[openrewrite] RecipeNullabilityBestPractices

Author: Vincent Potucek

gradle/rewrite.gradle

@@ -2,9 +2,13 @@ apply plugin: 'org.openrewrite.rewrite'
 
 rewrite {
 	activeRecipe('com.diffplug.spotless.openrewrite.SanityCheck')
+	activeStyle('com.diffplug.spotless.openrewrite.SpotlessFormat')
 	exclusions.addAll(
 			'**.dirty.java',
+			'**DiffMessageFormatterTest.java',
+			'**EclipseJdtSortMembers.java',
 			'**FormatterProperties.java',
+			'**PaddedCellTaskTest.java',
 			'**_gradle_node_plugin_example_**',
 			'**gradle/changelog.gradle',
 			'**gradle/java-publish.gradle',

lib/src/compatDiktat1Dot2Dot5/java/com/diffplug/spotless/glue/diktat/compat/DiktatCompat1Dot2Dot5Adapter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2023-2024 DiffPlug
+ * Copyright 2023-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -53,7 +53,7 @@ static class FormatterCallback implements Function2<LintError, Boolean, Unit> {
 		}
 
 		@Override
-		public Unit invoke(LintError lintError, Boolean corrected) {
+		public @Nullable Unit invoke(LintError lintError, Boolean corrected) {
 			if (!corrected) {
 				errors.add(lintError);
 			}

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

@@ -120,12 +120,12 @@ private void verifyVersionRangesDoNotIntersect(NavigableMap<Integer, V> jvm2fmtV
 		}
 
 		/** @return Highest formatter version recommended for this JVM (null, if JVM not supported) */
-		@Nullable public V getRecommendedFormatterVersion() {
+		public @Nullable V getRecommendedFormatterVersion() {
 			Integer configuredJvmVersionOrNull = jvm2fmtMaxVersion.floorKey(Jvm.version());
 			return configuredJvmVersionOrNull == null ? null : jvm2fmtMaxVersion.get(configuredJvmVersionOrNull);
 		}
 
-		@Nullable public V getMinimumRequiredFormatterVersion() {
+		public @Nullable V getMinimumRequiredFormatterVersion() {
 			Integer configuredJvmVersionOrNull = jvm2fmtMinVersion.floorKey(Jvm.version());
 			return configuredJvmVersionOrNull == null ? null : jvm2fmtMinVersion.get(configuredJvmVersionOrNull);
 		}

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2024 DiffPlug
+ * Copyright 2016-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -105,12 +105,12 @@ private static PaddedCell check(Formatter formatter, File file, String original,
 		}
 		String appliedOnce = formatter.computeWithLint(original, file, exceptionPerStep);
 		if (appliedOnce.equals(original)) {
-			return Type.CONVERGE.create(file, Collections.singletonList(appliedOnce));
+			return Type.CONVERGE.create(file, List.of(appliedOnce));
 		}
 
 		String appliedTwice = formatter.computeWithLint(appliedOnce, file, exceptionPerStep);
 		if (appliedOnce.equals(appliedTwice)) {
-			return Type.CONVERGE.create(file, Collections.singletonList(appliedOnce));
+			return Type.CONVERGE.create(file, List.of(appliedOnce));
 		}
 
 		List<String> appliedN = new ArrayList<>();

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

@@ -61,7 +61,7 @@ class ValuePerStep<T> extends AbstractList<T> {
 	}
 
 	@Override
-	public T get(int index) {
+	public @Nullable T get(int index) {
 		if (multipleValues != null) {
 			return (T) multipleValues[index];
 		} else if (valueIdx == index) {

lib/src/main/java/com/diffplug/spotless/biome/BiomeStep.java

@@ -24,8 +24,8 @@
 import java.nio.file.Path;
 import java.nio.file.attribute.PosixFilePermission;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.HashSet;
+import java.util.Set;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -299,7 +299,7 @@ private State createState() throws IOException, InterruptedException {
 		validateBiomeExecutable(resolvedPathToExe);
 		validateBiomeConfigPath(configPath, version);
 		logger.debug("Using Biome executable located at  '{}'", resolvedPathToExe);
-		var exeSignature = FileSignature.signAsList(Collections.singleton(new File(resolvedPathToExe)));
+		var exeSignature = FileSignature.signAsList(Set.of(new File(resolvedPathToExe)));
 		makeExecutable(resolvedPathToExe);
 		return new State(resolvedPathToExe, exeSignature, configPath, language);
 	}

lib/src/main/java/com/diffplug/spotless/npm/EslintConfig.java

@@ -40,7 +40,7 @@ public EslintConfig withEslintConfigPath(@Nullable File eslintConfigPath) {
 		return new EslintConfig(eslintConfigPath, this.eslintConfigJs);
 	}
 
-	@Nullable public File getEslintConfigPath() {
+	public @Nullable File getEslintConfigPath() {
 		return eslintConfigPathSignature == null ? null : eslintConfigPathSignature.get().getOnlyFile();
 	}
 

lib/src/main/java/com/diffplug/spotless/npm/EslintFormatterStep.java

@@ -20,7 +20,6 @@
 import java.io.File;
 import java.io.IOException;
 import java.io.Serializable;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.Map;
@@ -65,7 +64,7 @@ public static Map<String, String> defaultDevDependencies() {
 	}
 
 	public static Map<String, String> defaultDevDependenciesWithEslint(String version) {
-		return Collections.singletonMap("eslint", version);
+		return Map.of("eslint", version);
 	}
 
 	public static FormatterStep create(Map<String, String> devDependencies, Provisioner provisioner, File projectDir, File buildDir, File cacheDir, NpmPathResolver npmPathResolver, EslintConfig eslintConfig) {

lib/src/main/java/com/diffplug/spotless/npm/EslintTypescriptConfig.java

@@ -39,7 +39,7 @@ public EslintConfig withEslintConfigPath(@Nullable File eslintConfigPath) {
 		return new EslintTypescriptConfig(eslintConfigPath, this.getEslintConfigJs(), getTypescriptConfigPath());
 	}
 
-	@Nullable public File getTypescriptConfigPath() {
+	public @Nullable File getTypescriptConfigPath() {
 		return typescriptConfigPathSignature == null ? null : this.typescriptConfigPathSignature.get().getOnlyFile();
 	}
 }

lib/src/main/java/com/diffplug/spotless/npm/JsonWriter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2023 DiffPlug
+ * Copyright 2016-2025 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,7 +21,6 @@
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
-import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.stream.Collectors;
@@ -45,7 +44,7 @@ JsonWriter putAll(Map<String, ?> values) {
 	}
 
 	JsonWriter put(String name, Object value) {
-		verifyValues(Collections.singletonMap(name, value));
+		verifyValues(Map.of(name, value));
 		this.valueMap.put(name, value);
 		return this;
 	}