/*
 * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * questions.
 */

package jdk.nashorn.internal.runtime;

import static jdk.nashorn.internal.codegen.ObjectClassGenerator.PRIMITIVE_FIELD_TYPE;
import static jdk.nashorn.internal.codegen.ObjectClassGenerator.createGetter;
import static jdk.nashorn.internal.codegen.ObjectClassGenerator.createSetter;
import static jdk.nashorn.internal.codegen.ObjectClassGenerator.getFieldCount;
import static jdk.nashorn.internal.codegen.ObjectClassGenerator.getFieldName;
import static jdk.nashorn.internal.lookup.Lookup.MH;
import static jdk.nashorn.internal.lookup.MethodHandleFactory.stripName;
import static jdk.nashorn.internal.runtime.JSType.getAccessorTypeIndex;
import static jdk.nashorn.internal.runtime.JSType.getNumberOfAccessorTypes;
import static jdk.nashorn.internal.runtime.UnwarrantedOptimismException.INVALID_PROGRAM_POINT;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.SwitchPoint;
import java.util.function.Supplier;
import java.util.logging.Level;
import jdk.nashorn.internal.codegen.ObjectClassGenerator;
import jdk.nashorn.internal.codegen.types.Type;
import jdk.nashorn.internal.lookup.Lookup;
import jdk.nashorn.internal.objects.Global;

An AccessorProperty is the most generic property type. An AccessorProperty is
represented as fields in a ScriptObject class.
/**
 * An AccessorProperty is the most generic property type. An AccessorProperty is
 * represented as fields in a ScriptObject class.
 */
public class AccessorProperty extends Property {
    private static final MethodHandles.Lookup LOOKUP = MethodHandles.lookup();

    private static final MethodHandle REPLACE_MAP   = findOwnMH_S("replaceMap", Object.class, Object.class, PropertyMap.class);
    private static final MethodHandle INVALIDATE_SP = findOwnMH_S("invalidateSwitchPoint", Object.class, AccessorProperty.class, Object.class);

    private static final int NOOF_TYPES = getNumberOfAccessorTypes();
    private static final long serialVersionUID = 3371720170182154920L;

    
Properties in different maps for the same structure class will share their field getters and setters. This could
be further extended to other method handles that are looked up in the AccessorProperty constructor, but right now
these are the most frequently retrieved ones, and lookup of method handle natives only registers in the profiler
for them.
/**
     * Properties in different maps for the same structure class will share their field getters and setters. This could
     * be further extended to other method handles that are looked up in the AccessorProperty constructor, but right now
     * these are the most frequently retrieved ones, and lookup of method handle natives only registers in the profiler
     * for them.
     */
    private static ClassValue<Accessors> GETTERS_SETTERS = new ClassValue<Accessors>() {
        @Override
        protected Accessors computeValue(final Class<?> structure) {
            return new Accessors(structure);
        }
    };

    private static class Accessors {
        final MethodHandle[] objectGetters;
        final MethodHandle[] objectSetters;
        final MethodHandle[] primitiveGetters;
        final MethodHandle[] primitiveSetters;

        
Normal
Params:
structure – /**
         * Normal
         * @param structure
         */
        Accessors(final Class<?> structure) {
            final int fieldCount = getFieldCount(structure);
            objectGetters    = new MethodHandle[fieldCount];
            objectSetters    = new MethodHandle[fieldCount];
            primitiveGetters = new MethodHandle[fieldCount];
            primitiveSetters = new MethodHandle[fieldCount];

            for (int i = 0; i < fieldCount; i++) {
                final String fieldName = getFieldName(i, Type.OBJECT);
                final Class<?> typeClass = Type.OBJECT.getTypeClass();
                objectGetters[i] = MH.asType(MH.getter(LOOKUP, structure, fieldName, typeClass), Lookup.GET_OBJECT_TYPE);
                objectSetters[i] = MH.asType(MH.setter(LOOKUP, structure, fieldName, typeClass), Lookup.SET_OBJECT_TYPE);
            }

            if (!StructureLoader.isSingleFieldStructure(structure.getName())) {
                for (int i = 0; i < fieldCount; i++) {
                    final String fieldNamePrimitive = getFieldName(i, PRIMITIVE_FIELD_TYPE);
                    final Class<?> typeClass = PRIMITIVE_FIELD_TYPE.getTypeClass();
                    primitiveGetters[i] = MH.asType(MH.getter(LOOKUP, structure, fieldNamePrimitive, typeClass), Lookup.GET_PRIMITIVE_TYPE);
                    primitiveSetters[i] = MH.asType(MH.setter(LOOKUP, structure, fieldNamePrimitive, typeClass), Lookup.SET_PRIMITIVE_TYPE);
                }
            }
        }
    }

    
Property getter cache
  Note that we can't do the same simple caching for optimistic getters,
  due to the fact that they are bound to a program point, which will
  produce different boun method handles wrapping the same access mechanism
  depending on callsite
/**
     * Property getter cache
     *   Note that we can't do the same simple caching for optimistic getters,
     *   due to the fact that they are bound to a program point, which will
     *   produce different boun method handles wrapping the same access mechanism
     *   depending on callsite
     */
    private transient MethodHandle[] GETTER_CACHE = new MethodHandle[NOOF_TYPES];

    
Create a new accessor property. Factory method used by nasgen generated code.
Params:
key –  Property key.
propertyFlags – Property flags.
getter –  Property get accessor method.
setter –  Property set accessor method.
Returns:
 New AccessorProperty created./**
     * Create a new accessor property. Factory method used by nasgen generated code.
     *
     * @param key           {@link Property} key.
     * @param propertyFlags {@link Property} flags.
     * @param getter        {@link Property} get accessor method.
     * @param setter        {@link Property} set accessor method.
     *
     * @return  New {@link AccessorProperty} created.
     */
    public static AccessorProperty create(final Object key, final int propertyFlags, final MethodHandle getter, final MethodHandle setter) {
        return new AccessorProperty(key, propertyFlags, -1, getter, setter);
    }

    
Seed getter for the primitive version of this field (in -Dnashorn.fields.dual=true mode) /** Seed getter for the primitive version of this field (in -Dnashorn.fields.dual=true mode) */
    transient MethodHandle primitiveGetter;

    
Seed setter for the primitive version of this field (in -Dnashorn.fields.dual=true mode) /** Seed setter for the primitive version of this field (in -Dnashorn.fields.dual=true mode) */
    transient MethodHandle primitiveSetter;

    
Seed getter for the Object version of this field /** Seed getter for the Object version of this field */
    transient MethodHandle objectGetter;

    
Seed setter for the Object version of this field /** Seed setter for the Object version of this field */
    transient MethodHandle objectSetter;

    
Delegate constructor for bound properties. This is used for properties created by ScriptRuntime.mergeScope and the Nashorn Object.bindProperties method. The former is used to add a script's defined globals to the current global scope while still storing them in a JO-prefixed ScriptObject class. 
All properties created by this constructor have the Property.IS_BOUND flag set.
Params:
property –  accessor property to rebind
delegate –  delegate object to rebind receiver to/**
     * Delegate constructor for bound properties. This is used for properties created by
     * {@link ScriptRuntime#mergeScope} and the Nashorn {@code Object.bindProperties} method.
     * The former is used to add a script's defined globals to the current global scope while
     * still storing them in a JO-prefixed ScriptObject class.
     *
     * <p>All properties created by this constructor have the {@link #IS_BOUND} flag set.</p>
     *
     * @param property  accessor property to rebind
     * @param delegate  delegate object to rebind receiver to
     */
    AccessorProperty(final AccessorProperty property, final Object delegate) {
        super(property, property.getFlags() | IS_BOUND);

        this.primitiveGetter = bindTo(property.primitiveGetter, delegate);
        this.primitiveSetter = bindTo(property.primitiveSetter, delegate);
        this.objectGetter    = bindTo(property.objectGetter, delegate);
        this.objectSetter    = bindTo(property.objectSetter, delegate);
        property.GETTER_CACHE = new MethodHandle[NOOF_TYPES];
        // Properties created this way are bound to a delegate
        setType(property.getType());
    }

    
SPILL PROPERTY or USER ACCESSOR PROPERTY abstract constructor
Constructor for spill properties. Array getters and setters will be created on demand.
Params:
key –    the property key
flags –  the property flags
slot –   spill slot
primitiveGetter – primitive getter
primitiveSetter – primitive setter
objectGetter –    object getter
objectSetter –    object setter/**
     * SPILL PROPERTY or USER ACCESSOR PROPERTY abstract constructor
     *
     * Constructor for spill properties. Array getters and setters will be created on demand.
     *
     * @param key    the property key
     * @param flags  the property flags
     * @param slot   spill slot
     * @param primitiveGetter primitive getter
     * @param primitiveSetter primitive setter
     * @param objectGetter    object getter
     * @param objectSetter    object setter
     */
    protected AccessorProperty(
            final Object key,
            final int flags,
            final int slot,
            final MethodHandle primitiveGetter,
            final MethodHandle primitiveSetter,
            final MethodHandle objectGetter,
            final MethodHandle objectSetter) {
        super(key, flags, slot);
        assert getClass() != AccessorProperty.class;
        this.primitiveGetter = primitiveGetter;
        this.primitiveSetter = primitiveSetter;
        this.objectGetter    = objectGetter;
        this.objectSetter    = objectSetter;
        initializeType();
    }

    
NASGEN constructor
Constructor. Similar to the constructor with both primitive getters and setters, the difference
here being that only one getter and setter (setter is optional for non writable fields) is given
to the constructor, and the rest are created from those. Used e.g. by Nasgen classes
Params:
key –    the property key
flags –  the property flags
slot –   the property field number or spill slot
getter – the property getter
setter – the property setter or null if non writable, non configurable/**
     * NASGEN constructor
     *
     * Constructor. Similar to the constructor with both primitive getters and setters, the difference
     * here being that only one getter and setter (setter is optional for non writable fields) is given
     * to the constructor, and the rest are created from those. Used e.g. by Nasgen classes
     *
     * @param key    the property key
     * @param flags  the property flags
     * @param slot   the property field number or spill slot
     * @param getter the property getter
     * @param setter the property setter or null if non writable, non configurable
     */
    private AccessorProperty(final Object key, final int flags, final int slot, final MethodHandle getter, final MethodHandle setter) {
        super(key, flags | IS_BUILTIN | DUAL_FIELDS | (getter.type().returnType().isPrimitive() ? IS_NASGEN_PRIMITIVE : 0), slot);
        assert !isSpill();

        // we don't need to prep the setters these will never be invalidated as this is a nasgen
        // or known type getter/setter. No invalidations will take place

        final Class<?> getterType = getter.type().returnType();
        final Class<?> setterType = setter == null ? null : setter.type().parameterType(1);

        assert setterType == null || setterType == getterType;

        if (getterType == int.class) {
            primitiveGetter = MH.asType(getter, Lookup.GET_PRIMITIVE_TYPE);
            primitiveSetter = setter == null ? null : MH.asType(setter, Lookup.SET_PRIMITIVE_TYPE);
        } else if (getterType == double.class) {
            primitiveGetter = MH.asType(MH.filterReturnValue(getter, ObjectClassGenerator.PACK_DOUBLE), Lookup.GET_PRIMITIVE_TYPE);
            primitiveSetter = setter == null ? null : MH.asType(MH.filterArguments(setter, 1, ObjectClassGenerator.UNPACK_DOUBLE), Lookup.SET_PRIMITIVE_TYPE);
        } else {
            primitiveGetter = primitiveSetter = null;
        }

        assert primitiveGetter == null || primitiveGetter.type() == Lookup.GET_PRIMITIVE_TYPE : primitiveGetter + "!=" + Lookup.GET_PRIMITIVE_TYPE;
        assert primitiveSetter == null || primitiveSetter.type() == Lookup.SET_PRIMITIVE_TYPE : primitiveSetter;

        objectGetter  = getter.type() != Lookup.GET_OBJECT_TYPE ? MH.asType(getter, Lookup.GET_OBJECT_TYPE) : getter;
        objectSetter  = setter != null && setter.type() != Lookup.SET_OBJECT_TYPE ? MH.asType(setter, Lookup.SET_OBJECT_TYPE) : setter;

        setType(getterType);
    }

    
Normal ACCESS PROPERTY constructor given a structure class.
Constructor for dual field AccessorPropertys.
Params:
key –              property key
flags –            property flags
structure –        structure for objects associated with this property
slot –             property field number or spill slot/**
     * Normal ACCESS PROPERTY constructor given a structure class.
     * Constructor for dual field AccessorPropertys.
     *
     * @param key              property key
     * @param flags            property flags
     * @param structure        structure for objects associated with this property
     * @param slot             property field number or spill slot
     */
    public AccessorProperty(final Object key, final int flags, final Class<?> structure, final int slot) {
        super(key, flags, slot);

        initGetterSetter(structure);
        initializeType();
    }

    private void initGetterSetter(final Class<?> structure) {
        final int slot = getSlot();
        /*
         * primitiveGetter and primitiveSetter are only used in dual fields mode. Setting them to null also
         * works in dual field mode, it only means that the property never has a primitive
         * representation.
         */

        if (isParameter() && hasArguments()) {
            //parameters are always stored in an object array, which may or may not be a good idea
            final MethodHandle arguments = MH.getter(LOOKUP, structure, "arguments", ScriptObject.class);
            objectGetter = MH.asType(MH.insertArguments(MH.filterArguments(ScriptObject.GET_ARGUMENT.methodHandle(), 0, arguments), 1, slot), Lookup.GET_OBJECT_TYPE);
            objectSetter = MH.asType(MH.insertArguments(MH.filterArguments(ScriptObject.SET_ARGUMENT.methodHandle(), 0, arguments), 1, slot), Lookup.SET_OBJECT_TYPE);
            primitiveGetter = null;
            primitiveSetter = null;
        } else {
            final Accessors gs = GETTERS_SETTERS.get(structure);
            objectGetter    = gs.objectGetters[slot];
            primitiveGetter = gs.primitiveGetters[slot];
            objectSetter    = gs.objectSetters[slot];
            primitiveSetter = gs.primitiveSetters[slot];
        }

        // Always use dual fields except for single field structures
        assert hasDualFields() != StructureLoader.isSingleFieldStructure(structure.getName());
    }

    
Constructor
Params:
key –          key
flags –        flags
slot –         field slot index
owner –        owner of property
initialValue – initial value to which the property can be set/**
     * Constructor
     *
     * @param key          key
     * @param flags        flags
     * @param slot         field slot index
     * @param owner        owner of property
     * @param initialValue initial value to which the property can be set
     */
    protected AccessorProperty(final Object key, final int flags, final int slot, final ScriptObject owner, final Object initialValue) {
        this(key, flags, owner.getClass(), slot);
        setInitialValue(owner, initialValue);
    }

    
Normal access property constructor that overrides the type
Override the initial type. Used for Object Literals
Params:
key –          key
flags –        flags
structure –    structure to JO subclass
slot –         field slot index
initialType –  initial type of the property/**
     * Normal access property constructor that overrides the type
     * Override the initial type. Used for Object Literals
     *
     * @param key          key
     * @param flags        flags
     * @param structure    structure to JO subclass
     * @param slot         field slot index
     * @param initialType  initial type of the property
     */
    public AccessorProperty(final Object key, final int flags, final Class<?> structure, final int slot, final Class<?> initialType) {
        this(key, flags, structure, slot);
        setType(hasDualFields() ? initialType : Object.class);
    }

    
Copy constructor that may change type and in that case clear the cache. Important to do that before
type change or getters will be created already stale.
Params:
property – property
newType –  new type/**
     * Copy constructor that may change type and in that case clear the cache. Important to do that before
     * type change or getters will be created already stale.
     *
     * @param property property
     * @param newType  new type
     */
    protected AccessorProperty(final AccessorProperty property, final Class<?> newType) {
        super(property, property.getFlags());

        this.GETTER_CACHE    = newType != property.getLocalType() ? new MethodHandle[NOOF_TYPES] : property.GETTER_CACHE;
        this.primitiveGetter = property.primitiveGetter;
        this.primitiveSetter = property.primitiveSetter;
        this.objectGetter    = property.objectGetter;
        this.objectSetter    = property.objectSetter;

        setType(newType);
    }

    
COPY constructor
Params:
property –  source property/**
     * COPY constructor
     *
     * @param property  source property
     */
    protected AccessorProperty(final AccessorProperty property) {
        this(property, property.getLocalType());
    }

    
Set initial value of a script object's property
Params:
owner –        owner
initialValue – initial value/**
     * Set initial value of a script object's property
     * @param owner        owner
     * @param initialValue initial value
     */
    protected final void setInitialValue(final ScriptObject owner, final Object initialValue) {
        setType(hasDualFields() ? JSType.unboxedFieldType(initialValue) : Object.class);
        if (initialValue instanceof Integer) {
            invokeSetter(owner, ((Integer)initialValue).intValue());
        } else if (initialValue instanceof Double) {
            invokeSetter(owner, ((Double)initialValue).doubleValue());
        } else {
            invokeSetter(owner, initialValue);
        }
    }

    
Initialize the type of a property
/**
     * Initialize the type of a property
     */
    protected final void initializeType() {
        setType(!hasDualFields() ? Object.class : null);
    }

    private void readObject(final ObjectInputStream s) throws IOException, ClassNotFoundException {
        s.defaultReadObject();
        // Restore getters array
        GETTER_CACHE = new MethodHandle[NOOF_TYPES];
    }

    private static MethodHandle bindTo(final MethodHandle mh, final Object receiver) {
        if (mh == null) {
            return null;
        }

        return MH.dropArguments(MH.bindTo(mh, receiver), 0, Object.class);
    }

    @Override
    public Property copy() {
        return new AccessorProperty(this);
    }

    @Override
    public Property copy(final Class<?> newType) {
        return new AccessorProperty(this, newType);
    }

    @Override
    public int getIntValue(final ScriptObject self, final ScriptObject owner) {
        try {
            return (int)getGetter(int.class).invokeExact((Object)self);
        } catch (final Error | RuntimeException e) {
            throw e;
        } catch (final Throwable e) {
            throw new RuntimeException(e);
        }
     }

     @Override
     public double getDoubleValue(final ScriptObject self, final ScriptObject owner) {
        try {
            return (double)getGetter(double.class).invokeExact((Object)self);
        } catch (final Error | RuntimeException e) {
            throw e;
        } catch (final Throwable e) {
            throw new RuntimeException(e);
        }
    }

     @Override
     public Object getObjectValue(final ScriptObject self, final ScriptObject owner) {
        try {
            return getGetter(Object.class).invokeExact((Object)self);
        } catch (final Error | RuntimeException e) {
            throw e;
        } catch (final Throwable e) {
            throw new RuntimeException(e);
        }
    }

     
Invoke setter for this property with a value
Params:
self –  owner
value – value/**
      * Invoke setter for this property with a value
      * @param self  owner
      * @param value value
      */
    protected final void invokeSetter(final ScriptObject self, final int value) {
        try {
            getSetter(int.class, self.getMap()).invokeExact((Object)self, value);
        } catch (final Error | RuntimeException e) {
            throw e;
        } catch (final Throwable e) {
            throw new RuntimeException(e);
        }
    }

    
Invoke setter for this property with a value
Params:
self –  owner
value – value/**
     * Invoke setter for this property with a value
     * @param self  owner
     * @param value value
     */
    protected final void invokeSetter(final ScriptObject self, final double value) {
        try {
            getSetter(double.class, self.getMap()).invokeExact((Object)self, value);
        } catch (final Error | RuntimeException e) {
            throw e;
        } catch (final Throwable e) {
            throw new RuntimeException(e);
        }
    }

    
Invoke setter for this property with a value
Params:
self –  owner
value – value/**
     * Invoke setter for this property with a value
     * @param self  owner
     * @param value value
     */
    protected final void invokeSetter(final ScriptObject self, final Object value) {
        try {
            getSetter(Object.class, self.getMap()).invokeExact((Object)self, value);
        } catch (final Error | RuntimeException e) {
            throw e;
        } catch (final Throwable e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void setValue(final ScriptObject self, final ScriptObject owner, final int value, final boolean strict)  {
        assert isConfigurable() || isWritable() : getKey() + " is not writable or configurable";
        invokeSetter(self, value);
    }

    @Override
    public void setValue(final ScriptObject self, final ScriptObject owner, final double value, final boolean strict)  {
        assert isConfigurable() || isWritable() : getKey() + " is not writable or configurable";
        invokeSetter(self, value);
    }

    @Override
    public void setValue(final ScriptObject self, final ScriptObject owner, final Object value, final boolean strict)  {
        //this is sometimes used for bootstrapping, hence no assert. ugly.
        invokeSetter(self, value);
    }

    @Override
    void initMethodHandles(final Class<?> structure) {
        // sanity check for structure class
        if (!ScriptObject.class.isAssignableFrom(structure) || !StructureLoader.isStructureClass(structure.getName())) {
            throw new IllegalArgumentException();
        }
        // this method is overridden in SpillProperty
        assert !isSpill();
        initGetterSetter(structure);
    }

    @Override
    public MethodHandle getGetter(final Class<?> type) {
        final int i = getAccessorTypeIndex(type);

        assert type == int.class ||
                type == double.class ||
                type == Object.class :
                "invalid getter type " + type + " for " + getKey();

        checkUndeclared();

        //all this does is add a return value filter for object fields only
        final MethodHandle[] getterCache = GETTER_CACHE;
        final MethodHandle cachedGetter = getterCache[i];
        final MethodHandle getter;
        if (cachedGetter != null) {
            getter = cachedGetter;
        } else {
            getter = debug(
                createGetter(
                    getLocalType(),
                    type,
                    primitiveGetter,
                    objectGetter,
                    INVALID_PROGRAM_POINT),
                getLocalType(),
                type,
                "get");
            getterCache[i] = getter;
       }
       assert getter.type().returnType() == type && getter.type().parameterType(0) == Object.class;
       return getter;
    }

    @Override
    public MethodHandle getOptimisticGetter(final Class<?> type, final int programPoint) {
        // nasgen generated primitive fields like Math.PI have only one known unchangeable primitive type
        if (objectGetter == null) {
            return getOptimisticPrimitiveGetter(type, programPoint);
        }

        checkUndeclared();

        return debug(
            createGetter(
                getLocalType(),
                type,
                primitiveGetter,
                objectGetter,
                programPoint),
            getLocalType(),
            type,
            "get");
    }

    private MethodHandle getOptimisticPrimitiveGetter(final Class<?> type, final int programPoint) {
        final MethodHandle g = getGetter(getLocalType());
        return MH.asType(OptimisticReturnFilters.filterOptimisticReturnValue(g, type, programPoint), g.type().changeReturnType(type));
    }

    private Property getWiderProperty(final Class<?> type) {
        return copy(type); //invalidate cache of new property
    }

    private PropertyMap getWiderMap(final PropertyMap oldMap, final Property newProperty) {
        final PropertyMap newMap = oldMap.replaceProperty(this, newProperty);
        assert oldMap.size() > 0;
        assert newMap.size() == oldMap.size();
        return newMap;
    }

    private void checkUndeclared() {
        if ((getFlags() & NEEDS_DECLARATION) != 0) {
            // a lexically defined variable that hasn't seen its declaration - throw ReferenceError
            throw ECMAErrors.referenceError("not.defined", getKey().toString());
        }
    }

    // the final three arguments are for debug printout purposes only
    @SuppressWarnings("unused")
    private static Object replaceMap(final Object sobj, final PropertyMap newMap) {
        ((ScriptObject)sobj).setMap(newMap);
        return sobj;
    }

    @SuppressWarnings("unused")
    private static Object invalidateSwitchPoint(final AccessorProperty property, final Object obj) {
         if (!property.builtinSwitchPoint.hasBeenInvalidated()) {
            SwitchPoint.invalidateAll(new SwitchPoint[] { property.builtinSwitchPoint });
        }
        return obj;
    }

    private MethodHandle generateSetter(final Class<?> forType, final Class<?> type) {
        return debug(createSetter(forType, type, primitiveSetter, objectSetter), getLocalType(), type, "set");
    }

    
Is this property of the undefined type?
Returns:
true if undefined/**
     * Is this property of the undefined type?
     * @return true if undefined
     */
    protected final boolean isUndefined() {
        return getLocalType() == null;
    }

    @Override
    public boolean hasNativeSetter() {
        return objectSetter != null;
    }

    @Override
    public MethodHandle getSetter(final Class<?> type, final PropertyMap currentMap) {
        checkUndeclared();

        final int typeIndex        = getAccessorTypeIndex(type);
        final int currentTypeIndex = getAccessorTypeIndex(getLocalType());

        //if we are asking for an object setter, but are still a primitive type, we might try to box it
        MethodHandle mh;
        if (needsInvalidator(typeIndex, currentTypeIndex)) {
            final Property     newProperty = getWiderProperty(type);
            final PropertyMap  newMap      = getWiderMap(currentMap, newProperty);

            final MethodHandle widerSetter = newProperty.getSetter(type, newMap);
            final Class<?>     ct = getLocalType();
            mh = MH.filterArguments(widerSetter, 0, MH.insertArguments(debugReplace(ct, type, currentMap, newMap) , 1, newMap));
            if (ct != null && ct.isPrimitive() && !type.isPrimitive()) {
                 mh = ObjectClassGenerator.createGuardBoxedPrimitiveSetter(ct, generateSetter(ct, ct), mh);
            }
        } else {
            final Class<?> forType = isUndefined() ? type : getLocalType();
            mh = generateSetter(!forType.isPrimitive() ? Object.class : forType, type);
        }

        if (isBuiltin()) {
           mh = MH.filterArguments(mh, 0, debugInvalidate(MH.insertArguments(INVALIDATE_SP, 0, this), getKey().toString()));
        }

        assert mh.type().returnType() == void.class : mh.type();

        return mh;
    }

    @Override
    public final boolean canChangeType() {
        if (!hasDualFields()) {
            return false;
        }
        // Return true for currently undefined even if non-writable/configurable to allow initialization of ES6 CONST.
        return getLocalType() == null || (getLocalType() != Object.class && (isConfigurable() || isWritable()));
    }

    private boolean needsInvalidator(final int typeIndex, final int currentTypeIndex) {
        return canChangeType() && typeIndex > currentTypeIndex;
    }

    private MethodHandle debug(final MethodHandle mh, final Class<?> forType, final Class<?> type, final String tag) {
        if (!Context.DEBUG || !Global.hasInstance()) {
            return mh;
        }

        final Context context = Context.getContextTrusted();
        assert context != null;

        return context.addLoggingToHandle(
                ObjectClassGenerator.class,
                Level.INFO,
                mh,
                0,
                true,
                new Supplier<String>() {
                    @Override
                    public String get() {
                        return tag + " '" + getKey() + "' (property="+ Debug.id(this) + ", slot=" + getSlot() + " " + getClass().getSimpleName() + " forType=" + stripName(forType) + ", type=" + stripName(type) + ')';
                    }
                });
    }

    private MethodHandle debugReplace(final Class<?> oldType, final Class<?> newType, final PropertyMap oldMap, final PropertyMap newMap) {
        if (!Context.DEBUG || !Global.hasInstance()) {
            return REPLACE_MAP;
        }

        final Context context = Context.getContextTrusted();
        assert context != null;

        MethodHandle mh = context.addLoggingToHandle(
                ObjectClassGenerator.class,
                REPLACE_MAP,
                new Supplier<String>() {
                    @Override
                    public String get() {
                        return "Type change for '" + getKey() + "' " + oldType + "=>" + newType;
                    }
                });

        mh = context.addLoggingToHandle(
                ObjectClassGenerator.class,
                Level.FINEST,
                mh,
                Integer.MAX_VALUE,
                false,
                new Supplier<String>() {
                    @Override
                    public String get() {
                        return "Setting map " + Debug.id(oldMap) + " => " + Debug.id(newMap) + " " + oldMap + " => " + newMap;
                    }
                });
        return mh;
    }

    private static MethodHandle debugInvalidate(final MethodHandle invalidator, final String key) {
        if (!Context.DEBUG || !Global.hasInstance()) {
            return invalidator;
        }

        final Context context = Context.getContextTrusted();
        assert context != null;

        return context.addLoggingToHandle(
                ObjectClassGenerator.class,
                invalidator,
                new Supplier<String>() {
                    @Override
                    public String get() {
                        return "Field change callback for " + key + " triggered ";
                    }
                });
    }

    private static MethodHandle findOwnMH_S(final String name, final Class<?> rtype, final Class<?>... types) {
        return MH.findStatic(LOOKUP, AccessorProperty.class, name, MH.type(rtype, types));
    }
}