NativeSymbol.java revision 1508:a661018d34b8
14Srgrimes/* 21690Sdg * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved. 31690Sdg * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 41690Sdg * 54Srgrimes * This code is free software; you can redistribute it and/or modify it 64Srgrimes * under the terms of the GNU General Public License version 2 only, as 74Srgrimes * published by the Free Software Foundation. Oracle designates this 84Srgrimes * particular file as subject to the "Classpath" exception as provided 94Srgrimes * by Oracle in the LICENSE file that accompanied this code. 104Srgrimes * 114Srgrimes * This code is distributed in the hope that it will be useful, but WITHOUT 124Srgrimes * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 134Srgrimes * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 144Srgrimes * version 2 for more details (a copy is included in the LICENSE file that 154Srgrimes * accompanied this code). 164Srgrimes * 174Srgrimes * You should have received a copy of the GNU General Public License version 184Srgrimes * 2 along with this work; if not, write to the Free Software Foundation, 194Srgrimes * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 204Srgrimes * 214Srgrimes * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 224Srgrimes * or visit www.oracle.com if you need additional information or have any 234Srgrimes * questions. 244Srgrimes */ 254Srgrimes 264Srgrimespackage jdk.nashorn.internal.objects; 274Srgrimes 284Srgrimesimport static jdk.nashorn.internal.runtime.ECMAErrors.typeError; 294Srgrimes 304Srgrimesimport jdk.nashorn.internal.WeakValueCache; 314Srgrimesimport jdk.nashorn.internal.objects.annotations.Attribute; 324Srgrimesimport jdk.nashorn.internal.objects.annotations.Constructor; 334Srgrimesimport jdk.nashorn.internal.objects.annotations.Function; 344Srgrimesimport jdk.nashorn.internal.objects.annotations.ScriptClass; 354Srgrimesimport jdk.nashorn.internal.objects.annotations.Where; 364Srgrimesimport jdk.nashorn.internal.runtime.JSType; 37608Srgrimesimport jdk.nashorn.internal.runtime.PropertyMap; 384Srgrimesimport jdk.nashorn.internal.runtime.ScriptObject; 394Srgrimesimport jdk.nashorn.internal.runtime.ScriptRuntime; 40115683Sobrienimport jdk.nashorn.internal.runtime.Symbol; 41115683Sobrienimport jdk.nashorn.internal.runtime.Undefined; 42115683Sobrien 434Srgrimes/** 441704Sdg * ECMAScript 6 - 19.4 Symbol Objects 454Srgrimes */ 464Srgrimes@ScriptClass("Symbol") 4771257Speterpublic final class NativeSymbol extends ScriptObject { 4831544Sjmg 49147565Speter private final Symbol symbol; 5071785Speter 51147674Speter // initialized by nasgen 52179277Sjb private static PropertyMap $nasgenmap$; 5371257Speter 5432925Seivind /** See ES6 19.4.2.1 */ 5513203Swollman private static WeakValueCache<String, Symbol> globalSymbolRegistry = new WeakValueCache<>(); 561549Srgrimes 5765557Sjasone NativeSymbol(final Symbol symbol, final Global global) { 581549Srgrimes this(symbol, global.getSymbolPrototype(), $nasgenmap$); 591549Srgrimes } 6031564Ssef 61120937Srobert private NativeSymbol(final Symbol symbol, final ScriptObject prototype, final PropertyMap map) { 62131936Smarcel super(prototype, map); 631549Srgrimes this.symbol = symbol; 6465557Sjasone } 6584811Sjhb 6667365Sjhb private static Symbol getSymbolValue(final Object self) { 6731389Sbde if (self instanceof Symbol) { 6831389Sbde return (Symbol) self; 691549Srgrimes } else if (self instanceof NativeSymbol) { 7064294Sps return ((NativeSymbol) self).symbol; 712257Ssos } else { 7234924Sbde throw typeError("not.a.symbol"); 7312662Sdg } 74146799Sjkoshy } 75146799Sjkoshy 76236238Sfabient // ECMA 6 19.4.3.4 Symbol.prototype [ @@toPrimitive ] ( hint ) 77236238Sfabient @Override 78236238Sfabient public Object getDefaultValue(final Class<?> typeHint) { 79146799Sjkoshy // Just return the symbol value. 80155299Swsalamon return symbol; 814Srgrimes } 8212662Sdg 831549Srgrimes /** 841549Srgrimes * ECMA 6 19.4.3.2 Symbol.prototype.toString ( ) 857090Sbde * 861549Srgrimes * @param self self reference 871549Srgrimes * @return localized string for this Number 8812662Sdg */ 894Srgrimes @Function(attributes = Attribute.NOT_ENUMERABLE) 901549Srgrimes public static String toString(final Object self) { 91121986Sjhb return getSymbolValue(self).toString(); 92214630Sjhb } 937090Sbde 9431389Sbde 9531389Sbde /** 9625164Speter * ECMA 6 19.4.3.3 Symbol.prototype.valueOf ( ) 9731389Sbde * 9830275Speter * @param self self reference 99118952Sjhb * @return number value for this Number 1001549Srgrimes */ 1019545Sjoerg @Function(attributes = Attribute.NOT_ENUMERABLE) 10218207Sbde public static Object valueOf(final Object self) { 10318207Sbde return getSymbolValue(self); 1049545Sjoerg } 1059545Sjoerg 106179277Sjb /** 107179277Sjb * ECMA 6 19.4.1.1 Symbol ( [ description ] ) 108179277Sjb * 109179277Sjb * @param newObj is this function invoked with the new operator 110179277Sjb * @param self self reference 111179277Sjb * @param args arguments 112179277Sjb * @return new symbol value 113179277Sjb */ 114179277Sjb @Constructor(arity = 1) 115179277Sjb public static Object constructor(final boolean newObj, final Object self, final Object... args) { 116179277Sjb if (newObj) { 117179277Sjb throw typeError("symbol.as.constructor"); 118179277Sjb } 119179277Sjb final String description = args.length > 0 && args[0] != Undefined.getUndefined() ? 120179277Sjb JSType.toString(args[0]) : ""; 121179277Sjb return new Symbol(description); 122179277Sjb } 123179277Sjb 124211804Srpaulo /** 125211839Srpaulo * ES6 19.4.2.1 Symbol.for ( key ) 126211839Srpaulo * 127211839Srpaulo * @param self self reference 128211839Srpaulo * @param arg the argument 129211839Srpaulo * @return the symbol value 130211839Srpaulo */ 131179277Sjb @Function(name = "for", attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR) 132179277Sjb public synchronized static Object _for(final Object self, final Object arg) { 133165302Skmacy final String name = JSType.toString(arg); 134165302Skmacy return globalSymbolRegistry.getOrCreate(name, Symbol::new); 13511343Sbde } 13692770Salfred 13792770Salfred /** 13892770Salfred * ES6 19.4.2.5 Symbol.keyFor ( sym ) 1394Srgrimes * 14073001Sjake * @param self self reference 14111163Sjulian * @param arg the argument 142227945Srstone * @return the symbol name 14312702Sphk */ 1445603Sbde @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR) 145757Sdg public synchronized static Object keyFor(final Object self, final Object arg) { 1465603Sbde if (!(arg instanceof Symbol)) { 147757Sdg throw typeError("not.a.symbol", ScriptRuntime.safeToString(arg)); 148757Sdg } 1495603Sbde final String name = ((Symbol) arg).getName(); 150757Sdg return globalSymbolRegistry.get(name) == arg ? name : Undefined.getUndefined(); 15172700Sbde } 1525603Sbde} 1531690Sdg