Wither support + tests (javac only; ecj tests are currently set to ignore).

6 files changed, 468 insertions, 95 deletions

diff --git a/src/core/lombok/core/TransformationsUtil.java b/src/core/lombok/core/TransformationsUtil.java
index 69b6b734..921c27d6 100644
--- a/src/core/lombok/core/TransformationsUtil.java
+++ b/src/core/lombok/core/TransformationsUtil.java
@@ -104,20 +104,7 @@ public class TransformationsUtil {
 	 * @return The getter name for this field, or {@code null} if this field does not fit expected patterns and therefore cannot be turned into a getter name.
 	 */
 	public static String toGetterName(AnnotationValues<Accessors> accessors, CharSequence fieldName, boolean isBoolean) {
-		if (fieldName.length() == 0) return null;
-		
-		Accessors ac = accessors.getInstance();
-		fieldName = removePrefix(fieldName, ac.prefix());
-		if (fieldName == null) return null;
-		
-		if (ac.fluent()) return fieldName.toString();
-		
-		if (isBoolean && fieldName.toString().startsWith("is") && fieldName.length() > 2 && !Character.isLowerCase(fieldName.charAt(2))) {
-			// The field is for example named 'isRunning'.
-			return fieldName.toString();
-		}
-		
-		return buildName(isBoolean ? "is" : "get", fieldName.toString());
+		return toAccessorName(accessors, fieldName, isBoolean, "is", "get", true);
 	}
 	
 	/**
@@ -141,20 +128,50 @@ public class TransformationsUtil {
 	 * @return The setter name for this field, or {@code null} if this field does not fit expected patterns and therefore cannot be turned into a getter name.
 	 */
 	public static String toSetterName(AnnotationValues<Accessors> accessors, CharSequence fieldName, boolean isBoolean) {
+		return toAccessorName(accessors, fieldName, isBoolean, "set", "set", true);
+	}
+	
+	/**
+	 * Generates a wither name from a given field name.
+	 * 
+	 * Strategy:
+	 * <ul>
+	 * <li>Reduce the field's name to its base name by stripping off any prefix (from {@code Accessors}). If the field name does not fit
+	 * the prefix list, this method immediately returns {@code null}.</li>
+	 * <li>Only if {@code isBoolean} is true: Check if the field starts with {@code is} followed by a non-lowercase character.
+	 * If so, replace {@code is} with {@code with} and return that.</li> 
+	 * <li>Check if the first character of the field is lowercase. If so, check if the second character
+	 * exists and is title or upper case. If so, uppercase the first character. If not, titlecase the first character.</li>
+	 * <li>Return {@code "with"} plus the possibly title/uppercased first character, and the rest of the field name.</li>
+	 * </ul>
+	 * 
+	 * @param accessors Accessors configuration.
+	 * @param fieldName the name of the field.
+	 * @param isBoolean if the field is of type 'boolean'. For fields of type {@code java.lang.Boolean}, you should provide {@code false}.
+	 * @return The wither name for this field, or {@code null} if this field does not fit expected patterns and therefore cannot be turned into a getter name.
+	 */
+	public static String toWitherName(AnnotationValues<Accessors> accessors, CharSequence fieldName, boolean isBoolean) {
+		return toAccessorName(accessors, fieldName, isBoolean, "with", "with", false);
+	}
+	
+	private static String toAccessorName(AnnotationValues<Accessors> accessors, CharSequence fieldName, boolean isBoolean,
+			String booleanPrefix, String normalPrefix, boolean adhereToFluent) {
+		
 		if (fieldName.length() == 0) return null;
+		
 		Accessors ac = accessors.getInstance();
 		fieldName = removePrefix(fieldName, ac.prefix());
 		if (fieldName == null) return null;
 		
 		String fName = fieldName.toString();
-		if (ac.fluent()) return fName;
+		if (adhereToFluent && ac.fluent()) return fName;
 		
-		if (isBoolean && fName.startsWith("is") && fieldName.length() > 2 && !Character.isLowerCase(fName.charAt(2))) {
+		if (isBoolean && fName.startsWith("is") && fieldName.length() > 2 && !Character.isLowerCase(fieldName.charAt(2))) {
 			// The field is for example named 'isRunning'.
-			return "set" + fName.substring(2);
+			return booleanPrefix + fName.substring(2);
 		}
 		
-		return buildName("set", fName);
+		return buildName(isBoolean ? booleanPrefix : normalPrefix, fName);
 	}
 	
 	/**
@@ -168,28 +185,7 @@ public class TransformationsUtil {
 	 * @param isBoolean if the field is of type 'boolean'. For fields of type 'java.lang.Boolean', you should provide {@code false}.
 	 */
 	public static List<String> toAllGetterNames(AnnotationValues<Accessors> accessors, CharSequence fieldName, boolean isBoolean) {
-		if (!isBoolean) {
-			String getterName = toGetterName(accessors, fieldName, false);
-			return (getterName == null) ? Collections.<String>emptyList() : Collections.singletonList(getterName);
-		}
-		
-		Accessors acc = accessors.getInstance();
-		fieldName = removePrefix(fieldName, acc.prefix());
-		if (fieldName == null) return Collections.emptyList();
-		
-		List<String> baseNames = toBaseNames(fieldName, isBoolean, acc.fluent());
-		
-		Set<String> names = new HashSet<String>();
-		for (String baseName : baseNames) {
-			if (acc.fluent()) {
-				names.add(baseName);
-			} else {
-				names.add(buildName("is", baseName));
-				names.add(buildName("get", baseName));
-			}
-		}
-		
-		return new ArrayList<String>(names);
+		return toAllAccessorNames(accessors, fieldName, isBoolean, "is", "get", true);
 	}
 	
 	/**
@@ -198,13 +194,34 @@ public class TransformationsUtil {
 	 * For example if {@code isBoolean} is true, then a field named {@code isRunning} would produce:<br />
 	 * {@code [setRunning, setIsRunning]}
 	 * 
+	 * @param accessors Accessors configuration.
 	 * @param fieldName the name of the field.
 	 * @param isBoolean if the field is of type 'boolean'. For fields of type 'java.lang.Boolean', you should provide {@code false}.
 	 */
 	public static List<String> toAllSetterNames(AnnotationValues<Accessors> accessors, CharSequence fieldName, boolean isBoolean) {
+		return toAllAccessorNames(accessors, fieldName, isBoolean, "set", "set", true);
+	}
+	
+	/**
+	 * Returns all names of methods that would represent the wither for a field with the provided name.
+	 * 
+	 * For example if {@code isBoolean} is true, then a field named {@code isRunning} would produce:<br />
+	 * {@code [withRunning, withIsRunning]}
+	 * 
+	 * @param accessors Accessors configuration.
+	 * @param fieldName the name of the field.
+	 * @param isBoolean if the field is of type 'boolean'. For fields of type 'java.lang.Boolean', you should provide {@code false}.
+	 */
+	public static List<String> toAllWitherNames(AnnotationValues<Accessors> accessors, CharSequence fieldName, boolean isBoolean) {
+		return toAllAccessorNames(accessors, fieldName, isBoolean, "with", "with", false);
+	}
+	
+	private static List<String> toAllAccessorNames(AnnotationValues<Accessors> accessors, CharSequence fieldName, boolean isBoolean,
+			String booleanPrefix, String normalPrefix, boolean adhereToFluent) {
+		
 		if (!isBoolean) {
-			String setterName = toSetterName(accessors, fieldName, false);
-			return (setterName == null) ? Collections.<String>emptyList() : Collections.singletonList(setterName);
+			String accessorName = toAccessorName(accessors, fieldName, false, booleanPrefix, normalPrefix, adhereToFluent);
+			return (accessorName == null) ? Collections.<String>emptyList() : Collections.singletonList(accessorName);
 		}
 		
 		Accessors acc = accessors.getInstance();
@@ -215,14 +232,16 @@ public class TransformationsUtil {
 		
 		Set<String> names = new HashSet<String>();
 		for (String baseName : baseNames) {
-			if (acc.fluent()) {
+			if (adhereToFluent && acc.fluent()) {
 				names.add(baseName);
 			} else {
-				names.add(buildName("set", baseName));
+				names.add(buildName(normalPrefix, baseName));
+				if (!normalPrefix.equals(booleanPrefix)) names.add(buildName(booleanPrefix, baseName));
 			}
 		}
 		
 		return new ArrayList<String>(names);
+		
 	}
 	
 	private static List<String> toBaseNames(CharSequence fieldName, boolean isBoolean, boolean fluent) {
diff --git a/src/core/lombok/eclipse/handlers/EclipseHandlerUtil.java b/src/core/lombok/eclipse/handlers/EclipseHandlerUtil.java
index 7120a602..f9bb18b1 100644
--- a/src/core/lombok/eclipse/handlers/EclipseHandlerUtil.java
+++ b/src/core/lombok/eclipse/handlers/EclipseHandlerUtil.java
@@ -945,10 +945,7 @@ public class EclipseHandlerUtil {
 	 * Convenient wrapper around {@link TransformationsUtil#toAllGetterNames(lombok.core.AnnotationValues, CharSequence, boolean)}.
 	 */
 	public static List<String> toAllGetterNames(EclipseNode field, boolean isBoolean) {
-		String fieldName = field.getName();
-		AnnotationValues<Accessors> accessors = getAccessorsForField(field);
-		
-		return TransformationsUtil.toAllGetterNames(accessors, fieldName, isBoolean);
+		return TransformationsUtil.toAllGetterNames(getAccessorsForField(field), field.getName(), isBoolean);
 	}
 	
 	/**
@@ -957,10 +954,7 @@ public class EclipseHandlerUtil {
 	 * Convenient wrapper around {@link TransformationsUtil#toGetterName(lombok.core.AnnotationValues, CharSequence, boolean)}.
 	 */
 	public static String toGetterName(EclipseNode field, boolean isBoolean) {
-		String fieldName = field.getName();
-		AnnotationValues<Accessors> accessors = EclipseHandlerUtil.getAccessorsForField(field);
-		
-		return TransformationsUtil.toGetterName(accessors, fieldName, isBoolean);
+		return TransformationsUtil.toGetterName(getAccessorsForField(field), field.getName(), isBoolean);
 	}
 	
 	/**
@@ -968,10 +962,7 @@ public class EclipseHandlerUtil {
 	 * Convenient wrapper around {@link TransformationsUtil#toAllSetterNames(lombok.core.AnnotationValues, CharSequence, boolean)}.
 	 */
 	public static java.util.List<String> toAllSetterNames(EclipseNode field, boolean isBoolean) {
-		String fieldName = field.getName();
-		AnnotationValues<Accessors> accessors = EclipseHandlerUtil.getAccessorsForField(field);
-		
-		return TransformationsUtil.toAllSetterNames(accessors, fieldName, isBoolean);
+		return TransformationsUtil.toAllSetterNames(getAccessorsForField(field), field.getName(), isBoolean);
 	}
 	
 	/**
@@ -980,10 +971,24 @@ public class EclipseHandlerUtil {
 	 * Convenient wrapper around {@link TransformationsUtil#toSetterName(lombok.core.AnnotationValues, CharSequence, boolean)}.
 	 */
 	public static String toSetterName(EclipseNode field, boolean isBoolean) {
-		String fieldName = field.getName();
-		AnnotationValues<Accessors> accessors = EclipseHandlerUtil.getAccessorsForField(field);
-		
-		return TransformationsUtil.toSetterName(accessors, fieldName, isBoolean);
+		return TransformationsUtil.toSetterName(getAccessorsForField(field), field.getName(), isBoolean);
+	}
+	
+	/**
+	 * Translates the given field into all possible wither names.
+	 * Convenient wrapper around {@link TransformationsUtil#toAllWitherNames(lombok.core.AnnotationValues, CharSequence, boolean)}.
+	 */
+	public static java.util.List<String> toAllWitherNames(EclipseNode field, boolean isBoolean) {
+		return TransformationsUtil.toAllWitherNames(getAccessorsForField(field), field.getName(), isBoolean);
+	}
+	
+	/**
+	 * @return the likely wither name for the stated field. (e.g. private boolean foo; to withFoo).
+	 * 
+	 * Convenient wrapper around {@link TransformationsUtil#toWitherName(lombok.core.AnnotationValues, CharSequence, boolean)}.
+	 */
+	public static String toWitherName(EclipseNode field, boolean isBoolean) {
+		return TransformationsUtil.toWitherName(getAccessorsForField(field), field.getName(), isBoolean);
 	}
 	
 	/**
diff --git a/src/core/lombok/experimental/Wither.java b/src/core/lombok/experimental/Wither.java
new file mode 100644
index 00000000..ec2f5496
--- /dev/null
+++ b/src/core/lombok/experimental/Wither.java
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2012 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.experimental;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import lombok.AccessLevel;
+
+/**
+ * Put on any field to make lombok build a 'wither' - a withX method which produces a clone of this object (except for 1 field which gets a new value).
+ * <p>
+ * Example:
+ * <pre>
+ *     private &#64;Wither final int foo;
+ * </pre>
+ * 
+ * will generate:
+ * 
+ * <pre>
+ *     public SELF_TYPE withFoo(int foo) {
+ *         return this.foo == foo ? this : new SELF_TYPE(otherField1, otherField2, foo);
+ *     }
+ * </pre>
+ * 
+ * If any method named {@code withFoo} (case insensitive) exists, regardless of return type or parameters,
+ * no method is generated, and instead a compiler warning is emitted.
+ * <p>
+ * This annotation can also be applied to a class, in which case it'll be as if all non-static fields that don't already have
+ * a {@code Wither} annotation have the annotation.
+ */
+@Target({ElementType.FIELD, ElementType.TYPE})
+@Retention(RetentionPolicy.SOURCE)
+public @interface Wither {
+	/**
+	 * If you want your wither to be non-public, you can specify an alternate access level here.
+	 */
+	AccessLevel value() default AccessLevel.PUBLIC;
+}
diff --git a/src/core/lombok/javac/handlers/HandleSetter.java b/src/core/lombok/javac/handlers/HandleSetter.java
index 02591736..a782e605 100644
--- a/src/core/lombok/javac/handlers/HandleSetter.java
+++ b/src/core/lombok/javac/handlers/HandleSetter.java
@@ -21,8 +21,8 @@
  */
 package lombok.javac.handlers;
 
+import static lombok.javac.Javac.getCtcInt;
 import static lombok.javac.handlers.JavacHandlerUtil.*;
-import static lombok.javac.Javac.*;
 
 import java.util.Collection;
 
@@ -37,6 +37,7 @@ import lombok.core.AnnotationValues;
 import lombok.core.TransformationsUtil;
 import lombok.javac.JavacAnnotationHandler;
 import lombok.javac.JavacNode;
+import lombok.javac.handlers.JavacHandlerUtil.FieldAccess;
 
 import org.mangosdk.spi.ProviderFor;
 
@@ -171,6 +172,11 @@ public class HandleSetter extends JavacAnnotationHandler<Setter> {
 			return;
 		}
 		
+		if ((fieldDecl.mods.flags & Flags.FINAL) != 0) {
+			source.addWarning("Not generating setter for this field: Setters cannot be generated for final fields.");
+			return;
+		}
+		
 		for (String altName : toAllSetterNames(fieldNode)) {
 			switch (methodExists(altName, fieldNode, false, 1)) {
 			case EXISTS_BY_LOMBOK:
@@ -224,20 +230,7 @@ public class HandleSetter extends JavacAnnotationHandler<Setter> {
 		
 		JCExpression methodType = null;
 		if (returnThis) {
-			JavacNode typeNode = field;
-			while (typeNode != null && typeNode.getKind() != Kind.TYPE) typeNode = typeNode.up();
-			if (typeNode != null && typeNode.get() instanceof JCClassDecl) {
-				JCClassDecl type = (JCClassDecl) typeNode.get();
-				ListBuffer<JCExpression> typeArgs = ListBuffer.lb();
-				if (!type.typarams.isEmpty()) {
-					for (JCTypeParameter tp : type.typarams) {
-						typeArgs.append(treeMaker.Ident(tp.name));
-					}
-					methodType = treeMaker.TypeApply(treeMaker.Ident(type.name), typeArgs.toList());
-				} else {
-					methodType = treeMaker.Ident(type.name);
-				}
-			}
+			methodType = cloneSelfType(field);
 		}
 		
 		if (methodType == null) {
diff --git a/src/core/lombok/javac/handlers/HandleWither.java b/src/core/lombok/javac/handlers/HandleWither.java
new file mode 100644
index 00000000..61bf7bd0
--- /dev/null
+++ b/src/core/lombok/javac/handlers/HandleWither.java
@@ -0,0 +1,274 @@
+/*
+ * Copyright (C) 2012 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.javac.Javac.getCtcInt;
+import static lombok.javac.handlers.JavacHandlerUtil.*;
+
+import java.util.Collection;
+
+import lombok.AccessLevel;
+import lombok.core.AST.Kind;
+import lombok.core.AnnotationValues;
+import lombok.core.TransformationsUtil;
+import lombok.experimental.Wither;
+import lombok.javac.JavacAnnotationHandler;
+import lombok.javac.JavacNode;
+import lombok.javac.handlers.JavacHandlerUtil.FieldAccess;
+
+import org.mangosdk.spi.ProviderFor;
+
+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.JCConditional;
+import com.sun.tools.javac.tree.JCTree.JCExpression;
+import com.sun.tools.javac.tree.JCTree.JCMethodDecl;
+import com.sun.tools.javac.tree.JCTree.JCNewClass;
+import com.sun.tools.javac.tree.JCTree.JCReturn;
+import com.sun.tools.javac.tree.JCTree.JCStatement;
+import com.sun.tools.javac.tree.JCTree.JCTypeParameter;
+import com.sun.tools.javac.tree.JCTree.JCVariableDecl;
+import com.sun.tools.javac.tree.TreeMaker;
+import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
+import com.sun.tools.javac.util.List;
+import com.sun.tools.javac.util.ListBuffer;
+import com.sun.tools.javac.util.Name;
+
+/**
+ * Handles the {@code lombok.experimental.Wither} annotation for javac.
+ */
+@ProviderFor(JavacAnnotationHandler.class)
+public class HandleWither extends JavacAnnotationHandler<Wither> {
+	public void generateWitherForType(JavacNode typeNode, JavacNode errorNode, AccessLevel level, boolean checkForTypeLevelWither) {
+		if (checkForTypeLevelWither) {
+			if (typeNode != null) for (JavacNode child : typeNode.down()) {
+				if (child.getKind() == Kind.ANNOTATION) {
+					if (annotationTypeMatches(Wither.class, child)) {
+						//The annotation will make it happen, so we can skip it.
+						return;
+					}
+				}
+			}
+		}
+		
+		JCClassDecl typeDecl = null;
+		if (typeNode.get() instanceof JCClassDecl) typeDecl = (JCClassDecl) typeNode.get();
+		long modifiers = typeDecl == null ? 0 : typeDecl.mods.flags;
+		boolean notAClass = (modifiers & (Flags.INTERFACE | Flags.ANNOTATION | Flags.ENUM)) != 0;
+		
+		if (typeDecl == null || notAClass) {
+			errorNode.addError("@Wither is only supported on a class or a field.");
+			return;
+		}
+		
+		for (JavacNode field : typeNode.down()) {
+			if (field.getKind() != Kind.FIELD) continue;
+			JCVariableDecl fieldDecl = (JCVariableDecl) field.get();
+			//Skip fields that start with $
+			if (fieldDecl.name.toString().startsWith("$")) continue;
+			//Skip static fields.
+			if ((fieldDecl.mods.flags & Flags.STATIC) != 0) continue;
+			//Skip final initialized fields.
+			if ((fieldDecl.mods.flags & Flags.FINAL) != 0 && fieldDecl.init != null) continue;
+			
+			generateWitherForField(field, errorNode.get(), level);
+		}
+	}
+	
+	/**
+	 * Generates a wither on the stated field.
+	 * 
+	 * Used by {@link HandleValue}.
+	 * 
+	 * The difference between this call and the handle method is as follows:
+	 * 
+	 * If there is a {@code lombok.experimental.Wither} annotation on the field, it is used and the
+	 * same rules apply (e.g. warning if the method already exists, stated access level applies).
+	 * If not, the wither is still generated if it isn't already there, though there will not
+	 * be a warning if its already there. The default access level is used.
+	 * 
+	 * @param fieldNode The node representing the field you want a wither for.
+	 * @param pos The node responsible for generating the wither (the {@code @Value} or {@code @Wither} annotation).
+	 */
+	public void generateWitherForField(JavacNode fieldNode, DiagnosticPosition pos, AccessLevel level) {
+		for (JavacNode child : fieldNode.down()) {
+			if (child.getKind() == Kind.ANNOTATION) {
+				if (annotationTypeMatches(Wither.class, child)) {
+					//The annotation will make it happen, so we can skip it.
+					return;
+				}
+			}
+		}
+		
+		createWitherForField(level, fieldNode, fieldNode, false);
+	}
+	
+	@Override public void handle(AnnotationValues<Wither> annotation, JCAnnotation ast, JavacNode annotationNode) {
+		Collection<JavacNode> fields = annotationNode.upFromAnnotationToFields();
+		deleteAnnotationIfNeccessary(annotationNode, Wither.class);
+		deleteImportFromCompilationUnit(annotationNode, "lombok.AccessLevel");
+		JavacNode node = annotationNode.up();
+		AccessLevel level = annotation.getInstance().value();
+		
+		if (level == AccessLevel.NONE || node == null) return;
+		
+		switch (node.getKind()) {
+		case FIELD:
+			createWitherForFields(level, fields, annotationNode, true);
+			break;
+		case TYPE:
+			generateWitherForType(node, annotationNode, level, false);
+			break;
+		}
+	}
+	
+	private void createWitherForFields(AccessLevel level, Collection<JavacNode> fieldNodes, JavacNode errorNode, boolean whineIfExists) {
+		for (JavacNode fieldNode : fieldNodes) {
+			createWitherForField(level, fieldNode, errorNode, whineIfExists);
+		}
+	}
+	
+	private void createWitherForField(AccessLevel level,
+			JavacNode fieldNode, JavacNode source, boolean whineIfExists) {
+		
+		if (fieldNode.getKind() != Kind.FIELD) {
+			fieldNode.addError("@Wither is only supported on a class or a field.");
+			return;
+		}
+		
+		JCVariableDecl fieldDecl = (JCVariableDecl)fieldNode.get();
+		String methodName = toWitherName(fieldNode);
+		
+		if (methodName == null) {
+			source.addWarning("Not generating wither for this field: It does not fit your @Accessors prefix list.");
+			return;
+		}
+		
+		if ((fieldDecl.mods.flags & Flags.STATIC) != 0) {
+			source.addWarning("Not generating wither for this field: Withers cannot be generated for static fields.");
+			return;
+		}
+		
+		if ((fieldDecl.mods.flags & Flags.FINAL) != 0 && fieldDecl.init != null) {
+			source.addWarning("Not generating wither for this field: Withers cannot be generated for final, initialized fields.");
+			return;
+		}
+		
+		if (fieldDecl.name.toString().startsWith("$")) {
+			source.addWarning("Not generating wither for this field: Withers cannot be generated for fields starting with $.");
+			return;
+		}
+		
+		for (String altName : toAllWitherNames(fieldNode)) {
+			switch (methodExists(altName, fieldNode, false, 1)) {
+			case EXISTS_BY_LOMBOK:
+				return;
+			case EXISTS_BY_USER:
+				if (whineIfExists) {
+					String altNameExpl = "";
+					if (!altName.equals(methodName)) altNameExpl = String.format(" (%s)", altName);
+					source.addWarning(
+						String.format("Not generating %s(): A method with that name already exists%s", methodName, altNameExpl));
+				}
+				return;
+			default:
+			case NOT_EXISTS:
+				//continue scanning the other alt names.
+			}
+		}
+		
+		long access = toJavacModifier(level);
+		
+		JCMethodDecl createdWither = createWither(access, fieldNode, fieldNode.getTreeMaker(), source.get());
+		injectMethod(fieldNode.up(), createdWither);
+	}
+	
+	private JCMethodDecl createWither(long access, JavacNode field, TreeMaker treeMaker, JCTree source) {
+		String witherName = toWitherName(field);
+		if (witherName == null) return null;
+		
+		JCVariableDecl fieldDecl = (JCVariableDecl) field.get();
+		
+		ListBuffer<JCStatement> statements = ListBuffer.lb();
+		List<JCAnnotation> nonNulls = findAnnotations(field, TransformationsUtil.NON_NULL_PATTERN);
+		List<JCAnnotation> nullables = findAnnotations(field, TransformationsUtil.NULLABLE_PATTERN);
+		
+		Name methodName = field.toName(witherName);
+		List<JCAnnotation> annsOnParam = nonNulls.appendList(nullables);
+		
+		JCVariableDecl param = treeMaker.VarDef(treeMaker.Modifiers(Flags.FINAL, annsOnParam), fieldDecl.name, fieldDecl.vartype, null);
+		
+		JCExpression selfType = cloneSelfType(field);
+		if (selfType == null) return null;
+		
+		TreeMaker maker = field.getTreeMaker();
+		
+		ListBuffer<JCExpression> args = ListBuffer.lb();
+		for (JavacNode child : field.up().down()) {
+			if (child.getKind() != Kind.FIELD) continue;
+			JCVariableDecl childDecl = (JCVariableDecl) child.get();
+			// Skip fields that start with $
+			if (childDecl.name.toString().startsWith("$")) continue;
+			long fieldFlags = childDecl.mods.flags;
+			// Skip static fields.
+			if ((fieldFlags & Flags.STATIC) != 0) continue;
+			// Skip initialized final fields.
+			if (((fieldFlags & Flags.FINAL) != 0) && childDecl.init != null) continue;
+			if (child.get() == field.get()) {
+				args.append(maker.Ident(fieldDecl.name));
+			} else {
+				args.append(createFieldAccessor(maker, child, FieldAccess.ALWAYS_FIELD));
+			}
+		}
+		
+		JCNewClass newClass = maker.NewClass(null, List.<JCExpression>nil(), selfType, args.toList(), null);
+		JCExpression identityCheck = maker.Binary(getCtcInt(JCTree.class, "EQ"), createFieldAccessor(maker, field, FieldAccess.ALWAYS_FIELD), maker.Ident(fieldDecl.name));
+		JCConditional conditional = maker.Conditional(identityCheck, maker.Ident(field.toName("this")), newClass);
+		JCReturn returnStatement = maker.Return(conditional);
+		
+		if (nonNulls.isEmpty()) {
+			statements.append(returnStatement);
+		} else {
+			JCStatement nullCheck = generateNullCheck(treeMaker, field);
+			if (nullCheck != null) statements.append(nullCheck);
+			statements.append(returnStatement);
+		}
+		
+		JCExpression returnType = cloneSelfType(field);
+		
+		JCBlock methodBody = treeMaker.Block(0, statements.toList());
+		List<JCTypeParameter> methodGenericParams = List.nil();
+		List<JCVariableDecl> parameters = List.of(param);
+		List<JCExpression> throwsClauses = List.nil();
+		JCExpression annotationMethodDefaultValue = null;
+		
+		List<JCAnnotation> annsOnMethod = List.nil();
+		if (isFieldDeprecated(field)) {
+			annsOnMethod = annsOnMethod.prepend(treeMaker.Annotation(chainDots(field, "java", "lang", "Deprecated"), List.<JCExpression>nil()));
+		}
+		return recursiveSetGeneratedBy(treeMaker.MethodDef(treeMaker.Modifiers(access, annsOnMethod), methodName, returnType,
+				methodGenericParams, parameters, throwsClauses, methodBody, annotationMethodDefaultValue), source);
+	}
+}
diff --git a/src/core/lombok/javac/handlers/JavacHandlerUtil.java b/src/core/lombok/javac/handlers/JavacHandlerUtil.java
index 437ba6cb..f2cdee6d 100644
--- a/src/core/lombok/javac/handlers/JavacHandlerUtil.java
+++ b/src/core/lombok/javac/handlers/JavacHandlerUtil.java
@@ -61,6 +61,7 @@ import com.sun.tools.javac.tree.JCTree.JCMethodInvocation;
 import com.sun.tools.javac.tree.JCTree.JCModifiers;
 import com.sun.tools.javac.tree.JCTree.JCNewArray;
 import com.sun.tools.javac.tree.JCTree.JCStatement;
+import com.sun.tools.javac.tree.JCTree.JCTypeParameter;
 import com.sun.tools.javac.tree.JCTree.JCVariableDecl;
 import com.sun.tools.javac.tree.TreeMaker;
 import com.sun.tools.javac.tree.TreeScanner;
@@ -307,11 +308,7 @@ public class JavacHandlerUtil {
 	 * Convenient wrapper around {@link TransformationsUtil#toAllGetterNames(lombok.core.AnnotationValues, CharSequence, boolean)}.
 	 */
 	public static java.util.List<String> toAllGetterNames(JavacNode field) {
-		String fieldName = field.getName();
-		boolean isBoolean = isBoolean(field);
-		AnnotationValues<Accessors> accessors = JavacHandlerUtil.getAccessorsForField(field);
-		
-		return TransformationsUtil.toAllGetterNames(accessors, fieldName, isBoolean);
+		return TransformationsUtil.toAllGetterNames(getAccessorsForField(field), field.getName(), isBoolean(field));
 	}
 	
 	/**
@@ -320,11 +317,7 @@ public class JavacHandlerUtil {
 	 * Convenient wrapper around {@link TransformationsUtil#toGetterName(lombok.core.AnnotationValues, CharSequence, boolean)}.
 	 */
 	public static String toGetterName(JavacNode field) {
-		String fieldName = field.getName();
-		boolean isBoolean = isBoolean(field);
-		AnnotationValues<Accessors> accessors = JavacHandlerUtil.getAccessorsForField(field);
-		
-		return TransformationsUtil.toGetterName(accessors, fieldName, isBoolean);
+		return TransformationsUtil.toGetterName(getAccessorsForField(field), field.getName(), isBoolean(field));
 	}
 	
 	/**
@@ -332,11 +325,7 @@ public class JavacHandlerUtil {
 	 * Convenient wrapper around {@link TransformationsUtil#toAllSetterNames(lombok.core.AnnotationValues, CharSequence, boolean)}.
 	 */
 	public static java.util.List<String> toAllSetterNames(JavacNode field) {
-		String fieldName = field.getName();
-		boolean isBoolean = isBoolean(field);
-		AnnotationValues<Accessors> accessors = JavacHandlerUtil.getAccessorsForField(field);
-		
-		return TransformationsUtil.toAllSetterNames(accessors, fieldName, isBoolean);
+		return TransformationsUtil.toAllSetterNames(getAccessorsForField(field), field.getName(), isBoolean(field));
 	}
 	
 	/**
@@ -345,11 +334,24 @@ public class JavacHandlerUtil {
 	 * Convenient wrapper around {@link TransformationsUtil#toSetterName(lombok.core.AnnotationValues, CharSequence, boolean)}.
 	 */
 	public static String toSetterName(JavacNode field) {
-		String fieldName = field.getName();
-		boolean isBoolean = isBoolean(field);
-		AnnotationValues<Accessors> accessors = JavacHandlerUtil.getAccessorsForField(field);
-		
-		return TransformationsUtil.toSetterName(accessors, fieldName, isBoolean);
+		return TransformationsUtil.toSetterName(getAccessorsForField(field), field.getName(), isBoolean(field));
+	}
+	
+	/**
+	 * Translates the given field into all possible wither names.
+	 * Convenient wrapper around {@link TransformationsUtil#toAllWitherNames(lombok.core.AnnotationValues, CharSequence, boolean)}.
+	 */
+	public static java.util.List<String> toAllWitherNames(JavacNode field) {
+		return TransformationsUtil.toAllWitherNames(getAccessorsForField(field), field.getName(), isBoolean(field));
+	}
+	
+	/**
+	 * @return the likely wither name for the stated field. (e.g. private boolean foo; to withFoo).
+	 * 
+	 * Convenient wrapper around {@link TransformationsUtil#toWitherName(lombok.core.AnnotationValues, CharSequence, boolean)}.
+	 */
+	public static String toWitherName(JavacNode field) {
+		return TransformationsUtil.toWitherName(getAccessorsForField(field), field.getName(), isBoolean(field));
 	}
 	
 	/**
@@ -366,6 +368,26 @@ public class JavacHandlerUtil {
 		return instance.chain() || (instance.fluent() && !forced);
 	}
 	
+	public static JCExpression cloneSelfType(JavacNode field) {
+		JavacNode typeNode = field;
+		TreeMaker maker = field.getTreeMaker();
+		while (typeNode != null && typeNode.getKind() != Kind.TYPE) typeNode = typeNode.up();
+		if (typeNode != null && typeNode.get() instanceof JCClassDecl) {
+			JCClassDecl type = (JCClassDecl) typeNode.get();
+			ListBuffer<JCExpression> typeArgs = ListBuffer.lb();
+			if (!type.typarams.isEmpty()) {
+				for (JCTypeParameter tp : type.typarams) {
+					typeArgs.append(maker.Ident(tp.name));
+				}
+				return maker.TypeApply(maker.Ident(type.name), typeArgs.toList());
+			} else {
+				return maker.Ident(type.name);
+			}
+		} else {
+			return null;
+		}
+	}
+	
 	private static boolean isBoolean(JavacNode field) {
 		JCExpression varType = ((JCVariableDecl) field.get()).vartype;
 		return varType != null && varType.toString().equals("boolean");