[issue #788] Add more nullity annotations where relevant

 (chainable setters, static constructors, builder stuff)

doc/changelog.markdown

@@ -7,7 +7,7 @@ Lombok Changelog
 * FEATURE: In [`lombok.config`](https://projectlombok.org/features/configuration) it is possible to import other config files, even from a `.zip` or `.jar`.
 * FEATURE: You can now configure a builder's 'setter' prefixes via `@Builder(setterPrefix = "set")` for example. We discourage doing this, but if some library you use requires them, have at it. [Pull Request #2174](https://github.com/rzwitserloot/lombok/pull/2174], [Issue #1805](https://github.com/rzwitserloot/lombok/issues/1805).
 * FEATURE: If you use `@Builder`'s `@Singular`, a plural form is also generated, which has the effect of adding all elements in the passed collection. If you pass a null reference, this would result in a message-less `NullPointerException`. Now, it results in that exception but with a useful message attached (uses the same config as `@NonNull`), or alternatively via a parameter on `@Singular`, you can choose to ignore such a call (add nothing, return immediately); this can be useful when deserializing (e.g. Jackson JSON) and JPA/Hibernate code. [Issue #2221](https://github.com/rzwitserloot/lombok/issues/2221]. [singular documentation](https://projectlombok.org/features/Builder).
-* FEATURE: Tired of being unable to use `@javax.annotation.ParametersAreNonnullByDefault` or `@org.eclipse.jdt.annotation.NonNullByDefault` because then the equals method that lombok generates isn't valid? Fret no more; lombok can now add nullity annotations where relevant. Set the flavour of nullity annotation you prefer in your `lombok.config`. Applies to the return value of `toString` and `withX` methods, and the parameter of `equals`, `canEqual`, and the plural form of `@Singular` marked fields for builder classes. [Issue #788](https://github.com/rzwitserloot/lombok/issues/788)
+* FEATURE: Tired of being unable to use `@javax.annotation.ParametersAreNonnullByDefault` or `@org.eclipse.jdt.annotation.NonNullByDefault` because then the equals method that lombok generates isn't valid? Fret no more; lombok can now add nullity annotations where relevant. Set the flavour of nullity annotation you prefer in your `lombok.config`. Applies to the return value of `toString`, `withX`, chainable `setX`, static constructors, `build`, `builder`, etcetera, and the parameter of `equals`, `canEqual`, and the plural form of `@Singular` marked fields for builder classes. [Issue #788](https://github.com/rzwitserloot/lombok/issues/788)
 * BUGFIX: `lombok.experimental.Wither` has been deprecated (it has been renamed to `lombok.With`). However, the intent is that lombok still handles the old annotation in case you haven't updated your lombok dep yet. However, only a star import on `lombok.experimental.*` worked; an explicit one would cause lombok to not generate any with method. [Issue #2235](https://github.com/rzwitserloot/lombok/issues/2235)
 * BUGFIX: Referring to an inner class inside the generics on a class marked with `@SuperBuilder` would cause the error `wrong number of type arguments; required 3` [Issue #2262](https://github.com/rzwitserloot/lombok/issues/2262); fixed by github user [`@Lekanich`](https://github.com/rzwitserloot/lombok/issues/2262) - thank you!
 * BUGFIX: Some of the code generated by `@Builder` did not include `this.` prefixes when accessing fields. While semantically it didn't matter, if you use the 'add this prefix for field accesses' save action in eclipse, the save action would break. [Issue #2327](https://github.com/rzwitserloot/lombok/issues/2327)

src/core/lombok/eclipse/handlers/HandleBuilder.java

@@ -650,6 +650,7 @@ private MethodDeclaration generateToBuilderMethod(CheckerFrameworkVersion cfv, b
 			out.annotations = new Annotation[] {generateNamedAnnotation(source, CheckerFrameworkVersion.NAME__UNIQUE)};
 		}
 
+		createRelevantNonNullAnnotation(type, out);
 		out.traverse(new SetGeneratedByVisitor(source), ((TypeDeclaration) type.get()).scope);
 		return out;
 	}
@@ -796,6 +797,7 @@ public MethodDeclaration generateBuildMethod(CheckerFrameworkVersion cfv, Eclips
 			out.annotations = new Annotation[] {generateNamedAnnotation(source, CheckerFrameworkVersion.NAME__SIDE_EFFECT_FREE)};
 		}
 		out.arguments = generateBuildArgs(cfv, type, builderFields, source);
+		if (staticName == null) createRelevantNonNullAnnotation(type, out);
 		out.traverse(new SetGeneratedByVisitor(source), (ClassScope) null);
 		return out;
 	}
@@ -864,6 +866,7 @@ public MethodDeclaration generateBuilderMethod(CheckerFrameworkVersion cfv, bool
 		} else if (sefAnn != null) {
 			out.annotations = new Annotation[] {sefAnn};
 		}
+		createRelevantNonNullAnnotation(type, out);
 		out.traverse(new SetGeneratedByVisitor(source), ((TypeDeclaration) type.get()).scope);
 		return out;
 	}

src/core/lombok/eclipse/handlers/HandleConstructor.java

@@ -562,6 +562,7 @@ public MethodDeclaration createStaticConstructor(AccessLevel level, String name,
 		constructor.arguments = params.isEmpty() ? null : params.toArray(new Argument[0]);
 		constructor.statements = new Statement[] { new ReturnStatement(statement, (int) (p >> 32), (int)p) };
 
+		createRelevantNonNullAnnotation(type, constructor);
 		constructor.traverse(new SetGeneratedByVisitor(source), typeDecl.scope);
 		return constructor;
 	}

src/core/lombok/eclipse/handlers/HandleSetter.java

@@ -260,6 +260,8 @@ static MethodDeclaration createSetter(TypeDeclaration parent, boolean deprecate,
 		method.statements = statements.toArray(new Statement[0]);
 		param.annotations = copyAnnotations(source, copyableAnnotations, onParam.toArray(new Annotation[0]));
 
+		if (returnType != null && returnStatement != null) createRelevantNonNullAnnotation(sourceNode, method);
+
 		method.traverse(new SetGeneratedByVisitor(source), parent.scope);
 		return method;
 	}

src/core/lombok/eclipse/handlers/HandleSuperBuilder.java

@@ -599,6 +599,7 @@ private MethodDeclaration generateBuilderMethod(CheckerFrameworkVersion cfv, Str
 
 		if (cfv.generateUnique()) out.annotations = new Annotation[] {generateNamedAnnotation(source, CheckerFrameworkVersion.NAME__UNIQUE)};
 
+		createRelevantNonNullAnnotation(type, out);
 		out.traverse(new SetGeneratedByVisitor(source), ((TypeDeclaration) type.get()).scope);
 		return out;
 	}
@@ -633,6 +634,7 @@ private MethodDeclaration generateToBuilderMethod(CheckerFrameworkVersion cfv, S
 
 		if (cfv.generateUnique()) out.annotations = new Annotation[] {generateNamedAnnotation(source, CheckerFrameworkVersion.NAME__UNIQUE)};
 
+		createRelevantNonNullAnnotation(type, out);
 		out.traverse(new SetGeneratedByVisitor(source), ((TypeDeclaration) type.get()).scope);
 		return out;
 	}
@@ -850,8 +852,9 @@ private MethodDeclaration generateBuildMethod(CheckerFrameworkVersion cfv, Eclip
 		allocationStatement.arguments = new Expression[] {new ThisReference(0, 0)};
 		statements.add(new ReturnStatement(allocationStatement, 0, 0));
 		out.statements = statements.isEmpty() ? null : statements.toArray(new Statement[0]);
-		out.traverse(new SetGeneratedByVisitor(source), (ClassScope) null);
 		out.arguments = HandleBuilder.generateBuildArgs(cfv, builderType, builderFields, source);
+		createRelevantNonNullAnnotation(builderType, out);
+		out.traverse(new SetGeneratedByVisitor(source), (ClassScope) null);
 		return out;
 	}
 

src/core/lombok/eclipse/handlers/singulars/EclipseGuavaSingularizer.java

@@ -132,6 +132,7 @@ void generateClearMethod(CheckerFrameworkVersion cfv, boolean deprecate, TypeRef
 		md.annotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 
 		data.setGeneratedByRecursive(md);
+		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		injectMethod(builderType, md);
 	}
 
@@ -176,6 +177,7 @@ void generateSingularMethod(CheckerFrameworkVersion cfv, boolean deprecate, Type
 		md.selector = fluent ? prefixedSingularName : HandlerUtil.buildAccessorName("add", new String(data.getSingularName())).toCharArray();
 		md.annotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 
+		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		data.setGeneratedByRecursive(md);
 		HandleNonNull.INSTANCE.fix(injectMethod(builderType, md));
 	}
@@ -207,13 +209,13 @@ void generatePluralMethod(CheckerFrameworkVersion cfv, boolean deprecate, TypeRe
 
 		md.statements = statements.toArray(new Statement[0]);
 
-
 		md.arguments = new Argument[] {param};
 		md.returnType = returnType;
 		char[] prefixedSelector = data.getSetterPrefix().length == 0 ? data.getPluralName() : HandlerUtil.buildAccessorName(new String(data.getSetterPrefix()), new String(data.getPluralName())).toCharArray();
 		md.selector = fluent ? prefixedSelector : HandlerUtil.buildAccessorName("addAll", new String(data.getPluralName())).toCharArray();
 		md.annotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 
+		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		data.setGeneratedByRecursive(md);
 		injectMethod(builderType, md);
 	}

src/core/lombok/eclipse/handlers/singulars/EclipseJavaUtilListSetSingularizer.java

@@ -122,6 +122,7 @@ private void generateClearMethod(CheckerFrameworkVersion cfv, boolean deprecate,
 		md.annotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 
 		data.setGeneratedByRecursive(md);
+		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		injectMethod(builderType, md);
 	}
 
@@ -154,6 +155,7 @@ void generateSingularMethod(CheckerFrameworkVersion cfv, boolean deprecate, Type
 		md.selector = fluent ? prefixedSingularName : HandlerUtil.buildAccessorName("add", new String(data.getSingularName())).toCharArray();
 		md.annotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 
+		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		data.setGeneratedByRecursive(md);
 		HandleNonNull.INSTANCE.fix(injectMethod(builderType, md));
 	}
@@ -189,6 +191,7 @@ void generatePluralMethod(CheckerFrameworkVersion cfv, boolean deprecate, TypeRe
 		md.selector = fluent ? prefixedSelector : HandlerUtil.buildAccessorName("addAll", new String(data.getPluralName())).toCharArray();
 		md.annotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 
+		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		data.setGeneratedByRecursive(md);
 		injectMethod(builderType, md);
 	}

src/core/lombok/eclipse/handlers/singulars/EclipseJavaUtilMapSingularizer.java

@@ -191,6 +191,7 @@ private void generateClearMethod(CheckerFrameworkVersion cfv, boolean deprecate,
 		md.returnType = returnType;
 		md.annotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 
+		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		data.setGeneratedByRecursive(md);
 		injectMethod(builderType, md);
 	}
@@ -253,6 +254,7 @@ private void generateSingularMethod(CheckerFrameworkVersion cfv, boolean depreca
 		md.selector = setterName.toCharArray();
 		md.annotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 
+		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		data.setGeneratedByRecursive(md);
 		HandleNonNull.INSTANCE.fix(injectMethod(builderType, md));
 	}
@@ -326,6 +328,7 @@ private void generatePluralMethod(CheckerFrameworkVersion cfv, boolean deprecate
 		md.selector = setterName.toCharArray();
 		md.annotations = generateSelfReturnAnnotations(deprecate, cfv, data.getSource());
 
+		if (returnStatement != null) createRelevantNonNullAnnotation(builderType, md);
 		data.setGeneratedByRecursive(md);
 		injectMethod(builderType, md);
 	}

src/core/lombok/javac/handlers/HandleBuilder.java

@@ -611,7 +611,9 @@ private JCMethodDecl generateToBuilderMethod(CheckerFrameworkVersion cfv, String
 		}
 		JCBlock body = maker.Block(0, statements.toList());
 		List<JCAnnotation> annsOnMethod = cfv.generateUnique() ? List.of(maker.Annotation(genTypeRef(type, CheckerFrameworkVersion.NAME__UNIQUE), List.<JCExpression>nil())) : List.<JCAnnotation>nil();
-		return maker.MethodDef(maker.Modifiers(toJavacModifier(access), annsOnMethod), type.toName(toBuilderMethodName), namePlusTypeParamsToTypeReference(maker, type, type.toName(builderClassName), !isStatic, typeParams), List.<JCTypeParameter>nil(), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+		JCMethodDecl methodDef = maker.MethodDef(maker.Modifiers(toJavacModifier(access), annsOnMethod), type.toName(toBuilderMethodName), namePlusTypeParamsToTypeReference(maker, type, type.toName(builderClassName), !isStatic, typeParams), List.<JCTypeParameter>nil(), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+		createRelevantNonNullAnnotation(type, methodDef);
+		return methodDef;
 	}
 
 	private JCMethodDecl generateCleanMethod(java.util.List<BuilderFieldData> builderFields, JavacNode type, JCTree source) {
@@ -714,7 +716,9 @@ private JCMethodDecl generateBuildMethod(CheckerFrameworkVersion cfv, JavacNode
 
 		List<JCAnnotation> annsOnMethod = cfv.generateSideEffectFree() ? List.of(maker.Annotation(genTypeRef(type, CheckerFrameworkVersion.NAME__SIDE_EFFECT_FREE), List.<JCExpression>nil())) : List.<JCAnnotation>nil();
 		List<JCVariableDecl> params = generateBuildArgs(cfv, type, builderFields);
-		return maker.MethodDef(maker.Modifiers(toJavacModifier(access), annsOnMethod), type.toName(buildName), returnType, List.<JCTypeParameter>nil(), params, thrownExceptions, body, null);
+		JCMethodDecl methodDef = maker.MethodDef(maker.Modifiers(toJavacModifier(access), annsOnMethod), type.toName(buildName), returnType, List.<JCTypeParameter>nil(), params, thrownExceptions, body, null);
+		if (builderName == null) createRelevantNonNullAnnotation(type, methodDef);
+		return methodDef;
 	}
 
 	public static JCMethodDecl generateDefaultProvider(Name methodName, JavacNode fieldNode, List<JCTypeParameter> params) {
@@ -757,7 +761,9 @@ public JCMethodDecl generateBuilderMethod(CheckerFrameworkVersion cfv, boolean i
 		else if (annUnique != null) annsOnMethod = List.of(annUnique);
 		else if (annSef != null) annsOnMethod = List.of(annSef);
 		else annsOnMethod = List.nil();
-		return maker.MethodDef(maker.Modifiers(modifiers, annsOnMethod), type.toName(builderMethodName), namePlusTypeParamsToTypeReference(maker, type, type.toName(builderClassName), !isStatic, typeParams), copyTypeParams(source, typeParams), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+		JCMethodDecl methodDef = maker.MethodDef(maker.Modifiers(modifiers, annsOnMethod), type.toName(builderMethodName), namePlusTypeParamsToTypeReference(maker, type, type.toName(builderClassName), !isStatic, typeParams), copyTypeParams(source, typeParams), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+		createRelevantNonNullAnnotation(type, methodDef);
+		return methodDef;
 	}
 
 	public void generateBuilderFields(JavacNode builderType, java.util.List<BuilderFieldData> builderFields, JCTree source) {

src/core/lombok/javac/handlers/HandleConstructor.java

@@ -489,6 +489,8 @@ public JCMethodDecl createStaticConstructor(String name, AccessLevel level, Java
 		JCReturn returnStatement = maker.Return(maker.NewClass(null, List.<JCExpression>nil(), constructorType, args.toList(), null));
 		JCBlock body = maker.Block(0, List.<JCStatement>of(returnStatement));
 
-		return recursiveSetGeneratedBy(maker.MethodDef(mods, typeNode.toName(name), returnType, typeParams.toList(), params.toList(), List.<JCExpression>nil(), body, null), source, typeNode.getContext());
+		JCMethodDecl methodDef = maker.MethodDef(mods, typeNode.toName(name), returnType, typeParams.toList(), params.toList(), List.<JCExpression>nil(), body, null);
+		createRelevantNonNullAnnotation(typeNode, methodDef);
+		return recursiveSetGeneratedBy(methodDef, source, typeNode.getContext());
 	}
 }

src/core/lombok/javac/handlers/HandleSetter.java

@@ -277,8 +277,10 @@ public static JCMethodDecl createSetter(long access, boolean deprecate, JavacNod
 			annsOnMethod = annsOnMethod.prepend(treeMaker.Annotation(genJavaLangTypeRef(field, "Deprecated"), List.<JCExpression>nil()));
 		}
 
-		JCMethodDecl decl = recursiveSetGeneratedBy(treeMaker.MethodDef(treeMaker.Modifiers(access, annsOnMethod), methodName, methodType,
-			methodGenericParams, parameters, throwsClauses, methodBody, annotationMethodDefaultValue), source.get(), field.getContext());
+		JCMethodDecl methodDef = treeMaker.MethodDef(treeMaker.Modifiers(access, annsOnMethod), methodName, methodType,
+			methodGenericParams, parameters, throwsClauses, methodBody, annotationMethodDefaultValue);
+		if (returnStatement != null) createRelevantNonNullAnnotation(source, methodDef);
+		JCMethodDecl decl = recursiveSetGeneratedBy(methodDef, source.get(), field.getContext());
 		copyJavadoc(field, decl, CopyJavadoc.SETTER, returnStatement != null);
 		return decl;
 	}

src/core/lombok/javac/handlers/HandleSuperBuilder.java

@@ -569,7 +569,9 @@ private JCMethodDecl generateBuilderMethod(CheckerFrameworkVersion cfv, String b
 		JCTypeApply returnType = maker.TypeApply(namePlusTypeParamsToTypeReference(maker, type, type.toName(builderClassName), false, List.<JCTypeParameter>nil()), typeParameterNames.toList());
 
 		List<JCAnnotation> annsOnMethod = cfv.generateUnique() ? List.of(maker.Annotation(genTypeRef(type, CheckerFrameworkVersion.NAME__SIDE_EFFECT_FREE), List.<JCExpression>nil())) : List.<JCAnnotation>nil();
-		return maker.MethodDef(maker.Modifiers(modifiers, annsOnMethod), type.toName(builderMethodName), returnType, copyTypeParams(source, typeParams), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+		JCMethodDecl methodDef = maker.MethodDef(maker.Modifiers(modifiers, annsOnMethod), type.toName(builderMethodName), returnType, copyTypeParams(source, typeParams), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+		createRelevantNonNullAnnotation(type, methodDef);
+		return methodDef;
 	}
 
 	/**
@@ -604,7 +606,9 @@ private JCMethodDecl generateToBuilderMethod(CheckerFrameworkVersion cfv, String
 		JCTypeApply returnType = maker.TypeApply(namePlusTypeParamsToTypeReference(maker, type, type.toName(builderClassName), false, List.<JCTypeParameter>nil()), typeParameterNames.toList());
 
 		List<JCAnnotation> annsOnMethod = cfv.generateUnique() ? List.of(maker.Annotation(genTypeRef(type, CheckerFrameworkVersion.NAME__SIDE_EFFECT_FREE), List.<JCExpression>nil())) : List.<JCAnnotation>nil();
-		return maker.MethodDef(maker.Modifiers(modifiers, annsOnMethod), type.toName(TO_BUILDER_METHOD_NAME), returnType, List.<JCTypeParameter>nil(), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+		JCMethodDecl methodDef = maker.MethodDef(maker.Modifiers(modifiers, annsOnMethod), type.toName(TO_BUILDER_METHOD_NAME), returnType, List.<JCTypeParameter>nil(), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+		createRelevantNonNullAnnotation(type, methodDef);
+		return methodDef;
 	}
 
 	/**
@@ -808,7 +812,9 @@ private JCMethodDecl generateBuildMethod(CheckerFrameworkVersion cfv, String bui
 		JCModifiers modifiers = maker.Modifiers(Flags.PUBLIC, annsOnMethod);
 
 		List<JCVariableDecl> params = HandleBuilder.generateBuildArgs(cfv, type, builderFields);
-		return maker.MethodDef(modifiers, type.toName(buildName), cloneSelfType(returnType), List.<JCTypeParameter>nil(), params, thrownExceptions, body, null);
+		JCMethodDecl methodDef = maker.MethodDef(modifiers, type.toName(buildName), cloneSelfType(returnType), List.<JCTypeParameter>nil(), params, thrownExceptions, body, null);
+		createRelevantNonNullAnnotation(type, methodDef);
+		return methodDef;
 	}
 
 	private JCMethodDecl generateCleanMethod(java.util.List<BuilderFieldData> builderFields, JavacNode type, JCTree source) {

src/core/lombok/javac/handlers/JavacSingularsRecipes.java

@@ -288,6 +288,7 @@ private void finishAndInjectMethod(CheckerFrameworkVersion cfv, JavacTreeMaker m
 
 			JCMethodDecl method = maker.MethodDef(mods, methodName, returnType, typeParams, jcVariableDecls, thrown, body, null);
 			recursiveSetGeneratedBy(method, source, builderType.getContext());
+			if (returnStatement != null) createRelevantNonNullAnnotation(builderType, method);
 			injectMethod(builderType, method);
 		}