1 /*
   2  * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.nashorn.internal.runtime;
  27 
  28 import java.lang.invoke.MethodHandle;
  29 import java.util.ArrayList;
  30 import java.util.Iterator;
  31 import java.util.List;
  32 import java.util.Map;
  33 import java.util.concurrent.Callable;
  34 import jdk.nashorn.internal.codegen.ObjectClassGenerator;
  35 import jdk.nashorn.internal.objects.Global;
  36 import jdk.nashorn.internal.parser.JSONParser;
  37 import jdk.nashorn.internal.runtime.arrays.ArrayData;
  38 import jdk.nashorn.internal.runtime.arrays.ArrayIndex;
  39 import jdk.nashorn.internal.runtime.linker.Bootstrap;
  40 import jdk.nashorn.internal.scripts.JO;
  41 
  42 /**
  43  * Utilities used by "JSON" object implementation.
  44  */
  45 public final class JSONFunctions {
  46     private JSONFunctions() {}
  47 
  48     private static final Object REVIVER_INVOKER = new Object();
  49 
  50     private static MethodHandle getREVIVER_INVOKER() {
  51         return Context.getGlobal().getDynamicInvoker(REVIVER_INVOKER,
  52                 new Callable<MethodHandle>() {
  53                     @Override
  54                     public MethodHandle call() {
  55                         return Bootstrap.createDynamicInvoker("dyn:call", Object.class,
  56                             ScriptFunction.class, ScriptObject.class, String.class, Object.class);
  57                     }
  58                 });
  59     }
  60 
  61     /**
  62      * Returns JSON-compatible quoted version of the given string.
  63      *
  64      * @param str String to be quoted
  65      * @return JSON-compatible quoted string
  66      */
  67     public static String quote(final String str) {
  68         return JSONParser.quote(str);
  69     }
  70 
  71     /**
  72      * Parses the given JSON text string and returns object representation.
  73      *
  74      * @param text JSON text to be parsed
  75      * @param reviver  optional value: function that takes two parameters (key, value)
  76      * @return Object representation of JSON text given
  77      */
  78     public static Object parse(final Object text, final Object reviver) {
  79         final String     str     = JSType.toString(text);
  80         final Global global = Context.getGlobal();
  81         final JSONParser parser  = new JSONParser(str);
  82         final Object value;
  83 
  84         try {
  85             value = parser.parse();
  86         } catch (final ParserException e) {
  87             throw ECMAErrors.syntaxError(e, "invalid.json", e.getMessage());
  88         }
  89 
  90         final Object unfiltered = convert(global, Global.objectPrototype(), value);
  91         return applyReviver(global, unfiltered, reviver);
  92     }
  93 
  94     // -- Internals only below this point
  95 
  96     // parse helpers
  97 
  98     // apply 'reviver' function if available
  99     private static Object applyReviver(final Global global, final Object unfiltered, final Object reviver) {
 100         if (reviver instanceof ScriptFunction) {
 101             final ScriptObject root = global.newObject();
 102             root.addOwnProperty("", Property.WRITABLE_ENUMERABLE_CONFIGURABLE, unfiltered);
 103             return walk(root, "", (ScriptFunction)reviver);
 104         }
 105         return unfiltered;
 106     }
 107 
 108     // This is the abstract "Walk" operation from the spec.
 109     private static Object walk(final ScriptObject holder, final Object name, final ScriptFunction reviver) {
 110         final Object val = holder.get(name);
 111         if (val instanceof ScriptObject) {
 112             final ScriptObject     valueObj = (ScriptObject)val;
 113             final Iterator<String> iter     = valueObj.propertyIterator();
 114 
 115             while (iter.hasNext()) {
 116                 final String key        = iter.next();
 117                 final Object newElement = walk(valueObj, key, reviver);
 118 
 119                 if (newElement == ScriptRuntime.UNDEFINED) {
 120                     valueObj.delete(key, false);
 121                 } else {
 122                     setPropertyValue(valueObj, key, newElement);
 123                 }
 124             }
 125         }
 126 
 127         try {
 128              // Object.class, ScriptFunction.class, ScriptObject.class, String.class, Object.class);
 129              return getREVIVER_INVOKER().invokeExact(reviver, holder, JSType.toString(name), val);
 130         } catch(Error|RuntimeException t) {
 131             throw t;
 132         } catch(final Throwable t) {
 133             throw new RuntimeException(t);
 134         }
 135     }
 136 
 137     // Converts collections to JS objects
 138     @SuppressWarnings("unchecked")
 139     private static Object convert(final Global global, final ScriptObject objectProto, final Object value) {
 140         if (value instanceof Map) {
 141 
 142             final Map<String, Object> map = (Map) value;
 143             final int length = map.size();
 144             final List<Property> properties = new ArrayList<>(length);
 145             final Object[] objectSpill = new Object[length];
 146             final long[] primitiveSpill = new long[length];
 147             ArrayData arrayData = ArrayData.EMPTY_ARRAY;
 148             int slot = 0;
 149 
 150             for (final Map.Entry<String, Object> entry : map.entrySet()) {
 151                 final String name = entry.getKey();
 152                 final Object convertedValue = convert(global, objectProto, entry.getValue());
 153                 final int index = ArrayIndex.getArrayIndex(name);
 154                 if (ArrayIndex.isValidArrayIndex(index)) {
 155                     // array index key
 156                     final long oldLength = arrayData.length();
 157                     final long longIndex = ArrayIndex.toLongIndex(index);
 158                     if (longIndex > oldLength) {
 159                         if (arrayData.canDelete(oldLength, longIndex - 1, false)) {
 160                             arrayData = arrayData.delete(oldLength, longIndex - 1);
 161                         }
 162                     }
 163                     arrayData = arrayData.ensure(longIndex).set(index, convertedValue, false);
 164                 } else {
 165                     // ordinary property key
 166                     final Class<?> type;
 167                     if (ObjectClassGenerator.OBJECT_FIELDS_ONLY) {
 168                         objectSpill[slot] = convertedValue;
 169                         type = Object.class;
 170                     } else {
 171                         type = getType(convertedValue);
 172                         if (type == Object.class) {
 173                             objectSpill[slot] = convertedValue;
 174                         } else {
 175                             primitiveSpill[slot] = ObjectClassGenerator.pack((Number) convertedValue);
 176                         }
 177                     }
 178                     final Property property = new SpillProperty(name, 0, slot++);
 179                     property.setType(type);
 180                     properties.add(property);
 181                 }
 182             }
 183 
 184             final ScriptObject result = new JO(PropertyMap.newMap(properties), primitiveSpill, objectSpill);
 185             result.setInitialProto(objectProto);
 186             result.setArray(arrayData);
 187             return result;
 188 
 189         } else if (value instanceof List) {
 190 
 191             final List<Object> list = (List) value;
 192             if (isNumericArray(list)) {
 193                 final double[] values = new double[list.size()];
 194                 int   index = 0;
 195 
 196                 for (final Object obj : list) {
 197                     values[index++] = JSType.toNumber(obj);
 198                 }
 199                 return global.wrapAsObject(values);
 200             }
 201 
 202             final Object[] values = new Object[list.size()];
 203             int   index = 0;
 204 
 205             for (final Object elem : list) {
 206                 values[index++] = convert(global, objectProto, elem);
 207             }
 208 
 209             return global.wrapAsObject(values);
 210         }
 211 
 212         return value;
 213     }
 214 
 215 
 216     private static Class<?> getType(final Object value) {
 217         if (value instanceof Integer) {
 218             return int.class;
 219         } else if (value instanceof Long) {
 220             return long.class;
 221         } else if (value instanceof Double) {
 222             return double.class;
 223         } else {
 224             return Object.class;
 225         }
 226     }
 227 
 228     // add a new property if does not exist already, or else set old property
 229     private static void setPropertyValue(final ScriptObject sobj, final String name, final Object value) {
 230         final int index = ArrayIndex.getArrayIndex(name);
 231         if (ArrayIndex.isValidArrayIndex(index)) {
 232             // array index key
 233             sobj.defineOwnProperty(index, value);
 234         } else if (sobj.getMap().findProperty(name) != null) {
 235             // pre-existing non-inherited property, call set
 236             sobj.set(name, value, 0);
 237         } else {
 238             // add new property
 239             sobj.addOwnProperty(name, Property.WRITABLE_ENUMERABLE_CONFIGURABLE, value);
 240         }
 241     }
 242 
 243     // does the given list represent a numeric array?
 244     private static boolean isNumericArray(final List<Object> list) {
 245         for (final Object obj : list) {
 246             if (!(obj instanceof Number)) {
 247                 return false;
 248             }
 249         }
 250         return true;
 251     }
 252 }