Merge branch 'janrieke-superBuilder'

11 files changed, 852 insertions, 100 deletions

diff --git a/src/core/lombok/javac/handlers/HandleBuilder.java b/src/core/lombok/javac/handlers/HandleBuilder.java
index fb3b45a4..d56d6ac2 100644
--- a/src/core/lombok/javac/handlers/HandleBuilder.java
+++ b/src/core/lombok/javac/handlers/HandleBuilder.java
@@ -550,7 +550,7 @@ public class HandleBuilder extends JavacAnnotationHandler<Builder> {
 		
 		for (BuilderFieldData bfd : builderFields) {
 			if (bfd.singularData != null && bfd.singularData.getSingularizer() != null) {
-				bfd.singularData.getSingularizer().appendBuildCode(bfd.singularData, type, source, statements, bfd.name);
+				bfd.singularData.getSingularizer().appendBuildCode(bfd.singularData, type, source, statements, bfd.name, "this");
 			}
 		}
 		
diff --git a/src/core/lombok/javac/handlers/HandleBuilderDefault.java b/src/core/lombok/javac/handlers/HandleBuilderDefault.java
index 4c4ba0e8..af45a620 100644
--- a/src/core/lombok/javac/handlers/HandleBuilderDefault.java
+++ b/src/core/lombok/javac/handlers/HandleBuilderDefault.java
@@ -31,6 +31,7 @@ import lombok.Builder;
 import lombok.core.AST.Kind;
 import lombok.core.AnnotationValues;
 import lombok.core.HandlerPriority;
+import lombok.experimental.SuperBuilder;
 import lombok.javac.JavacAnnotationHandler;
 import lombok.javac.JavacNode;
 
@@ -41,8 +42,9 @@ public class HandleBuilderDefault extends JavacAnnotationHandler<Builder.Default
 		JavacNode annotatedField = annotationNode.up();
 		if (annotatedField.getKind() != Kind.FIELD) return;
 		JavacNode classWithAnnotatedField = annotatedField.up();
-		if (!hasAnnotation(Builder.class, classWithAnnotatedField) && !hasAnnotation("lombok.experimental.Builder", classWithAnnotatedField)) {
-			annotationNode.addWarning("@Builder.Default requires @Builder on the class for it to mean anything.");
+		if (!hasAnnotation(Builder.class, classWithAnnotatedField) && !hasAnnotation("lombok.experimental.Builder", classWithAnnotatedField)
+				&& !hasAnnotation(SuperBuilder.class, classWithAnnotatedField)) {
+			annotationNode.addWarning("@Builder.Default requires @Builder or @SuperBuilder on the class for it to mean anything.");
 			deleteAnnotationIfNeccessary(annotationNode, Builder.Default.class);
 		}
 	}
diff --git a/src/core/lombok/javac/handlers/HandleSetter.java b/src/core/lombok/javac/handlers/HandleSetter.java
index 4e3c9576..0ddaa7d7 100644
--- a/src/core/lombok/javac/handlers/HandleSetter.java
+++ b/src/core/lombok/javac/handlers/HandleSetter.java
@@ -207,6 +207,17 @@ public class HandleSetter extends JavacAnnotationHandler<Setter> {
 	}
 	
 	public static JCMethodDecl createSetter(long access, boolean deprecate, JavacNode field, JavacTreeMaker treeMaker, String setterName, Name booleanFieldToSet, boolean shouldReturnThis, JavacNode source, List<JCAnnotation> onMethod, List<JCAnnotation> onParam) {
+		JCExpression returnType = null;
+		JCReturn returnStatement = null;
+		if (shouldReturnThis) {
+			returnType = cloneSelfType(field);
+			returnStatement = treeMaker.Return(treeMaker.Ident(field.toName("this")));
+		}
+		
+		return createSetter(access, deprecate, field, treeMaker, setterName, booleanFieldToSet, returnType, returnStatement, source, onMethod, onParam);
+	}
+	
+	public static JCMethodDecl createSetter(long access, boolean deprecate, JavacNode field, JavacTreeMaker treeMaker, String setterName, Name booleanFieldToSet, JCExpression methodType, JCStatement returnStatement, JavacNode source, List<JCAnnotation> onMethod, List<JCAnnotation> onParam) {
 		if (setterName == null) return null;
 		
 		JCVariableDecl fieldDecl = (JCVariableDecl) field.get();
@@ -237,21 +248,13 @@ public class HandleSetter extends JavacAnnotationHandler<Setter> {
 			statements.append(treeMaker.Exec(setBool));
 		}
 		
-		JCExpression methodType = null;
-		if (shouldReturnThis) {
-			methodType = cloneSelfType(field);
-		}
-		
 		if (methodType == null) {
 			//WARNING: Do not use field.getSymbolTable().voidType - that field has gone through non-backwards compatible API changes within javac1.6.
 			methodType = treeMaker.Type(Javac.createVoidType(field.getSymbolTable(), CTC_VOID));
-			shouldReturnThis = false;
+			returnStatement = null;
 		}
 		
-		if (shouldReturnThis) {
-			JCReturn returnStatement = treeMaker.Return(treeMaker.Ident(field.toName("this")));
-			statements.append(returnStatement);
-		}
+		if (returnStatement != null) statements.append(returnStatement);
 		
 		JCBlock methodBody = treeMaker.Block(0, statements.toList());
 		List<JCTypeParameter> methodGenericParams = List.nil();
diff --git a/src/core/lombok/javac/handlers/HandleSuperBuilder.java b/src/core/lombok/javac/handlers/HandleSuperBuilder.java
new file mode 100644
index 00000000..38fec2f6
--- /dev/null
+++ b/src/core/lombok/javac/handlers/HandleSuperBuilder.java
@@ -0,0 +1,738 @@
+/*
+ * Copyright (C) 2013-2018 The Project Lombok Authors.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.javac.handlers;
+
+import static lombok.core.handlers.HandlerUtil.*;
+import static lombok.javac.Javac.*;
+import static lombok.javac.handlers.JavacHandlerUtil.*;
+
+import java.util.ArrayList;
+
+import org.mangosdk.spi.ProviderFor;
+
+import com.sun.tools.javac.code.BoundKind;
+import com.sun.tools.javac.code.Flags;
+import com.sun.tools.javac.tree.JCTree;
+import com.sun.tools.javac.tree.JCTree.JCAnnotation;
+import com.sun.tools.javac.tree.JCTree.JCBlock;
+import com.sun.tools.javac.tree.JCTree.JCClassDecl;
+import com.sun.tools.javac.tree.JCTree.JCExpression;
+import com.sun.tools.javac.tree.JCTree.JCFieldAccess;
+import com.sun.tools.javac.tree.JCTree.JCIdent;
+import com.sun.tools.javac.tree.JCTree.JCIf;
+import com.sun.tools.javac.tree.JCTree.JCMethodDecl;
+import com.sun.tools.javac.tree.JCTree.JCMethodInvocation;
+import com.sun.tools.javac.tree.JCTree.JCModifiers;
+import com.sun.tools.javac.tree.JCTree.JCStatement;
+import com.sun.tools.javac.tree.JCTree.JCTypeApply;
+import com.sun.tools.javac.tree.JCTree.JCTypeParameter;
+import com.sun.tools.javac.tree.JCTree.JCVariableDecl;
+import com.sun.tools.javac.tree.JCTree.JCWildcard;
+import com.sun.tools.javac.util.List;
+import com.sun.tools.javac.util.ListBuffer;
+import com.sun.tools.javac.util.Name;
+
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Builder.ObtainVia;
+import lombok.ConfigurationKeys;
+import lombok.Singular;
+import lombok.ToString;
+import lombok.core.AST.Kind;
+import lombok.core.AnnotationValues;
+import lombok.core.HandlerPriority;
+import lombok.core.handlers.HandlerUtil;
+import lombok.core.handlers.InclusionExclusionUtils.Included;
+import lombok.experimental.NonFinal;
+import lombok.experimental.SuperBuilder;
+import lombok.javac.Javac;
+import lombok.javac.JavacAnnotationHandler;
+import lombok.javac.JavacNode;
+import lombok.javac.JavacTreeMaker;
+import lombok.javac.handlers.JavacHandlerUtil.MemberExistsResult;
+import lombok.javac.handlers.JavacSingularsRecipes.ExpressionMaker;
+import lombok.javac.handlers.JavacSingularsRecipes.StatementMaker;
+import lombok.javac.handlers.JavacSingularsRecipes.JavacSingularizer;
+import lombok.javac.handlers.JavacSingularsRecipes.SingularData;
+
+@ProviderFor(JavacAnnotationHandler.class)
+@HandlerPriority(-1024) //-2^10; to ensure we've picked up @FieldDefault's changes (-2048) but @Value hasn't removed itself yet (-512), so that we can error on presence of it on the builder classes.
+public class HandleSuperBuilder extends JavacAnnotationHandler<SuperBuilder> {
+	private static final String SELF_METHOD = "self";
+	
+	private static class BuilderFieldData {
+		JCExpression type;
+		Name rawName;
+		Name name;
+		Name nameOfSetFlag;
+		SingularData singularData;
+		ObtainVia obtainVia;
+		JavacNode obtainViaNode;
+		JavacNode originalFieldNode;
+		
+		java.util.List<JavacNode> createdFields = new ArrayList<JavacNode>();
+	}
+	
+	@Override
+	public void handle(AnnotationValues<SuperBuilder> annotation, JCAnnotation ast, JavacNode annotationNode) {
+		handleExperimentalFlagUsage(annotationNode, ConfigurationKeys.SUPERBUILDER_FLAG_USAGE, "@SuperBuilder");
+		
+		SuperBuilder superbuilderAnnotation = annotation.getInstance();
+		deleteAnnotationIfNeccessary(annotationNode, SuperBuilder.class);
+		
+		String builderMethodName = superbuilderAnnotation.builderMethodName();
+		String buildMethodName = superbuilderAnnotation.buildMethodName();
+		
+		if (builderMethodName == null) builderMethodName = "builder";
+		if (buildMethodName == null) buildMethodName = "build";
+		
+		if (!checkName("builderMethodName", builderMethodName, annotationNode)) return;
+		if (!checkName("buildMethodName", buildMethodName, annotationNode)) return;
+		
+		JavacNode tdParent = annotationNode.up();
+		
+		java.util.List<BuilderFieldData> builderFields = new ArrayList<BuilderFieldData>();
+		JCExpression returnType;
+		List<JCTypeParameter> typeParams = List.nil();
+		List<JCExpression> thrownExceptions = List.nil();
+		List<JCExpression> superclassTypeParams = List.nil();
+		
+		boolean addCleaning = false;
+		
+		if (!(tdParent.get() instanceof JCClassDecl)) {
+			annotationNode.addError("@SuperBuilder is only supported on types.");
+			return;
+		}
+		
+		// Gather all fields of the class that should be set by the builder.
+		JCClassDecl td = (JCClassDecl) tdParent.get();
+		ListBuffer<JavacNode> allFields = new ListBuffer<JavacNode>();
+		boolean valuePresent = (hasAnnotation(lombok.Value.class, tdParent) || hasAnnotation("lombok.experimental.Value", tdParent));
+		for (JavacNode fieldNode : HandleConstructor.findAllFields(tdParent, true)) {
+			JCVariableDecl fd = (JCVariableDecl) fieldNode.get();
+			JavacNode isDefault = findAnnotation(Builder.Default.class, fieldNode, true);
+			boolean isFinal = (fd.mods.flags & Flags.FINAL) != 0 || (valuePresent && !hasAnnotation(NonFinal.class, fieldNode));
+			BuilderFieldData bfd = new BuilderFieldData();
+			bfd.rawName = fd.name;
+			bfd.name = removePrefixFromField(fieldNode);
+			bfd.type = fd.vartype;
+			bfd.singularData = getSingularData(fieldNode);
+			bfd.originalFieldNode = fieldNode;
+			
+			if (bfd.singularData != null && isDefault != null) {
+				isDefault.addError("@Builder.Default and @Singular cannot be mixed.");
+				isDefault = null;
+			}
+			
+			if (fd.init == null && isDefault != null) {
+				isDefault.addWarning("@Builder.Default requires an initializing expression (' = something;').");
+				isDefault = null;
+			}
+			
+			if (fd.init != null && isDefault == null) {
+				if (isFinal) continue;
+				fieldNode.addWarning("@SuperBuilder will ignore the initializing expression entirely. If you want the initializing expression to serve as default, add @Builder.Default. If it is not supposed to be settable during building, make the field final.");
+			}
+			
+			if (isDefault != null) {
+				bfd.nameOfSetFlag = tdParent.toName(bfd.name + "$set");
+				// The @Builder annotation removes the initializing expression on the field and moves
+				// it to a method called "$default$FIELDNAME". This method is then called upon building.
+				// We do NOT do this, because this is unexpected and may lead to bugs when using other 
+				// constructors (see, e.g., issue #1347).
+				// Instead, we keep the init expression and only set a new value in the builder-based
+				// constructor if it was set in the builder. Drawback is that the init expression is
+				// always executed, even if it was unnecessary because its value is overwritten by the 
+				// builder.
+				// TODO: Once the issue is resolved in @Builder, we can adapt the solution here. 
+			}
+			addObtainVia(bfd, fieldNode);
+			builderFields.add(bfd);
+			allFields.append(fieldNode);
+		}
+		
+		// Set the names of the builder classes.
+		String builderClassName = td.name.toString() + "Builder";
+		String builderImplClassName = builderClassName + "Impl";
+		JCTree extendsClause = Javac.getExtendsClause(td);
+		JCExpression superclassBuilderClassExpression = null;
+		if (extendsClause instanceof JCTypeApply) {
+			// Remember the type arguments, because we need them for the extends clause of our abstract builder class.
+			superclassTypeParams = ((JCTypeApply) extendsClause).getTypeArguments();
+			// A class name with a generics type, e.g., "Superclass<A>".
+			extendsClause = ((JCTypeApply) extendsClause).getType();
+		}
+		if (extendsClause instanceof JCFieldAccess) {
+			Name superclassClassName = ((JCFieldAccess)extendsClause).getIdentifier();
+			String superclassBuilderClassName = superclassClassName + "Builder";
+			superclassBuilderClassExpression = tdParent.getTreeMaker().Select((JCFieldAccess) extendsClause,
+					tdParent.toName(superclassBuilderClassName));
+		} else if (extendsClause != null) {
+			String superclassBuilderClassName = extendsClause.toString() + "Builder";
+			superclassBuilderClassExpression = chainDots(tdParent, extendsClause.toString(), superclassBuilderClassName);
+		}
+		// If there is no superclass, superclassBuilderClassExpression is still == null at this point.
+		// You can use it to check whether to inherit or not.
+		
+		returnType = namePlusTypeParamsToTypeReference(tdParent.getTreeMaker(), td.name, td.typarams);
+		typeParams = td.typarams;
+		
+		// <C, B> are the generics for our builder.
+		String classGenericName = "C";
+		String builderGenericName = "B";
+		// If these generics' names collide with any generics on the annotated class, modify them.
+		// For instance, if there are generics <B, B2, C> on the annotated class, use "C2" and "B3" for our builder.
+		java.util.List<String> typeParamStrings = new ArrayList<String>();
+		for (JCTypeParameter typeParam : typeParams) typeParamStrings.add(typeParam.getName().toString());
+		classGenericName = generateNonclashingNameFor(classGenericName, typeParamStrings);
+		builderGenericName = generateNonclashingNameFor(builderGenericName, typeParamStrings);
+		
+		thrownExceptions = List.nil();
+		
+		// Check validity of @ObtainVia fields, and add check if adding cleaning for @Singular is necessary.
+		for (BuilderFieldData bfd : builderFields) {
+			if (bfd.singularData != null && bfd.singularData.getSingularizer() != null) {
+				if (bfd.singularData.getSingularizer().requiresCleaning()) {
+					addCleaning = true;
+					break;
+				}
+			}
+			if (bfd.obtainVia != null) {
+				if (bfd.obtainVia.field().isEmpty() == bfd.obtainVia.method().isEmpty()) {
+					bfd.obtainViaNode.addError("The syntax is either @ObtainVia(field = \"fieldName\") or @ObtainVia(method = \"methodName\").");
+					return;
+				}
+				if (bfd.obtainVia.method().isEmpty() && bfd.obtainVia.isStatic()) {
+					bfd.obtainViaNode.addError("@ObtainVia(isStatic = true) is not valid unless 'method' has been set.");
+					return;
+				}
+			}
+		}
+		
+		// Create the abstract builder class.
+		JavacNode builderType = findInnerClass(tdParent, builderClassName);
+		if (builderType == null) {
+			builderType = generateBuilderAbstractClass(annotationNode, tdParent, builderClassName, superclassBuilderClassExpression,
+					typeParams, superclassTypeParams, ast, classGenericName, builderGenericName);
+		} else {
+			annotationNode.addError("@SuperBuilder does not support customized builders. Use @Builder instead.");
+			return;
+		}
+		
+		// Generate the fields in the abstract builder class that hold the values for the instance.
+		generateBuilderFields(builderType, builderFields, ast);
+		if (addCleaning) {
+			JavacTreeMaker maker = builderType.getTreeMaker();
+			JCVariableDecl uncleanField = maker.VarDef(maker.Modifiers(Flags.PRIVATE), builderType.toName("$lombokUnclean"), maker.TypeIdent(CTC_BOOLEAN), null);
+			injectFieldAndMarkGenerated(builderType, uncleanField);
+		}
+		
+		// Generate abstract self() and build() methods in the abstract builder.
+		injectMethod(builderType, generateAbstractSelfMethod(tdParent, superclassBuilderClassExpression != null, builderGenericName));
+		injectMethod(builderType, generateAbstractBuildMethod(tdParent, buildMethodName, superclassBuilderClassExpression != null, classGenericName));
+		
+		// Create the setter methods in the abstract builder.
+		for (BuilderFieldData bfd : builderFields) {
+			generateSetterMethodsForBuilder(builderType, bfd, annotationNode, builderGenericName);
+		}
+		
+		// Create the toString() method for the abstract builder.
+		java.util.List<Included<JavacNode, ToString.Include>> fieldNodes = new ArrayList<Included<JavacNode, ToString.Include>>();
+		for (BuilderFieldData bfd : builderFields) {
+			for (JavacNode f : bfd.createdFields) {
+				fieldNodes.add(new Included<JavacNode, ToString.Include>(f, null, true));
+			}
+		}
+		
+		// Let toString() call super.toString() if there is a superclass, so that it also shows fields from the superclass' builder.
+		JCMethodDecl toStringMethod = HandleToString.createToString(builderType, fieldNodes, true, superclassBuilderClassExpression != null, FieldAccess.ALWAYS_FIELD, ast);
+		if (toStringMethod != null) injectMethod(builderType, toStringMethod);
+		
+		// If clean methods are requested, add them now.
+		if (addCleaning) injectMethod(builderType, generateCleanMethod(builderFields, builderType, ast));
+		
+		recursiveSetGeneratedBy(builderType.get(), ast, annotationNode.getContext());
+		
+		if ((td.mods.flags & Flags.ABSTRACT) == 0) {
+			// Only non-abstract classes get the Builder implementation.
+			
+			// Create the builder implementation class.
+			JavacNode builderImplType = findInnerClass(tdParent, builderImplClassName);
+			if (builderImplType == null) {
+				builderImplType = generateBuilderImplClass(annotationNode, tdParent, builderImplClassName, builderClassName, typeParams, ast);
+			} else {
+				annotationNode.addError("@SuperBuilder does not support customized builders. Use @Builder instead.");
+				return;
+			}
+			
+			// Create a simple constructor for the BuilderImpl class.
+			JCMethodDecl cd = HandleConstructor.createConstructor(AccessLevel.PRIVATE, List.<JCAnnotation>nil(), builderImplType, List.<JavacNode>nil(), false, annotationNode);
+			if (cd != null) injectMethod(builderImplType, cd);
+			
+			// Create the self() and build() methods in the BuilderImpl.
+			injectMethod(builderImplType, generateSelfMethod(builderImplType));
+			injectMethod(builderImplType, generateBuildMethod(buildMethodName, returnType, builderImplType, thrownExceptions));
+			
+			recursiveSetGeneratedBy(builderImplType.get(), ast, annotationNode.getContext());
+		}
+		
+		// Generate a constructor in the annotated class that takes a builder as argument.
+		generateBuilderBasedConstructor(tdParent, typeParams, builderFields, annotationNode, builderClassName,
+				superclassBuilderClassExpression != null);
+		
+		if ((td.mods.flags & Flags.ABSTRACT) == 0) {
+			// Only non-abstract classes get the Builder implementation and the builder() method.
+			
+			// Add the builder() method to the annotated class.
+			// Allow users to specify their own builder() methods, e.g., to provide default values.
+			if (methodExists(builderMethodName, tdParent, -1) == MemberExistsResult.NOT_EXISTS) {
+				JCMethodDecl builderMethod = generateBuilderMethod(builderMethodName, builderClassName, builderImplClassName, annotationNode, tdParent, typeParams);
+				recursiveSetGeneratedBy(builderMethod, ast, annotationNode.getContext());
+				if (builderMethod != null) injectMethod(tdParent, builderMethod);
+			}
+		}
+	}
+	
+	/**
+	 * Creates and returns the abstract builder class and injects it into the annotated class.
+	 */
+	private JavacNode generateBuilderAbstractClass(JavacNode source, JavacNode tdParent, String builderClass,
+			JCExpression superclassBuilderClassExpression, List<JCTypeParameter> typeParams,
+			List<JCExpression> superclassTypeParams, JCAnnotation ast, String classGenericName, String builderGenericName) {
+		
+		JavacTreeMaker maker = tdParent.getTreeMaker();
+		JCModifiers mods = maker.Modifiers(Flags.STATIC | Flags.ABSTRACT | Flags.PUBLIC);
+		
+		// Keep any type params of the annotated class.
+		ListBuffer<JCTypeParameter> allTypeParams = new ListBuffer<JCTypeParameter>();
+		allTypeParams.addAll(copyTypeParams(source, typeParams));
+		// Add builder-specific type params required for inheritable builders.
+		// 1. The return type for the build() method, named "C", which extends the annotated class.
+		JCExpression annotatedClass = maker.Ident(tdParent.toName(tdParent.getName()));
+		if (typeParams.nonEmpty()) {
+			// Add type params of the annotated class.
+			annotatedClass = maker.TypeApply(annotatedClass, getTypeParamExpressions(typeParams, maker).toList());
+		}
+		allTypeParams.add(maker.TypeParameter(tdParent.toName(classGenericName), List.<JCExpression>of(annotatedClass)));
+		// 2. The return type for all setter methods, named "B", which extends this builder class.
+		Name builderClassName = tdParent.toName(builderClass);
+		ListBuffer<JCExpression> typeParamsForBuilder = getTypeParamExpressions(typeParams, maker);
+		typeParamsForBuilder.add(maker.Ident(tdParent.toName(classGenericName)));
+		typeParamsForBuilder.add(maker.Ident(tdParent.toName(builderGenericName)));
+		JCTypeApply typeApply = maker.TypeApply(maker.Ident(builderClassName), typeParamsForBuilder.toList());
+		allTypeParams.add(maker.TypeParameter(tdParent.toName(builderGenericName), List.<JCExpression>of(typeApply)));
+		
+		JCExpression extending = null;
+		if (superclassBuilderClassExpression != null) {
+			// If the annotated class extends another class, we want this builder to extend the builder of the superclass.
+			// 1. Add the type parameters of the superclass.
+			typeParamsForBuilder = getTypeParamExpressions(superclassTypeParams, maker);
+			// 2. Add the builder type params <C, B>.
+			typeParamsForBuilder.add(maker.Ident(tdParent.toName(classGenericName)));
+			typeParamsForBuilder.add(maker.Ident(tdParent.toName(builderGenericName)));
+			extending = maker.TypeApply(superclassBuilderClassExpression, typeParamsForBuilder.toList());
+		}
+		
+		JCClassDecl builder = maker.ClassDef(mods, builderClassName, allTypeParams.toList(), extending, List.<JCExpression>nil(), List.<JCTree>nil());
+		return injectType(tdParent, builder);
+	}
+	
+	/**
+	 * Creates and returns the concrete builder implementation class and injects it into the annotated class.
+	 */
+	private JavacNode generateBuilderImplClass(JavacNode source, JavacNode tdParent, String builderImplClass, String builderAbstractClass, List<JCTypeParameter> typeParams, JCAnnotation ast) {
+		JavacTreeMaker maker = tdParent.getTreeMaker();
+		JCModifiers mods = maker.Modifiers(Flags.STATIC | Flags.PRIVATE | Flags.FINAL);
+		
+		// Extend the abstract builder.
+		JCExpression extending = maker.Ident(tdParent.toName(builderAbstractClass));
+		// Add any type params of the annotated class.
+		ListBuffer<JCTypeParameter> allTypeParams = new ListBuffer<JCTypeParameter>();
+		allTypeParams.addAll(copyTypeParams(source, typeParams));
+		// Add builder-specific type params required for inheritable builders.
+		// 1. The return type for the build() method (named "C" in the abstract builder), which is the annotated class.
+		JCExpression annotatedClass = maker.Ident(tdParent.toName(tdParent.getName()));
+		if (typeParams.nonEmpty()) {
+			// Add type params of the annotated class.
+			annotatedClass = maker.TypeApply(annotatedClass, getTypeParamExpressions(typeParams, maker).toList());
+		}
+		// 2. The return type for all setter methods (named "B" in the abstract builder), which is this builder class.
+		JCExpression builderImplClassExpression = maker.Ident(tdParent.toName(builderImplClass));
+		if (typeParams.nonEmpty()) {
+			builderImplClassExpression = maker.TypeApply(builderImplClassExpression, getTypeParamExpressions(typeParams, maker).toList());
+		}
+		ListBuffer<JCExpression> typeParamsForBuilder = getTypeParamExpressions(typeParams, maker);
+		typeParamsForBuilder.add(annotatedClass);
+		typeParamsForBuilder.add(builderImplClassExpression);
+		extending = maker.TypeApply(extending, typeParamsForBuilder.toList());
+		
+		JCClassDecl builder = maker.ClassDef(mods, tdParent.toName(builderImplClass), copyTypeParams(source, typeParams), extending, List.<JCExpression>nil(), List.<JCTree>nil());
+		return injectType(tdParent, builder);
+	}
+
+	/**
+	 * Generates a constructor that has a builder as the only parameter.
+	 * The values from the builder are used to initialize the fields of new instances.
+	 *
+	 * @param typeNode
+	 *            the type (with the {@code @Builder} annotation) for which a
+	 *            constructor should be generated.
+	 * @param typeParams
+	 * @param builderFields a list of fields in the builder which should be assigned to new instances.
+	 * @param source the annotation (used for setting source code locations for the generated code).
+	 * @param callBuilderBasedSuperConstructor
+	 *            If {@code true}, the constructor will explicitly call a super
+	 *            constructor with the builder as argument. Requires
+	 *            {@code builderClassAsParameter != null}.
+	 */
+	private void generateBuilderBasedConstructor(JavacNode typeNode, List<JCTypeParameter> typeParams, java.util.List<BuilderFieldData> builderFields, JavacNode source, String builderClassName, boolean callBuilderBasedSuperConstructor) {
+		JavacTreeMaker maker = typeNode.getTreeMaker();
+		
+		AccessLevel level = AccessLevel.PROTECTED;
+		
+		ListBuffer<JCStatement> nullChecks = new ListBuffer<JCStatement>();
+		ListBuffer<JCStatement> statements = new ListBuffer<JCStatement>();
+		
+		Name builderVariableName = typeNode.toName("b");
+		for (BuilderFieldData bfd : builderFields) {
+			List<JCAnnotation> nonNulls = findAnnotations(bfd.originalFieldNode, NON_NULL_PATTERN);
+			if (!nonNulls.isEmpty()) {
+				JCStatement nullCheck = generateNullCheck(maker, bfd.originalFieldNode, source);
+				if (nullCheck != null) nullChecks.append(nullCheck);
+			}
+			
+			JCExpression rhs;
+			if (bfd.singularData != null && bfd.singularData.getSingularizer() != null) {
+				bfd.singularData.getSingularizer().appendBuildCode(bfd.singularData, bfd.originalFieldNode, bfd.type, statements, bfd.name, "b");
+				rhs = maker.Ident(bfd.singularData.getPluralName());
+			} else {
+				rhs = maker.Select(maker.Ident(builderVariableName), bfd.rawName);
+			}
+			JCFieldAccess thisX = maker.Select(maker.Ident(typeNode.toName("this")), bfd.rawName);
+			
+			JCStatement assign = maker.Exec(maker.Assign(thisX, rhs));
+			
+			// In case of @Builder.Default, only set the value if it really was set in the builder.
+			if (bfd.nameOfSetFlag != null) {
+				JCFieldAccess setField = maker.Select(maker.Ident(builderVariableName), bfd.nameOfSetFlag);
+				JCIf ifSet = maker.If(setField, assign, null);
+				statements.append(ifSet);
+			} else {
+				statements.append(assign);
+			}
+		}
+		
+		JCModifiers mods = maker.Modifiers(toJavacModifier(level), List.<JCAnnotation>nil());
+		
+		// Create a constructor that has just the builder as parameter.
+		ListBuffer<JCVariableDecl> params = new ListBuffer<JCVariableDecl>();
+		long flags = JavacHandlerUtil.addFinalIfNeeded(Flags.PARAMETER, typeNode.getContext());
+		Name builderClassname = typeNode.toName(builderClassName);
+		// First add all generics that are present on the parent type.
+		ListBuffer<JCExpression> typeParamsForBuilderParameter = getTypeParamExpressions(typeParams, maker);
+		// Now add the <?, ?>.
+		JCWildcard wildcard = maker.Wildcard(maker.TypeBoundKind(BoundKind.UNBOUND), null);
+		typeParamsForBuilderParameter.add(wildcard);
+		wildcard = maker.Wildcard(maker.TypeBoundKind(BoundKind.UNBOUND), null);
+		typeParamsForBuilderParameter.add(wildcard);
+		JCTypeApply paramType = maker.TypeApply(maker.Ident(builderClassname), typeParamsForBuilderParameter.toList());
+		JCVariableDecl param = maker.VarDef(maker.Modifiers(flags), builderVariableName, paramType, null);
+		params.append(param);
+		
+		if (callBuilderBasedSuperConstructor) {
+			// The first statement must be the call to the super constructor.
+			JCMethodInvocation callToSuperConstructor = maker.Apply(List.<JCExpression>nil(),
+					maker.Ident(typeNode.toName("super")),
+					List.<JCExpression>of(maker.Ident(builderVariableName)));
+			statements.prepend(maker.Exec(callToSuperConstructor));
+		}
+		
+		JCMethodDecl constr = recursiveSetGeneratedBy(maker.MethodDef(mods, typeNode.toName("<init>"),
+			null, List.<JCTypeParameter>nil(), params.toList(), List.<JCExpression>nil(),
+			maker.Block(0L, nullChecks.appendList(statements).toList()), null), source.get(), typeNode.getContext());
+		
+		injectMethod(typeNode, constr, null, Javac.createVoidType(typeNode.getSymbolTable(), CTC_VOID));
+	}
+	
+	private JCMethodDecl generateBuilderMethod(String builderMethodName, String builderClassName, String builderImplClassName, JavacNode source, JavacNode type, List<JCTypeParameter> typeParams) {
+		JavacTreeMaker maker = type.getTreeMaker();
+		
+		ListBuffer<JCExpression> typeArgs = new ListBuffer<JCExpression>();
+		for (JCTypeParameter typeParam : typeParams) typeArgs.append(maker.Ident(typeParam.name));
+		
+		JCExpression call = maker.NewClass(null, List.<JCExpression>nil(), namePlusTypeParamsToTypeReference(maker, type.toName(builderImplClassName), typeParams), List.<JCExpression>nil(), null);
+		JCStatement statement = maker.Return(call);
+		
+		JCBlock body = maker.Block(0, List.<JCStatement>of(statement));
+		int modifiers = Flags.PUBLIC;
+		modifiers |= Flags.STATIC;
+		
+		// Add any type params of the annotated class to the return type.
+		ListBuffer<JCExpression> typeParameterNames = new ListBuffer<JCExpression>();
+		typeParameterNames.addAll(typeParameterNames(maker, typeParams));
+		// Now add the <?, ?>.
+		JCWildcard wildcard = maker.Wildcard(maker.TypeBoundKind(BoundKind.UNBOUND), null);
+		typeParameterNames.add(wildcard);
+		typeParameterNames.add(wildcard);
+		JCTypeApply returnType = maker.TypeApply(maker.Ident(type.toName(builderClassName)), typeParameterNames.toList());
+		
+		return maker.MethodDef(maker.Modifiers(modifiers), type.toName(builderMethodName), returnType, copyTypeParams(source, typeParams), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+	}
+	
+	private JCMethodDecl generateAbstractSelfMethod(JavacNode type, boolean override, String builderGenericName) {
+		JavacTreeMaker maker = type.getTreeMaker();
+		List<JCAnnotation> annotations = List.nil();
+		if (override) {
+			JCAnnotation overrideAnnotation = maker.Annotation(genJavaLangTypeRef(type, "Override"), List.<JCExpression>nil());
+			annotations = List.of(overrideAnnotation);
+		}
+		JCModifiers modifiers = maker.Modifiers(Flags.PROTECTED | Flags.ABSTRACT, annotations);
+		Name name = type.toName(SELF_METHOD);
+		JCExpression returnType = maker.Ident(type.toName(builderGenericName));
+		
+		return maker.MethodDef(modifiers, name, returnType, List.<JCTypeParameter>nil(), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), null, null);
+	}
+	
+	private JCMethodDecl generateSelfMethod(JavacNode builderImplType) {
+		JavacTreeMaker maker = builderImplType.getTreeMaker();
+		
+		JCAnnotation overrideAnnotation = maker.Annotation(genJavaLangTypeRef(builderImplType, "Override"), List.<JCExpression>nil());
+		JCModifiers modifiers = maker.Modifiers(Flags.PROTECTED, List.of(overrideAnnotation));
+		Name name = builderImplType.toName(SELF_METHOD);
+		JCExpression returnType = maker.Ident(builderImplType.toName(builderImplType.getName()));
+		
+		JCStatement statement = maker.Return(maker.Ident(builderImplType.toName("this")));
+		JCBlock body = maker.Block(0, List.<JCStatement>of(statement));
+		
+		return maker.MethodDef(modifiers, name, returnType, List.<JCTypeParameter>nil(), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+	}
+	
+	private JCMethodDecl generateAbstractBuildMethod(JavacNode type, String methodName, boolean override, String classGenericName) {
+		JavacTreeMaker maker = type.getTreeMaker();
+		List<JCAnnotation> annotations = List.nil();
+		if (override) {
+			JCAnnotation overrideAnnotation = maker.Annotation(genJavaLangTypeRef(type, "Override"), List.<JCExpression>nil());
+			annotations = List.of(overrideAnnotation);
+		}
+		JCModifiers modifiers = maker.Modifiers(Flags.PUBLIC | Flags.ABSTRACT, annotations);
+		Name name = type.toName(methodName);
+		JCExpression returnType = maker.Ident(type.toName(classGenericName));
+		
+		return maker.MethodDef(modifiers, name, returnType, List.<JCTypeParameter>nil(), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), null, null);
+	}
+
+	private JCMethodDecl generateBuildMethod(String buildName, JCExpression returnType, JavacNode type, List<JCExpression> thrownExceptions) {
+		JavacTreeMaker maker = type.getTreeMaker();
+		
+		JCExpression call;
+		ListBuffer<JCStatement> statements = new ListBuffer<JCStatement>();
+		
+		// Use a constructor that only has this builder as parameter.
+		List<JCExpression> builderArg = List.<JCExpression>of(maker.Ident(type.toName("this")));
+		call = maker.NewClass(null, List.<JCExpression>nil(), returnType, builderArg, null);
+		statements.append(maker.Return(call));
+		
+		JCBlock body = maker.Block(0, statements.toList());
+		
+		JCAnnotation overrideAnnotation = maker.Annotation(genJavaLangTypeRef(type, "Override"), List.<JCExpression>nil());
+		JCModifiers modifiers = maker.Modifiers(Flags.PUBLIC, List.of(overrideAnnotation));
+		
+		return maker.MethodDef(modifiers, type.toName(buildName), returnType, List.<JCTypeParameter>nil(), List.<JCVariableDecl>nil(), thrownExceptions, body, null);
+	}
+	
+	private JCMethodDecl generateCleanMethod(java.util.List<BuilderFieldData> builderFields, JavacNode type, JCTree source) {
+		JavacTreeMaker maker = type.getTreeMaker();
+		ListBuffer<JCStatement> statements = new ListBuffer<JCStatement>();
+		
+		for (BuilderFieldData bfd : builderFields) {
+			if (bfd.singularData != null && bfd.singularData.getSingularizer() != null) {
+				bfd.singularData.getSingularizer().appendCleaningCode(bfd.singularData, type, source, statements);
+			}
+		}
+		
+		statements.append(maker.Exec(maker.Assign(maker.Select(maker.Ident(type.toName("this")), type.toName("$lombokUnclean")), maker.Literal(CTC_BOOLEAN, 0))));
+		JCBlock body = maker.Block(0, statements.toList());
+		return maker.MethodDef(maker.Modifiers(Flags.PUBLIC), type.toName("$lombokClean"), maker.Type(Javac.createVoidType(type.getSymbolTable(), CTC_VOID)), List.<JCTypeParameter>nil(), List.<JCVariableDecl>nil(), List.<JCExpression>nil(), body, null);
+	}
+	
+	private void generateBuilderFields(JavacNode builderType, java.util.List<BuilderFieldData> builderFields, JCTree source) {
+		int len = builderFields.size();
+		java.util.List<JavacNode> existing = new ArrayList<JavacNode>();
+		for (JavacNode child : builderType.down()) {
+			if (child.getKind() == Kind.FIELD) existing.add(child);
+		}
+		
+		for (int i = len - 1; i >= 0; i--) {
+			BuilderFieldData bfd = builderFields.get(i);
+			if (bfd.singularData != null && bfd.singularData.getSingularizer() != null) {
+				bfd.createdFields.addAll(bfd.singularData.getSingularizer().generateFields(bfd.singularData, builderType, source));
+			} else {
+				JavacNode field = null, setFlag = null;
+				for (JavacNode exists : existing) {
+					Name n = ((JCVariableDecl) exists.get()).name;
+					if (n.equals(bfd.name)) field = exists;
+					if (n.equals(bfd.nameOfSetFlag)) setFlag = exists;
+				}
+				JavacTreeMaker maker = builderType.getTreeMaker();
+				if (field == null) {
+					JCModifiers mods = maker.Modifiers(Flags.PRIVATE);
+					JCVariableDecl newField = maker.VarDef(mods, bfd.name, cloneType(maker, bfd.type, source, builderType.getContext()), null);
+					field = injectFieldAndMarkGenerated(builderType, newField);
+				}
+				if (setFlag == null && bfd.nameOfSetFlag != null) {
+					JCModifiers mods = maker.Modifiers(Flags.PRIVATE);
+					JCVariableDecl newField = maker.VarDef(mods, bfd.nameOfSetFlag, maker.TypeIdent(CTC_BOOLEAN), null);
+					injectFieldAndMarkGenerated(builderType, newField);
+				}
+				bfd.createdFields.add(field);
+			}
+		}
+	}
+	
+	private void generateSetterMethodsForBuilder(final JavacNode builderType, BuilderFieldData fieldNode, JavacNode source, final String builderGenericName) {
+		boolean deprecate = isFieldDeprecated(fieldNode.originalFieldNode);
+		final JavacTreeMaker maker = builderType.getTreeMaker();
+		ExpressionMaker returnTypeMaker = new ExpressionMaker() { @Override public JCExpression make() {
+			return maker.Ident(builderType.toName(builderGenericName));
+		}};
+		
+		StatementMaker returnStatementMaker = new StatementMaker() { @Override public JCStatement make() {
+			return maker.Return(maker.Apply(List.<JCExpression>nil(), maker.Ident(builderType.toName(SELF_METHOD)), List.<JCExpression>nil()));
+		}};
+		
+		if (fieldNode.singularData == null || fieldNode.singularData.getSingularizer() == null) {
+			generateSimpleSetterMethodForBuilder(builderType, deprecate, fieldNode.createdFields.get(0), fieldNode.nameOfSetFlag, source, true, true, returnTypeMaker.make(), returnStatementMaker.make());
+		} else {
+			fieldNode.singularData.getSingularizer().generateMethods(fieldNode.singularData, deprecate, builderType, source.get(), true, returnTypeMaker, returnStatementMaker);
+		}
+	}
+	
+	private void generateSimpleSetterMethodForBuilder(JavacNode builderType, boolean deprecate, JavacNode fieldNode, Name nameOfSetFlag, JavacNode source, boolean fluent, boolean chain, JCExpression returnType, JCStatement returnStatement) {
+		Name fieldName = ((JCVariableDecl) fieldNode.get()).name;
+		
+		for (JavacNode child : builderType.down()) {
+			if (child.getKind() != Kind.METHOD) continue;
+			JCMethodDecl methodDecl = (JCMethodDecl) child.get();
+			Name existingName = methodDecl.name;
+			if (existingName.equals(fieldName) && !isTolerate(fieldNode, methodDecl)) return;
+		}
+		
+		String setterName = fluent ? fieldNode.getName() : HandlerUtil.buildAccessorName("set", fieldNode.getName());
+		
+		JavacTreeMaker maker = fieldNode.getTreeMaker();
+		
+		JCMethodDecl newMethod = HandleSetter.createSetter(Flags.PUBLIC, deprecate, fieldNode, maker, setterName, nameOfSetFlag, returnType, returnStatement, source, List.<JCAnnotation>nil(), List.<JCAnnotation>nil());
+		
+		injectMethod(builderType, newMethod);
+	}
+	
+	private void addObtainVia(BuilderFieldData bfd, JavacNode node) {
+		for (JavacNode child : node.down()) {
+			if (!annotationTypeMatches(ObtainVia.class, child)) continue;
+			AnnotationValues<ObtainVia> ann = createAnnotation(ObtainVia.class, child);
+			bfd.obtainVia = ann.getInstance();
+			bfd.obtainViaNode = child;
+			deleteAnnotationIfNeccessary(child, ObtainVia.class);
+			return;
+		}
+	}
+	
+	/**
+	 * Returns the explicitly requested singular annotation on this node (field
+	 * or parameter), or null if there's no {@code @Singular} annotation on it.
+	 *
+	 * @param node The node (field or method param) to inspect for its name and potential {@code @Singular} annotation.
+	 */
+	private SingularData getSingularData(JavacNode node) {
+		for (JavacNode child : node.down()) {
+			if (!annotationTypeMatches(Singular.class, child)) continue;
+			Name pluralName = node.getKind() == Kind.FIELD ? removePrefixFromField(node) : ((JCVariableDecl) node.get()).name;
+			AnnotationValues<Singular> ann = createAnnotation(Singular.class, child);
+			deleteAnnotationIfNeccessary(child, Singular.class);
+			String explicitSingular = ann.getInstance().value();
+			if (explicitSingular.isEmpty()) {
+				if (Boolean.FALSE.equals(node.getAst().readConfiguration(ConfigurationKeys.SINGULAR_AUTO))) {
+					node.addError("The singular must be specified explicitly (e.g. @Singular(\"task\")) because auto singularization is disabled.");
+					explicitSingular = pluralName.toString();
+				} else {
+					explicitSingular = autoSingularize(pluralName.toString());
+					if (explicitSingular == null) {
+						node.addError("Can't singularize this name; please specify the singular explicitly (i.e. @Singular(\"sheep\"))");
+						explicitSingular = pluralName.toString();
+					}
+				}
+			}
+			Name singularName = node.toName(explicitSingular);
+			
+			JCExpression type = null;
+			if (node.get() instanceof JCVariableDecl) type = ((JCVariableDecl) node.get()).vartype;
+			
+			String name = null;
+			List<JCExpression> typeArgs = List.nil();
+			if (type instanceof JCTypeApply) {
+				typeArgs = ((JCTypeApply) type).arguments;
+				type = ((JCTypeApply) type).clazz;
+			}
+			
+			name = type.toString();
+			
+			String targetFqn = JavacSingularsRecipes.get().toQualified(name);
+			JavacSingularizer singularizer = JavacSingularsRecipes.get().getSingularizer(targetFqn);
+			if (singularizer == null) {
+				node.addError("Lombok does not know how to create the singular-form builder methods for type '" + name + "'; they won't be generated.");
+				return null;
+			}
+			
+			return new SingularData(child, singularName, pluralName, typeArgs, targetFqn, singularizer);
+		}
+		
+		return null;
+	}
+	
+	private String generateNonclashingNameFor(String classGenericName, java.util.List<String> typeParamStrings) {
+		if (!typeParamStrings.contains(classGenericName)) return classGenericName;
+		int counter = 2;
+		while (typeParamStrings.contains(classGenericName + counter)) counter++;
+		return classGenericName + counter;
+	}
+	
+	private JavacNode findInnerClass(JavacNode parent, String name) {
+		for (JavacNode child : parent.down()) {
+			if (child.getKind() != Kind.TYPE) continue;
+			JCClassDecl td = (JCClassDecl) child.get();
+			if (td.name.contentEquals(name)) return child;
+		}
+		return null;
+	}
+	
+	private ListBuffer<JCExpression> getTypeParamExpressions(List<? extends JCTree> typeParams, JavacTreeMaker maker) {
+		ListBuffer<JCExpression> typeParamsForBuilderParameter = new ListBuffer<JCExpression>();
+		for (JCTree typeParam : typeParams) {
+			if (typeParam instanceof JCTypeParameter) {
+				typeParamsForBuilderParameter.add(maker.Ident(((JCTypeParameter)typeParam).getName()));
+			} else if (typeParam instanceof JCIdent) {
+				typeParamsForBuilderParameter.add(maker.Ident(((JCIdent)typeParam).getName()));
+			}
+		}
+		return typeParamsForBuilderParameter;
+	}
+}
diff --git a/src/core/lombok/javac/handlers/JavacSingularsRecipes.java b/src/core/lombok/javac/handlers/JavacSingularsRecipes.java
index 6a76e1dd..ab8c3a42 100644
--- a/src/core/lombok/javac/handlers/JavacSingularsRecipes.java
+++ b/src/core/lombok/javac/handlers/JavacSingularsRecipes.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015-2017 The Project Lombok Authors.
+ * Copyright (C) 2015-2018 The Project Lombok Authors.
  * 
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -53,6 +53,14 @@ import com.sun.tools.javac.util.ListBuffer;
 import com.sun.tools.javac.util.Name;
 
 public class JavacSingularsRecipes {
+	public interface ExpressionMaker {
+		JCExpression make();
+	}
+	
+	public interface StatementMaker {
+		JCStatement make();
+	}
+	
 	private static final JavacSingularsRecipes INSTANCE = new JavacSingularsRecipes();
 	private final Map<String, JavacSingularizer> singularizers = new HashMap<String, JavacSingularizer>();
 	private final TypeLibrary singularizableTypes = new TypeLibrary();
@@ -194,8 +202,36 @@ public class JavacSingularsRecipes {
 		}
 		
 		public abstract java.util.List<JavacNode> generateFields(SingularData data, JavacNode builderType, JCTree source);
-		public abstract void generateMethods(SingularData data, boolean deprecate, JavacNode builderType, JCTree source, boolean fluent, boolean chain);
-		public abstract void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName);
+		
+		/**
+		 * Generates the singular, plural, and clear methods for the given {@link SingularData}.
+		 * Uses the given {@code builderType} as return type if {@code chain == true}, {@code void} otherwise.
+		 * If you need more control over the return type and value, use
+		 * {@link #generateMethods(SingularData, boolean, JavacNode, JCTree, boolean, ExpressionMaker, StatementMaker)}.
+		 */
+		public void generateMethods(SingularData data, boolean deprecate, final JavacNode builderType, JCTree source, boolean fluent, final boolean chain) {
+			final JavacTreeMaker maker = builderType.getTreeMaker();
+			
+			ExpressionMaker returnTypeMaker = new ExpressionMaker() { @Override public JCExpression make() {
+				return chain ? 
+					cloneSelfType(builderType) : 
+					maker.Type(createVoidType(builderType.getSymbolTable(), CTC_VOID));
+			}};
+			
+			StatementMaker returnStatementMaker = new StatementMaker() { @Override public JCStatement make() {
+				return chain ? maker.Return(maker.Ident(builderType.toName("this"))) : null;
+			}};
+			
+			generateMethods(data, deprecate, builderType, source, fluent, returnTypeMaker, returnStatementMaker);
+		}
+		
+		/**
+		 * Generates the singular, plural, and clear methods for the given {@link SingularData}.
+		 * Uses the given {@code returnTypeMaker} and {@code returnStatementMaker} for the generated methods.
+		 */
+		public abstract void generateMethods(SingularData data, boolean deprecate, JavacNode builderType, JCTree source, boolean fluent, ExpressionMaker returnTypeMaker, StatementMaker returnStatementMaker);
+		
+		public abstract void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName, String builderVariable);
 		
 		public boolean requiresCleaning() {
 			try {
@@ -274,9 +310,9 @@ public class JavacSingularsRecipes {
 			return arguments.toList();
 		}
 		
-		/** Generates 'this.<em>name</em>.size()' as an expression; if nullGuard is true, it's this.name == null ? 0 : this.name.size(). */
-		protected JCExpression getSize(JavacTreeMaker maker, JavacNode builderType, Name name, boolean nullGuard, boolean parens) {
-			Name thisName = builderType.toName("this");
+		/** Generates '<em>builderVariable</em>.<em>name</em>.size()' as an expression; if nullGuard is true, it's this.name == null ? 0 : this.name.size(). */
+		protected JCExpression getSize(JavacTreeMaker maker, JavacNode builderType, Name name, boolean nullGuard, boolean parens, String builderVariable) {
+			Name thisName = builderType.toName(builderVariable);
 			JCExpression fn = maker.Select(maker.Select(maker.Ident(thisName), name), builderType.toName("size"));
 			JCExpression sizeInvoke = maker.Apply(List.<JCExpression>nil(), fn, List.<JCExpression>nil());
 			if (nullGuard) {
diff --git a/src/core/lombok/javac/handlers/singulars/JavacGuavaSingularizer.java b/src/core/lombok/javac/handlers/singulars/JavacGuavaSingularizer.java
index 0ab7da54..ffaf6674 100644
--- a/src/core/lombok/javac/handlers/singulars/JavacGuavaSingularizer.java
+++ b/src/core/lombok/javac/handlers/singulars/JavacGuavaSingularizer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015-2017 The Project Lombok Authors.
+ * Copyright (C) 2015-2018 The Project Lombok Authors.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -32,11 +32,12 @@ import lombok.core.handlers.HandlerUtil;
 import lombok.javac.JavacNode;
 import lombok.javac.JavacTreeMaker;
 import lombok.javac.handlers.JavacHandlerUtil;
+import lombok.javac.handlers.JavacSingularsRecipes.ExpressionMaker;
 import lombok.javac.handlers.JavacSingularsRecipes.JavacSingularizer;
 import lombok.javac.handlers.JavacSingularsRecipes.SingularData;
+import lombok.javac.handlers.JavacSingularsRecipes.StatementMaker;
 
 import com.sun.tools.javac.code.Flags;
-import com.sun.tools.javac.code.Symtab;
 import com.sun.tools.javac.tree.JCTree;
 import com.sun.tools.javac.tree.JCTree.JCBlock;
 import com.sun.tools.javac.tree.JCTree.JCExpression;
@@ -70,20 +71,11 @@ abstract class JavacGuavaSingularizer extends JavacSingularizer {
 		return Collections.singletonList(injectFieldAndMarkGenerated(builderType, buildField));
 	}
 	
-	@Override public void generateMethods(SingularData data, boolean deprecate, JavacNode builderType, JCTree source, boolean fluent, boolean chain) {
+	@Override public void generateMethods(SingularData data, boolean deprecate, JavacNode builderType, JCTree source, boolean fluent, ExpressionMaker returnTypeMaker, StatementMaker returnStatementMaker) {
 		JavacTreeMaker maker = builderType.getTreeMaker();
-		Symtab symbolTable = builderType.getSymbolTable();
-		JCExpression returnType = chain ? cloneSelfType(builderType) : maker.Type(createVoidType(symbolTable, CTC_VOID));
-		JCStatement returnStatement = chain ? maker.Return(maker.Ident(builderType.toName("this"))) : null;
-		generateSingularMethod(deprecate, maker, returnType, returnStatement, data, builderType, source, fluent);
-
-		returnType = chain ? cloneSelfType(builderType) : maker.Type(createVoidType(symbolTable, CTC_VOID));
-		returnStatement = chain ? maker.Return(maker.Ident(builderType.toName("this"))) : null;
-		generatePluralMethod(deprecate, maker, returnType, returnStatement, data, builderType, source, fluent);
-		
-		returnType = chain ? cloneSelfType(builderType) : maker.Type(createVoidType(symbolTable, CTC_VOID));
-		returnStatement = chain ? maker.Return(maker.Ident(builderType.toName("this"))) : null;
-		generateClearMethod(deprecate, maker, returnType, returnStatement, data, builderType, source);
+		generateSingularMethod(deprecate, maker, returnTypeMaker.make(), returnStatementMaker.make(), data, builderType, source, fluent);
+		generatePluralMethod(deprecate, maker, returnTypeMaker.make(), returnStatementMaker.make(), data, builderType, source, fluent);
+		generateClearMethod(deprecate, maker, returnTypeMaker.make(), returnStatementMaker.make(), data, builderType, source);
 	}
 	
 	private void generateClearMethod(boolean deprecate, JavacTreeMaker maker, JCExpression returnType, JCStatement returnStatement, SingularData data, JavacNode builderType, JCTree source) {
@@ -168,7 +160,7 @@ abstract class JavacGuavaSingularizer extends JavacSingularizer {
 		injectMethod(builderType, method);
 	}
 	
-	@Override public void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName) {
+	@Override public void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName, String builderVariable) {
 		JavacTreeMaker maker = builderType.getTreeMaker();
 		List<JCExpression> jceBlank = List.nil();
 		
@@ -185,12 +177,12 @@ abstract class JavacGuavaSingularizer extends JavacSingularizer {
 		
 		JCExpression invokeBuild; {
 			//this.pluralName.build();
-			invokeBuild = maker.Apply(jceBlank, chainDots(builderType, "this", data.getPluralName().toString(), "build"), jceBlank);
+			invokeBuild = maker.Apply(jceBlank, chainDots(builderType, builderVariable, data.getPluralName().toString(), "build"), jceBlank);
 		}
 		
 		JCExpression isNull; {
 			//this.pluralName == null
-			isNull = maker.Binary(CTC_EQUAL, maker.Select(maker.Ident(builderType.toName("this")), data.getPluralName()), maker.Literal(CTC_BOT, null));
+			isNull = maker.Binary(CTC_EQUAL, maker.Select(maker.Ident(builderType.toName(builderVariable)), data.getPluralName()), maker.Literal(CTC_BOT, null));
 		}
 		
 		JCExpression init = maker.Conditional(isNull, empty, invokeBuild); // this.pluralName == null ? ImmutableX.of() : this.pluralName.build()
diff --git a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilListSetSingularizer.java b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilListSetSingularizer.java
index 196ce45d..39e53ebb 100644
--- a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilListSetSingularizer.java
+++ b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilListSetSingularizer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015-2017 The Project Lombok Authors.
+ * Copyright (C) 2015-2018 The Project Lombok Authors.
  * 
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -30,10 +30,11 @@ import lombok.core.handlers.HandlerUtil;
 import lombok.javac.JavacNode;
 import lombok.javac.JavacTreeMaker;
 import lombok.javac.handlers.JavacHandlerUtil;
+import lombok.javac.handlers.JavacSingularsRecipes.ExpressionMaker;
 import lombok.javac.handlers.JavacSingularsRecipes.SingularData;
+import lombok.javac.handlers.JavacSingularsRecipes.StatementMaker;
 
 import com.sun.tools.javac.code.Flags;
-import com.sun.tools.javac.code.Symtab;
 import com.sun.tools.javac.tree.JCTree;
 import com.sun.tools.javac.tree.JCTree.JCBlock;
 import com.sun.tools.javac.tree.JCTree.JCExpression;
@@ -76,27 +77,16 @@ abstract class JavacJavaUtilListSetSingularizer extends JavacJavaUtilSingularize
 		return Collections.singletonList(injectFieldAndMarkGenerated(builderType, buildField));
 	}
 	
-	@Override public void generateMethods(SingularData data, boolean deprecate, JavacNode builderType, JCTree source, boolean fluent, boolean chain) {
+	@Override public void generateMethods(SingularData data, boolean deprecate, JavacNode builderType, JCTree source, boolean fluent, ExpressionMaker returnTypeMaker, StatementMaker returnStatementMaker) {
 		if (useGuavaInstead(builderType)) {
-			guavaListSetSingularizer.generateMethods(data, deprecate, builderType, source, fluent, chain);
+			guavaListSetSingularizer.generateMethods(data, deprecate, builderType, source, fluent, returnTypeMaker, returnStatementMaker);
 			return;
 		}
 		
 		JavacTreeMaker maker = builderType.getTreeMaker();
-		Symtab symbolTable = builderType.getSymbolTable();
-		Name thisName = builderType.toName("this");
-		
-		JCExpression returnType = chain ? cloneSelfType(builderType) : maker.Type(createVoidType(symbolTable, CTC_VOID));
-		JCStatement returnStatement = chain ? maker.Return(maker.Ident(thisName)) : null;
-		generateSingularMethod(deprecate, maker, returnType, returnStatement, data, builderType, source, fluent);
-		
-		returnType = chain ? cloneSelfType(builderType) : maker.Type(createVoidType(symbolTable, CTC_VOID));
-		returnStatement = chain ? maker.Return(maker.Ident(thisName)) : null;
-		generatePluralMethod(deprecate, maker, returnType, returnStatement, data, builderType, source, fluent);
-		
-		returnType = chain ? cloneSelfType(builderType) : maker.Type(createVoidType(symbolTable, CTC_VOID));
-		returnStatement = chain ? maker.Return(maker.Ident(thisName)) : null;
-		generateClearMethod(deprecate, maker, returnType, returnStatement, data, builderType, source);
+		generateSingularMethod(deprecate, maker, returnTypeMaker.make(), returnStatementMaker.make(), data, builderType, source, fluent);
+		generatePluralMethod(deprecate, maker, returnTypeMaker.make(), returnStatementMaker.make(), data, builderType, source, fluent);
+		generateClearMethod(deprecate, maker, returnTypeMaker.make(), returnStatementMaker.make(), data, builderType, source);
 	}
 	
 	private void generateClearMethod(boolean deprecate, JavacTreeMaker maker, JCExpression returnType, JCStatement returnStatement, SingularData data, JavacNode builderType, JCTree source) {
diff --git a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilListSingularizer.java b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilListSingularizer.java
index 3002a98f..b1375151 100644
--- a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilListSingularizer.java
+++ b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilListSingularizer.java
@@ -46,9 +46,9 @@ public class JavacJavaUtilListSingularizer extends JavacJavaUtilListSetSingulari
 		return LombokImmutableList.of("java.util.List", "java.util.Collection", "java.lang.Iterable");
 	}
 	
-	@Override public void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName) {
+	@Override public void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName, String builderVariable) {
 		if (useGuavaInstead(builderType)) {
-			guavaListSetSingularizer.appendBuildCode(data, builderType, source, statements, targetVariableName);
+			guavaListSetSingularizer.appendBuildCode(data, builderType, source, statements, targetVariableName, builderVariable);
 			return;
 		}
 		
@@ -71,7 +71,7 @@ public class JavacJavaUtilListSingularizer extends JavacJavaUtilListSetSingulari
 			JCStatement assignStat; {
 				// pluralName = java.util.Collections.singletonList(this.pluralName.get(0));
 				JCExpression zeroLiteral = maker.Literal(CTC_INT, 0);
-				JCExpression arg = maker.Apply(jceBlank, chainDots(builderType, "this", data.getPluralName().toString(), "get"), List.of(zeroLiteral));
+				JCExpression arg = maker.Apply(jceBlank, chainDots(builderType, builderVariable, data.getPluralName().toString(), "get"), List.of(zeroLiteral));
 				List<JCExpression> args = List.of(arg);
 				JCExpression invoke = maker.Apply(jceBlank, chainDots(builderType, "java", "util", "Collections", "singletonList"), args);
 				assignStat = maker.Exec(maker.Assign(maker.Ident(data.getPluralName()), invoke));
@@ -82,12 +82,12 @@ public class JavacJavaUtilListSingularizer extends JavacJavaUtilListSetSingulari
 		}
 		
 		/* default: Create with right size, then addAll */ {
-			List<JCStatement> defStats = createListCopy(maker, data, builderType, source);
+			List<JCStatement> defStats = createListCopy(maker, data, builderType, source, builderVariable);
 			JCCase defaultCase = maker.Case(null, defStats);
 			cases.append(defaultCase);
 		}
 		
-		JCStatement switchStat = maker.Switch(getSize(maker,  builderType, data.getPluralName(), true, false), cases.toList());
+		JCStatement switchStat = maker.Switch(getSize(maker,  builderType, data.getPluralName(), true, false, builderVariable), cases.toList());
 		JCExpression localShadowerType = chainDotsString(builderType, data.getTargetFqn());
 		localShadowerType = addTypeArgs(1, false, builderType, localShadowerType, data.getTypeArgs(), source);
 		JCStatement varDefStat = maker.VarDef(maker.Modifiers(0), data.getPluralName(), localShadowerType, null);
@@ -95,9 +95,9 @@ public class JavacJavaUtilListSingularizer extends JavacJavaUtilListSetSingulari
 		statements.append(switchStat);
 	}
 	
-	private List<JCStatement> createListCopy(JavacTreeMaker maker, SingularData data, JavacNode builderType, JCTree source) {
+	private List<JCStatement> createListCopy(JavacTreeMaker maker, SingularData data, JavacNode builderType, JCTree source, String builderVariable) {
 		List<JCExpression> jceBlank = List.nil();
-		Name thisName = builderType.toName("this");
+		Name thisName = builderType.toName(builderVariable);
 		
 		JCExpression argToUnmodifiable; {
 			 // new java.util.ArrayList<Generics>(this.pluralName);
diff --git a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilMapSingularizer.java b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilMapSingularizer.java
index fd699275..34350f40 100644
--- a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilMapSingularizer.java
+++ b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilMapSingularizer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015-2017 The Project Lombok Authors.
+ * Copyright (C) 2015-2018 The Project Lombok Authors.
  * 
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -31,13 +31,14 @@ import lombok.core.handlers.HandlerUtil;
 import lombok.javac.JavacNode;
 import lombok.javac.JavacTreeMaker;
 import lombok.javac.handlers.JavacHandlerUtil;
+import lombok.javac.handlers.JavacSingularsRecipes.ExpressionMaker;
 import lombok.javac.handlers.JavacSingularsRecipes.JavacSingularizer;
 import lombok.javac.handlers.JavacSingularsRecipes.SingularData;
+import lombok.javac.handlers.JavacSingularsRecipes.StatementMaker;
 
 import org.mangosdk.spi.ProviderFor;
 
 import com.sun.tools.javac.code.Flags;
-import com.sun.tools.javac.code.Symtab;
 import com.sun.tools.javac.tree.JCTree;
 import com.sun.tools.javac.tree.JCTree.JCBlock;
 import com.sun.tools.javac.tree.JCTree.JCExpression;
@@ -101,26 +102,16 @@ public class JavacJavaUtilMapSingularizer extends JavacJavaUtilSingularizer {
 		return Arrays.asList(keyFieldNode, valueFieldNode);
 	}
 	
-	@Override public void generateMethods(SingularData data, boolean deprecate, JavacNode builderType, JCTree source, boolean fluent, boolean chain) {
+	@Override public void generateMethods(SingularData data, boolean deprecate, JavacNode builderType, JCTree source, boolean fluent, ExpressionMaker returnTypeMaker, StatementMaker returnStatementMaker) {
 		if (useGuavaInstead(builderType)) {
-			guavaMapSingularizer.generateMethods(data, deprecate, builderType, source, fluent, chain);
+			guavaMapSingularizer.generateMethods(data, deprecate, builderType, source, fluent, returnTypeMaker, returnStatementMaker);
 			return;
 		}
 		
 		JavacTreeMaker maker = builderType.getTreeMaker();
-		Symtab symbolTable = builderType.getSymbolTable();
-		
-		JCExpression returnType = chain ? cloneSelfType(builderType) : maker.Type(createVoidType(symbolTable, CTC_VOID));
-		JCStatement returnStatement = chain ? maker.Return(maker.Ident(builderType.toName("this"))) : null;
-		generateSingularMethod(deprecate, maker, returnType, returnStatement, data, builderType, source, fluent);
-		
-		returnType = chain ? cloneSelfType(builderType) : maker.Type(createVoidType(symbolTable, CTC_VOID));
-		returnStatement = chain ? maker.Return(maker.Ident(builderType.toName("this"))) : null;
-		generatePluralMethod(deprecate, maker, returnType, returnStatement, data, builderType, source, fluent);
-		
-		returnType = chain ? cloneSelfType(builderType) : maker.Type(createVoidType(symbolTable, CTC_VOID));
-		returnStatement = chain ? maker.Return(maker.Ident(builderType.toName("this"))) : null;
-		generateClearMethod(deprecate, maker, returnType, returnStatement, data, builderType, source);
+		generateSingularMethod(deprecate, maker, returnTypeMaker.make(), returnStatementMaker.make(), data, builderType, source, fluent);
+		generatePluralMethod(deprecate, maker, returnTypeMaker.make(), returnStatementMaker.make(), data, builderType, source, fluent);
+		generateClearMethod(deprecate, maker, returnTypeMaker.make(), returnStatementMaker.make(), data, builderType, source);
 	}
 	
 	private void generateClearMethod(boolean deprecate, JavacTreeMaker maker, JCExpression returnType, JCStatement returnStatement, SingularData data, JavacNode builderType, JCTree source) {
@@ -212,18 +203,18 @@ public class JavacJavaUtilMapSingularizer extends JavacJavaUtilSingularizer {
 		injectMethod(builderType, method);
 	}
 	
-	@Override public void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName) {
+	@Override public void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName, String builderVariable) {
 		if (useGuavaInstead(builderType)) {
-			guavaMapSingularizer.appendBuildCode(data, builderType, source, statements, targetVariableName);
+			guavaMapSingularizer.appendBuildCode(data, builderType, source, statements, targetVariableName, builderVariable);
 			return;
 		}
 		
 		JavacTreeMaker maker = builderType.getTreeMaker();
 		
 		if (data.getTargetFqn().equals("java.util.Map")) {
-			statements.appendList(createJavaUtilSetMapInitialCapacitySwitchStatements(maker, data, builderType, true, "emptyMap", "singletonMap", "LinkedHashMap", source));
+			statements.appendList(createJavaUtilSetMapInitialCapacitySwitchStatements(maker, data, builderType, true, "emptyMap", "singletonMap", "LinkedHashMap", source, builderVariable));
 		} else {
-			statements.appendList(createJavaUtilSimpleCreationAndFillStatements(maker, data, builderType, true, true, false, true, "TreeMap", source));
+			statements.appendList(createJavaUtilSimpleCreationAndFillStatements(maker, data, builderType, true, true, false, true, "TreeMap", source, builderVariable));
 		}
 	}
 }
diff --git a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilSetSingularizer.java b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilSetSingularizer.java
index 317233cb..71a36c0e 100644
--- a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilSetSingularizer.java
+++ b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilSetSingularizer.java
@@ -40,18 +40,18 @@ public class JavacJavaUtilSetSingularizer extends JavacJavaUtilListSetSingulariz
 		return LombokImmutableList.of("java.util.Set", "java.util.SortedSet", "java.util.NavigableSet");
 	}
 	
-	@Override public void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName) {
+	@Override public void appendBuildCode(SingularData data, JavacNode builderType, JCTree source, ListBuffer<JCStatement> statements, Name targetVariableName, String builderVariable) {
 		if (useGuavaInstead(builderType)) {
-			guavaListSetSingularizer.appendBuildCode(data, builderType, source, statements, targetVariableName);
+			guavaListSetSingularizer.appendBuildCode(data, builderType, source, statements, targetVariableName, builderVariable);
 			return;
 		}
 		
 		JavacTreeMaker maker = builderType.getTreeMaker();
 		
 		if (data.getTargetFqn().equals("java.util.Set")) {
-			statements.appendList(createJavaUtilSetMapInitialCapacitySwitchStatements(maker, data, builderType, false, "emptySet", "singleton", "LinkedHashSet", source));
+			statements.appendList(createJavaUtilSetMapInitialCapacitySwitchStatements(maker, data, builderType, false, "emptySet", "singleton", "LinkedHashSet", source, builderVariable));
 		} else {
-			statements.appendList(createJavaUtilSimpleCreationAndFillStatements(maker, data, builderType, false, true, false, true, "TreeSet", source));
+			statements.appendList(createJavaUtilSimpleCreationAndFillStatements(maker, data, builderType, false, true, false, true, "TreeSet", source, builderVariable));
 		}
 	}
 }
diff --git a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilSingularizer.java b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilSingularizer.java
index 0589ac34..df521fd8 100644
--- a/src/core/lombok/javac/handlers/singulars/JavacJavaUtilSingularizer.java
+++ b/src/core/lombok/javac/handlers/singulars/JavacJavaUtilSingularizer.java
@@ -46,7 +46,7 @@ abstract class JavacJavaUtilSingularizer extends JavacSingularizer {
 		return Boolean.TRUE.equals(node.getAst().readConfiguration(ConfigurationKeys.SINGULAR_USE_GUAVA));
 	}
 	
-	protected List<JCStatement> createJavaUtilSetMapInitialCapacitySwitchStatements(JavacTreeMaker maker, SingularData data, JavacNode builderType, boolean mapMode, String emptyCollectionMethod, String singletonCollectionMethod, String targetType, JCTree source) {
+	protected List<JCStatement> createJavaUtilSetMapInitialCapacitySwitchStatements(JavacTreeMaker maker, SingularData data, JavacNode builderType, boolean mapMode, String emptyCollectionMethod, String singletonCollectionMethod, String targetType, JCTree source, String builderVariable) {
 		List<JCExpression> jceBlank = List.nil();
 		ListBuffer<JCCase> cases = new ListBuffer<JCCase>();
 		
@@ -66,11 +66,11 @@ abstract class JavacJavaUtilSingularizer extends JavacSingularizer {
 				// !mapMode: pluralName = java.util.Collections.singletonCollectionMethod(this.pluralName.get(0));
 				//  mapMode: pluralName = java.util.Collections.singletonCollectionMethod(this.pluralName$key.get(0), this.pluralName$value.get(0));
 				JCExpression zeroLiteral = maker.Literal(CTC_INT, 0);
-				JCExpression arg = maker.Apply(jceBlank, chainDots(builderType, "this", data.getPluralName() + (mapMode ? "$key" : ""), "get"), List.of(zeroLiteral));
+				JCExpression arg = maker.Apply(jceBlank, chainDots(builderType, builderVariable, data.getPluralName() + (mapMode ? "$key" : ""), "get"), List.of(zeroLiteral));
 				List<JCExpression> args;
 				if (mapMode) {
 					JCExpression zeroLiteralClone = maker.Literal(CTC_INT, 0);
-					JCExpression arg2 = maker.Apply(jceBlank, chainDots(builderType, "this", data.getPluralName() + (mapMode ? "$value" : ""), "get"), List.of(zeroLiteralClone));
+					JCExpression arg2 = maker.Apply(jceBlank, chainDots(builderType, builderVariable, data.getPluralName() + (mapMode ? "$value" : ""), "get"), List.of(zeroLiteralClone));
 					args = List.of(arg, arg2);
 				} else {
 					args = List.of(arg);
@@ -84,12 +84,12 @@ abstract class JavacJavaUtilSingularizer extends JavacSingularizer {
 		}
 		
 		{ // default:
-			List<JCStatement> statements = createJavaUtilSimpleCreationAndFillStatements(maker, data, builderType, mapMode, false, true, emptyCollectionMethod == null, targetType, source);
+			List<JCStatement> statements = createJavaUtilSimpleCreationAndFillStatements(maker, data, builderType, mapMode, false, true, emptyCollectionMethod == null, targetType, source, builderVariable);
 			JCCase defaultCase = maker.Case(null, statements);
 			cases.append(defaultCase);
 		}
 		
-		JCStatement switchStat = maker.Switch(getSize(maker,  builderType, mapMode ? builderType.toName(data.getPluralName() + "$key") : data.getPluralName(), true, false), cases.toList());
+		JCStatement switchStat = maker.Switch(getSize(maker,  builderType, mapMode ? builderType.toName(data.getPluralName() + "$key") : data.getPluralName(), true, false, builderVariable), cases.toList());
 		JCExpression localShadowerType = chainDotsString(builderType, data.getTargetFqn());
 		localShadowerType = addTypeArgs(mapMode ? 2 : 1, false, builderType, localShadowerType, data.getTypeArgs(), source);
 		JCStatement varDefStat = maker.VarDef(maker.Modifiers(0), data.getPluralName(), localShadowerType, null);
@@ -125,9 +125,9 @@ abstract class JavacJavaUtilSingularizer extends JavacSingularizer {
 		return maker.If(cond, thenPart, null);
 	}
 	
-	protected List<JCStatement> createJavaUtilSimpleCreationAndFillStatements(JavacTreeMaker maker, SingularData data, JavacNode builderType, boolean mapMode, boolean defineVar, boolean addInitialCapacityArg, boolean nullGuard, String targetType, JCTree source) {
+	protected List<JCStatement> createJavaUtilSimpleCreationAndFillStatements(JavacTreeMaker maker, SingularData data, JavacNode builderType, boolean mapMode, boolean defineVar, boolean addInitialCapacityArg, boolean nullGuard, String targetType, JCTree source, String builderVariable) {
 		List<JCExpression> jceBlank = List.nil();
-		Name thisName = builderType.toName("this");
+		Name thisName = builderType.toName(builderVariable);
 		
 		JCStatement createStat; {
 			 // pluralName = new java.util.TargetType(initialCap);
@@ -136,10 +136,10 @@ abstract class JavacJavaUtilSingularizer extends JavacSingularizer {
 				Name varName = mapMode ? builderType.toName(data.getPluralName() + "$key") : data.getPluralName();
 				// this.varName.size() < MAX_POWER_OF_2 ? 1 + this.varName.size() + (this.varName.size() - 3) / 3 : Integer.MAX_VALUE;
 				// lessThanCutOff = this.varName.size() < MAX_POWER_OF_2
-				JCExpression lessThanCutoff = maker.Binary(CTC_LESS_THAN, getSize(maker, builderType, varName, nullGuard, true), maker.Literal(CTC_INT, 0x40000000));
+				JCExpression lessThanCutoff = maker.Binary(CTC_LESS_THAN, getSize(maker, builderType, varName, nullGuard, true, builderVariable), maker.Literal(CTC_INT, 0x40000000));
 				JCExpression integerMaxValue = genJavaLangTypeRef(builderType, "Integer", "MAX_VALUE");
-				JCExpression sizeFormulaLeft = maker.Binary(CTC_PLUS, maker.Literal(CTC_INT, 1), getSize(maker, builderType, varName, nullGuard, true));
-				JCExpression sizeFormulaRightLeft = maker.Parens(maker.Binary(CTC_MINUS, getSize(maker, builderType, varName, nullGuard, true), maker.Literal(CTC_INT, 3)));
+				JCExpression sizeFormulaLeft = maker.Binary(CTC_PLUS, maker.Literal(CTC_INT, 1), getSize(maker, builderType, varName, nullGuard, true, builderVariable));
+				JCExpression sizeFormulaRightLeft = maker.Parens(maker.Binary(CTC_MINUS, getSize(maker, builderType, varName, nullGuard, true, builderVariable), maker.Literal(CTC_INT, 3)));
 				JCExpression sizeFormulaRight = maker.Binary(CTC_DIV, sizeFormulaRightLeft, maker.Literal(CTC_INT, 3));
 				JCExpression sizeFormula = maker.Binary(CTC_PLUS, sizeFormulaLeft, sizeFormulaRight);
 				constructorArgs = List.<JCExpression>of(maker.Conditional(lessThanCutoff, sizeFormula, integerMaxValue));
@@ -163,14 +163,14 @@ abstract class JavacJavaUtilSingularizer extends JavacSingularizer {
 				Name ivar = builderType.toName("$i");
 				Name keyVarName = builderType.toName(data.getPluralName() + "$key");
 				JCExpression pluralnameDotPut = maker.Select(maker.Ident(data.getPluralName()), builderType.toName("put"));
-				JCExpression arg1 = maker.Apply(jceBlank, chainDots(builderType, "this", data.getPluralName() + "$key", "get"), List.<JCExpression>of(maker.Ident(ivar)));
-				JCExpression arg2 = maker.Apply(jceBlank, chainDots(builderType, "this", data.getPluralName() + "$value", "get"), List.<JCExpression>of(maker.Ident(ivar)));
+				JCExpression arg1 = maker.Apply(jceBlank, chainDots(builderType, builderVariable, data.getPluralName() + "$key", "get"), List.<JCExpression>of(maker.Ident(ivar)));
+				JCExpression arg2 = maker.Apply(jceBlank, chainDots(builderType, builderVariable, data.getPluralName() + "$value", "get"), List.<JCExpression>of(maker.Ident(ivar)));
 				// [jdk9] We add an unneccessary (V) cast here. Not doing so gives an error in javac (build 9-ea+156-jigsaw-nightly-h6072-20170212):
 				//   error: method put in interface Map<K#2,V#2> cannot be applied to given types;
 				arg2 = maker.TypeCast(createTypeArgs(2, false, builderType, data.getTypeArgs(), source).get(1), arg2);
 				JCStatement putStatement = maker.Exec(maker.Apply(jceBlank, pluralnameDotPut, List.of(arg1, arg2)));
 				JCStatement forInit = maker.VarDef(maker.Modifiers(0), ivar, maker.TypeIdent(CTC_INT), maker.Literal(CTC_INT, 0));
-				JCExpression checkExpr = maker.Binary(CTC_LESS_THAN, maker.Ident(ivar), getSize(maker, builderType, keyVarName, nullGuard, true));
+				JCExpression checkExpr = maker.Binary(CTC_LESS_THAN, maker.Ident(ivar), getSize(maker, builderType, keyVarName, nullGuard, true, builderVariable));
 				JCExpression incrementExpr = maker.Unary(CTC_POSTINC, maker.Ident(ivar));
 				fillStat = maker.ForLoop(List.of(forInit), checkExpr, List.of(maker.Exec(incrementExpr)), putStatement);
 			} else {