicy())
+				.encoding(formatter.getEncoding())
+				.rootDir(formatter.getRootDir())
 				.steps(Collections.singletonList(paddedCellStep))
 				.build();
 
@@ -132,7 +132,7 @@ public static List<File> check(File rootDir, File diagnoseDir, Formatter formatt
 					Path path = Paths.get(diagnoseFile + "." + padded.type().name().toLowerCase(Locale.ROOT) + i);
 					Files.createDirectories(path.getParent());
 					String version = padded.steps().get(i);
-					Files.write(path, version.getBytes(formatter.encoding));
+					Files.write(path, version.getBytes(formatter.getEncoding()));
 				}
 				// dump the type of the misbehavior to console
 				logger.finer("    " + relative + " " + padded.userMessage());
@@ -184,7 +184,7 @@ public String getName() {
 	/** Performs the typical spotlessApply, but with PaddedCell handling of misbehaving FormatterSteps. */
 	public static void apply(Formatter formatter, File file) throws IOException {
 		byte[] rawBytes = Files.readAllBytes(file.toPath());
-		String raw = new String(rawBytes, formatter.encoding);
+		String raw = new String(rawBytes, formatter.getEncoding());
 		String rawUnix = LineEnding.toUnix(raw);
 
 		// enforce the format
@@ -193,7 +193,7 @@ public static void apply(Formatter formatter, File file) throws IOException {
 		String formatted = formatter.applyLineEndings(formattedUnix, file);
 
 		// if F(input) == input, then the formatter is well-behaving and the input is clean
-		byte[] formattedBytes = formatted.getBytes(formatter.encoding);
+		byte[] formattedBytes = formatted.getBytes(formatter.getEncoding());
 		if (Arrays.equals(rawBytes, formattedBytes)) {
 			return;
 		}
@@ -208,15 +208,15 @@ public static void apply(Formatter formatter, File file) throws IOException {
 		// get the canonical bytes
 		String canonicalUnix = cell.canonical();
 		String canonical = formatter.applyLineEndings(canonicalUnix, file);
-		byte[] canonicalBytes = canonical.getBytes(formatter.encoding);
+		byte[] canonicalBytes = canonical.getBytes(formatter.getEncoding());
 		if (!Arrays.equals(rawBytes, canonicalBytes)) {
 			// and write them to disk if needed
 			Files.write(file.toPath(), canonicalBytes, StandardOpenOption.TRUNCATE_EXISTING);
 		}
 	}
 
 	/** Does whatever it takes to turn this path into an empty folder. */
-	static void cleanDir(Path folder) throws IOException {
+	private static void cleanDir(Path folder) throws IOException {
 		if (Files.exists(folder)) {
 			if (Files.isDirectory(folder)) {
 				Files.walkFileTree(folder, new SimpleFileVisitor<Path>() {

lib/src/main/java/com/diffplug/spotless/generic/EndWithNewlineStep.java

@@ -17,6 +17,7 @@
 
 import com.diffplug.spotless.FormatterStep;
 
+// TODO: Consider making this class (and every other class in lib & lib-extra) final
 public class EndWithNewlineStep {
 	/** Creates a FormatterStep which forces lines to end with a newline. */
 	public static FormatterStep create() {
@@ -25,7 +26,7 @@ public static FormatterStep create() {
 				unused -> EndWithNewlineStep::format);
 	}
 
-	static String format(String rawUnix) {
+	private static String format(String rawUnix) {
 		// simplifies the logic below if we can assume length > 0
 		if (rawUnix.isEmpty()) {
 			return "\n";