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/*
* 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
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package jdk.nashorn.internal.runtime;
import static jdk.nashorn.internal.codegen.ObjectClassGenerator.DEBUG_FIELDS;
import static jdk.nashorn.internal.codegen.ObjectClassGenerator.OBJECT_FIELDS_ONLY;
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.codegen.ObjectClassGenerator.shouldInstrument;
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.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
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.lookup.MethodHandleFactory;
/**
* 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("replaceMap", Object.class, Object.class, PropertyMap.class, String.class, Class.class, Class.class);
private static final int NOOF_TYPES = getNumberOfAccessorTypes();
private static final DebugLogger LOG = ObjectClassGenerator.getLogger();
/**
* 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
* @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 (!OBJECT_FIELDS_ONLY) {
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
*/
private MethodHandle[] GETTER_CACHE = new MethodHandle[NOOF_TYPES];
/**
* 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 String 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) */
protected final MethodHandle primitiveGetter;
/** Seed setter for the primitive version of this field (in -Dnashorn.fields.dual=true mode) */
protected final MethodHandle primitiveSetter;
/** Seed getter for the Object version of this field */
protected final MethodHandle objectGetter;
/** Seed setter for the Object version of this field */
protected final MethodHandle objectSetter;
/**
* Current type of this object, in object only mode, this is an Object.class. In dual-fields mode
* null means undefined, and primitive types are allowed. The reason a special type is used for
* undefined, is that are no bits left to represent it in primitive types
*/
private Class<?> currentType;
/**
* 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
setCurrentType(property.getCurrentType());
}
/**
* 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 objectGetter
* @param objectSetter
* @param primitiveGetter
* @param primitiveSetter
*/
protected AccessorProperty(
final String 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
*
* @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 String key, final int flags, final int slot, final MethodHandle getter, final MethodHandle setter) {
super(key, flags | (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 (OBJECT_FIELDS_ONLY) {
primitiveGetter = primitiveSetter = null;
} else {
if (getterType == int.class || getterType == long.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;
setCurrentType(OBJECT_FIELDS_ONLY ? Object.class : getterType);
}
/**
* Normal ACCESS PROPERTY constructor given a structure glass.
* 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 String key, final int flags, final Class<?> structure, final int slot) {
super(key, flags, slot);
/*
* 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];
}
initializeType();
}
/**
* 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 String 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
*
* @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 String key, final int flags, final Class<?> structure, final int slot, final Class<?> initialType) {
this(key, flags, structure, slot);
setCurrentType(OBJECT_FIELDS_ONLY ? Object.class : initialType);
}
/**
* 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.getCurrentType() ? new MethodHandle[NOOF_TYPES] : property.GETTER_CACHE;
this.primitiveGetter = property.primitiveGetter;
this.primitiveSetter = property.primitiveSetter;
this.objectGetter = property.objectGetter;
this.objectSetter = property.objectSetter;
setCurrentType(newType);
}
/**
* COPY constructor
*
* @param property source property
*/
protected AccessorProperty(final AccessorProperty property) {
this(property, property.getCurrentType());
}
/**
* 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) {
setCurrentType(JSType.unboxedFieldType(initialValue));
if (initialValue instanceof Integer) {
invokeSetter(owner, ((Integer)initialValue).intValue());
} else if (initialValue instanceof Long) {
invokeSetter(owner, ((Long)initialValue).longValue());
} else if (initialValue instanceof Double) {
invokeSetter(owner, ((Double)initialValue).doubleValue());
} else {
invokeSetter(owner, initialValue);
}
}
/**
* Initialize the type of a property
*/
protected final void initializeType() {
Class<?> initialType = null;
if (OBJECT_FIELDS_ONLY) {
initialType = Object.class;
} else {
if (!canBeUndefined()) { //todo if !canBeUndefined it means that we have an exact initialType
initialType = int.class;
}
if (shouldInstrument(getKey())) {
info(getKey(), canBeUndefined() ? " can be undefined" : " is always defined");
}
}
setCurrentType(initialType);
}
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 long getLongValue(final ScriptObject self, final ScriptObject owner) {
try {
return (long)getGetter(long.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
* @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
* @param self owner
* @param value value
*/
protected final void invokeSetter(final ScriptObject self, final long value) {
try {
getSetter(long.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
* @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
* @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 long 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
public MethodHandle getGetter(final Class<?> type) {
final int i = getAccessorTypeIndex(type);
assert type == int.class ||
type == long.class ||
type == double.class ||
type == Object.class :
"invalid getter type " + type + " for " + getKey();
//all this does is add a return value filter for object fields only
if (GETTER_CACHE[i] == null) {
GETTER_CACHE[i] = debug(
createGetter(
getCurrentType(),
type,
primitiveGetter,
objectGetter,
INVALID_PROGRAM_POINT),
getCurrentType(),
type,
"get");
}
assert GETTER_CACHE[i].type().returnType() == type && GETTER_CACHE[i].type().parameterType(0) == Object.class;
return GETTER_CACHE[i];
}
@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);
}
return debug(
createGetter(
getCurrentType(),
type,
primitiveGetter,
objectGetter,
programPoint),
getCurrentType(),
type,
"get");
}
private MethodHandle getOptimisticPrimitiveGetter(final Class<?> type, final int programPoint) {
final MethodHandle g = getGetter(getCurrentType());
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;
}
// the final three arguments are for debug printout purposes only
@SuppressWarnings("unused")
private static Object replaceMap(final Object sobj, final PropertyMap newMap, final String key, final Class<?> oldType, final Class<?> newType) {
if (DEBUG_FIELDS && shouldInstrument(key)) {
final PropertyMap oldMap = ((ScriptObject)sobj).getMap();
info("Type change for '" + key + "' " + oldType + "=>" + newType);
finest("setting map " + key+ " => " + sobj + " from " + Debug.id(oldMap) + " to " + Debug.id(newMap) + " " + oldMap + " => " + newMap);
}
((ScriptObject)sobj).setMap(newMap);
return sobj;
}
private MethodHandle generateSetter(final Class<?> forType, final Class<?> type) {
MethodHandle mh = createSetter(forType, type, primitiveSetter, objectSetter);
mh = debug(mh, getCurrentType(), type, "set");
return mh;
}
/**
* Is this property of the undefined type?
* @return true if undefined
*/
protected final boolean isUndefined() {
return getCurrentType() == null;
}
@Override
public MethodHandle getSetter(final Class<?> type, final PropertyMap currentMap) {
final int i = getAccessorTypeIndex(type);
final int ci = isUndefined() ? -1 : getAccessorTypeIndex(getCurrentType());
final Class<?> forType = isUndefined() ? type : getCurrentType();
//if we are asking for an object setter, but are still a primitive type, we might try to box it
MethodHandle mh;
if (needsInvalidator(i, ci)) {
final Property newProperty = getWiderProperty(type);
final PropertyMap newMap = getWiderMap(currentMap, newProperty);
final MethodHandle widerSetter = newProperty.getSetter(type, newMap);
final Class<?> ct = getCurrentType();
mh = MH.filterArguments(widerSetter, 0, MH.insertArguments(REPLACE_MAP, 1, newMap, getKey(), ct, type));
if (ct != null && ct.isPrimitive() && !type.isPrimitive()) {
mh = ObjectClassGenerator.createGuardBoxedPrimitiveSetter(ct, generateSetter(ct, ct), mh);
}
} else {
mh = generateSetter(forType, type);
}
assert mh.type().returnType() == void.class;
return mh;
}
@Override
public final boolean canChangeType() {
if (OBJECT_FIELDS_ONLY) {
return false;
}
return getCurrentType() != Object.class && (isConfigurable() || isWritable());
}
private boolean needsInvalidator(final int ti, final int fti) {
return canChangeType() && ti > fti;
}
// for loggers below, don't bother generating potentially expensive string concat
// operations that will be thrown away anyway, if the level isn't finer than ior
// equal to info
private static void finest(final String... strs) {
if (DEBUG_FIELDS && LOG.levelFinerThanOrEqual(Level.INFO)) {
LOG.finest((Object[])strs);
}
}
private static void info(final String... strs) {
if (DEBUG_FIELDS && LOG.levelFinerThanOrEqual(Level.INFO)) {
LOG.info((Object[])strs);
}
}
private MethodHandle debug(final MethodHandle mh, final Class<?> forType, final Class<?> type, final String tag) {
if (DEBUG_FIELDS && LOG.levelFinerThanOrEqual(Level.INFO) && shouldInstrument(getKey())) {
return MethodHandleFactory.addDebugPrintout(
LOG,
Level.INFO,
mh,
tag + " '" + getKey() + "' (property="+ Debug.id(this) + ", slot=" + getSlot() + " " + getClass().getSimpleName() + " forType=" + stripName(forType) + ", type=" + stripName(type) + ')');
}
return mh;
}
@Override
public final void setCurrentType(final Class<?> currentType) {
assert currentType != boolean.class : "no boolean storage support yet - fix this";
this.currentType = currentType;
}
@Override
public Class<?> getCurrentType() {
return currentType;
}
private static MethodHandle findOwnMH(final String name, final Class<?> rtype, final Class<?>... types) {
return MH.findStatic(LOOKUP, AccessorProperty.class, name, MH.type(rtype, types));
}
}