Mercurial > jdk8-mips64-public > nashorn / file revision

 /*

  * 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 java.lang.invoke.MethodHandle;

 import java.lang.invoke.MethodHandles;

 import java.util.concurrent.Callable;

 import jdk.nashorn.internal.codegen.CompilerConstants;

 import jdk.nashorn.internal.lookup.Lookup;

 import jdk.nashorn.internal.runtime.linker.Bootstrap;

 import static jdk.nashorn.internal.codegen.CompilerConstants.staticCall;

 import jdk.nashorn.internal.objects.Global;

 import static jdk.nashorn.internal.runtime.ECMAErrors.typeError;

 import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED;

 /**

  * Property with user defined getters/setters. Actual getter and setter

  * functions are stored in underlying ScriptObject. Only the 'slot' info is

  * stored in the property.

  *

  * The slots here denote either ScriptObject embed field number or spill

  * array index. For spill array index, we use slot value of

  * (index + ScriptObject.embedSize). See also ScriptObject.getEmbedOrSpill

  * method. Negative slot value means that the corresponding getter or setter

  * is null. Note that always two slots are allocated in ScriptObject - but

  * negative (less by 1) slot number is stored for null getter or setter.

  * This is done so that when the property is redefined with a different

  * getter and setter (say, both non-null), we'll have spill slots to store

  * those. When a slot is negative, (-slot - 1) is the embed/spill index.

  */

 public final class UserAccessorProperty extends Property {

     /** User defined getter function slot. */

     private final int getterSlot;

     /** User defined setter function slot. */

     private final int setterSlot;

     /** Getter method handle */

     private final static CompilerConstants.Call USER_ACCESSOR_GETTER = staticCall(MethodHandles.lookup(), UserAccessorProperty.class,

             "userAccessorGetter", Object.class, ScriptObject.class, int.class, Object.class);

     /** Setter method handle */

     private final static CompilerConstants.Call USER_ACCESSOR_SETTER = staticCall(MethodHandles.lookup(), UserAccessorProperty.class,

             "userAccessorSetter", void.class, ScriptObject.class, int.class, String.class, Object.class, Object.class);

     /** Dynamic invoker for getter */

     private static final Object INVOKE_UA_GETTER = new Object();

     private static MethodHandle getINVOKE_UA_GETTER() {

         return Context.getGlobal().getDynamicInvoker(INVOKE_UA_GETTER,

                 new Callable<MethodHandle>() {

                     @Override

                     public MethodHandle call() {

                         return Bootstrap.createDynamicInvoker("dyn:call", Object.class,

                             Object.class, Object.class);

                     }

                 });

     }

     /** Dynamic invoker for setter */

     private static Object INVOKE_UA_SETTER = new Object();

     private static MethodHandle getINVOKE_UA_SETTER() {

         return Context.getGlobal().getDynamicInvoker(INVOKE_UA_SETTER,

                 new Callable<MethodHandle>() {

                     @Override

                     public MethodHandle call() {

                         return Bootstrap.createDynamicInvoker("dyn:call", void.class,

                             Object.class, Object.class, Object.class);

                     }

                 });

     }

     /**

      * Constructor

      *

      * @param key        property key

      * @param flags      property flags

      * @param getterSlot getter slot, starting at first embed

      * @param setterSlot setter slot, starting at first embed

      */

     UserAccessorProperty(final String key, final int flags, final int getterSlot, final int setterSlot) {

         super(key, flags, -1);

         this.getterSlot = getterSlot;

         this.setterSlot = setterSlot;

     }

     private UserAccessorProperty(final UserAccessorProperty property) {

         super(property);

         this.getterSlot = property.getterSlot;

         this.setterSlot = property.setterSlot;

     }

     /**

      * Return getter spill slot for this UserAccessorProperty.

      * @return getter slot

      */

     public int getGetterSlot() {

         return getterSlot;

     }

     /**

      * Return setter spill slot for this UserAccessorProperty.

      * @return setter slot

      */

     public int getSetterSlot() {

         return setterSlot;

     }

     @Override

     protected Property copy() {

         return new UserAccessorProperty(this);

     }

     @Override

     public boolean equals(final Object other) {

         if (!super.equals(other)) {

             return false;

         }

         final UserAccessorProperty uc = (UserAccessorProperty) other;

         return getterSlot == uc.getterSlot && setterSlot == uc.setterSlot;

     }

     @Override

     public int hashCode() {

         return super.hashCode() ^ getterSlot ^ setterSlot;

     }

     /*

      * Accessors.

      */

     @Override

     public int getSpillCount() {

         return 2;

     }

     @Override

     public boolean hasGetterFunction(final ScriptObject obj) {

         return obj.getSpill(getterSlot) != null;

     }

     @Override

     public boolean hasSetterFunction(final ScriptObject obj) {

         return obj.getSpill(setterSlot) != null;

     }

     @Override

     public Object getObjectValue(final ScriptObject self, final ScriptObject owner) {

         return userAccessorGetter(owner, getGetterSlot(), self);

     }

     @Override

     public void setObjectValue(final ScriptObject self, final ScriptObject owner, final Object value, final boolean strict) {

         userAccessorSetter(owner, getSetterSlot(), strict ? getKey() : null, self, value);

     }

     @Override

     public MethodHandle getGetter(final Class<?> type) {

         return Lookup.filterReturnType(USER_ACCESSOR_GETTER.methodHandle(), type);

     }

     @Override

     public ScriptFunction getGetterFunction(final ScriptObject obj) {

         final Object value = obj.getSpill(getterSlot);

         return (value instanceof ScriptFunction) ? (ScriptFunction) value : null;

     }

     @Override

     public MethodHandle getSetter(final Class<?> type, final PropertyMap currentMap) {

         return USER_ACCESSOR_SETTER.methodHandle();

     }

     @Override

     public ScriptFunction getSetterFunction(final ScriptObject obj) {

         final Object value = obj.getSpill(setterSlot);

         return (value instanceof ScriptFunction) ? (ScriptFunction) value : null;

     }

     // User defined getter and setter are always called by "dyn:call". Note that the user

     // getter/setter may be inherited. If so, proto is bound during lookup. In either

     // inherited or self case, slot is also bound during lookup. Actual ScriptFunction

     // to be called is retrieved everytime and applied.

     static Object userAccessorGetter(final ScriptObject proto, final int slot, final Object self) {

         final ScriptObject container = (proto != null) ? proto : (ScriptObject)self;

         final Object       func      = container.getSpill(slot);

         if (func instanceof ScriptFunction) {

             try {

                 return getINVOKE_UA_GETTER().invokeExact(func, self);

             } catch(final Error|RuntimeException t) {

                 throw t;

             } catch(final Throwable t) {

                 throw new RuntimeException(t);

             }

         }

         return UNDEFINED;

     }

     static void userAccessorSetter(final ScriptObject proto, final int slot, final String name, final Object self, final Object value) {

         final ScriptObject container = (proto != null) ? proto : (ScriptObject)self;

         final Object       func      = container.getSpill(slot);

         if (func instanceof ScriptFunction) {

             try {

                 getINVOKE_UA_SETTER().invokeExact(func, self, value);

             } catch(final Error|RuntimeException t) {

                 throw t;

             } catch(final Throwable t) {

                 throw new RuntimeException(t);

             }

         }  else if (name != null) {

             throw typeError("property.has.no.setter", name, ScriptRuntime.safeToString(self));

         }

     }

 }