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.Iterator;
30 import java.util.concurrent.Callable;
31 import jdk.nashorn.internal.ir.LiteralNode;
32 import jdk.nashorn.internal.ir.Node;
33 import jdk.nashorn.internal.ir.ObjectNode;
34 import jdk.nashorn.internal.ir.PropertyNode;
35 import jdk.nashorn.internal.ir.UnaryNode;
36 import jdk.nashorn.internal.objects.Global;
37 import jdk.nashorn.internal.parser.JSONParser;
38 import jdk.nashorn.internal.parser.TokenType;
39 import jdk.nashorn.internal.runtime.arrays.ArrayIndex;
40 import jdk.nashorn.internal.runtime.linker.Bootstrap;
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 JSONParser parser = new JSONParser(
81 new Source("<json>", str),
82 new Context.ThrowErrorManager());
83
84 Node node;
85
86 try {
87 node = parser.parse();
88 } catch (final ParserException e) {
89 throw ECMAErrors.syntaxError(e, "invalid.json", e.getMessage());
90 }
91
92 final Global global = Context.getGlobal();
93 Object unfiltered = convertNode(global, node);
94 return applyReviver(global, unfiltered, reviver);
95 }
96
97 // -- Internals only below this point
98
99 // parse helpers
100
101 // apply 'reviver' function if available
102 private static Object applyReviver(final Global global, final Object unfiltered, final Object reviver) {
103 if (reviver instanceof ScriptFunction) {
104 assert global instanceof Global;
105 final ScriptObject root = global.newObject();
106 root.addOwnProperty("", Property.WRITABLE_ENUMERABLE_CONFIGURABLE, unfiltered);
107 return walk(root, "", (ScriptFunction)reviver);
108 }
109 return unfiltered;
110 }
111
112 // This is the abstract "Walk" operation from the spec.
113 private static Object walk(final ScriptObject holder, final Object name, final ScriptFunction reviver) {
114 final Object val = holder.get(name);
115 if (val instanceof ScriptObject) {
116 final ScriptObject valueObj = (ScriptObject)val;
117 final Iterator<String> iter = valueObj.propertyIterator();
118
119 while (iter.hasNext()) {
120 final String key = iter.next();
121 final Object newElement = walk(valueObj, key, reviver);
122
123 if (newElement == ScriptRuntime.UNDEFINED) {
124 valueObj.delete(key, false);
125 } else {
126 setPropertyValue(valueObj, key, newElement, false);
127 }
128 }
129 }
130
131 try {
132 // Object.class, ScriptFunction.class, ScriptObject.class, String.class, Object.class);
133 return getREVIVER_INVOKER().invokeExact(reviver, holder, JSType.toString(name), val);
134 } catch(Error|RuntimeException t) {
135 throw t;
136 } catch(final Throwable t) {
137 throw new RuntimeException(t);
138 }
139 }
140
141 // Converts IR node to runtime value
142 private static Object convertNode(final Global global, final Node node) {
143 assert global instanceof Global;
144
145 if (node instanceof LiteralNode) {
146 // check for array literal
147 if (node.tokenType() == TokenType.ARRAY) {
148 assert node instanceof LiteralNode.ArrayLiteralNode;
149 final Node[] elements = ((LiteralNode.ArrayLiteralNode)node).getValue();
150
151 // NOTE: We cannot use LiteralNode.isNumericArray() here as that
152 // method uses symbols of element nodes. Since we don't do lower
153 // pass, there won't be any symbols!
154 if (isNumericArray(elements)) {
155 final double[] values = new double[elements.length];
156 int index = 0;
157
158 for (final Node elem : elements) {
159 values[index++] = JSType.toNumber(convertNode(global, elem));
160 }
161 return global.wrapAsObject(values);
162 }
163
164 final Object[] values = new Object[elements.length];
165 int index = 0;
166
167 for (final Node elem : elements) {
168 values[index++] = convertNode(global, elem);
169 }
170
171 return global.wrapAsObject(values);
172 }
173
174 return ((LiteralNode<?>)node).getValue();
175
176 } else if (node instanceof ObjectNode) {
177 final ObjectNode objNode = (ObjectNode) node;
178 final ScriptObject object = global.newObject();
179
180 for (final PropertyNode pNode: objNode.getElements()) {
181 final Node valueNode = pNode.getValue();
182
183 final String name = pNode.getKeyName();
184 final Object value = convertNode(global, valueNode);
185 setPropertyValue(object, name, value, false);
186 }
187
188 return object;
189 } else if (node instanceof UnaryNode) {
190 // UnaryNode used only to represent negative number JSON value
191 final UnaryNode unaryNode = (UnaryNode)node;
192 return -((LiteralNode<?>)unaryNode.rhs()).getNumber();
193 } else {
194 return null;
195 }
196 }
197
198 // add a new property if does not exist already, or else set old property
199 private static void setPropertyValue(final ScriptObject sobj, final String name, final Object value, final boolean strict) {
200 final int index = ArrayIndex.getArrayIndex(name);
201 if (ArrayIndex.isValidArrayIndex(index)) {
202 // array index key
203 sobj.defineOwnProperty(index, value);
204 } else if (sobj.getMap().findProperty(name) != null) {
205 // pre-existing non-inherited property, call set
206 sobj.set(name, value, strict);
207 } else {
208 // add new property
209 sobj.addOwnProperty(name, Property.WRITABLE_ENUMERABLE_CONFIGURABLE, value);
210 }
211 }
212
213 // does the given IR node represent a numeric array?
214 private static boolean isNumericArray(final Node[] values) {
215 for (final Node node : values) {
216 if (node instanceof LiteralNode && ((LiteralNode<?>)node).getValue() instanceof Number) {
217 continue;
218 }
219 return false;
220 }
221 return true;
222 }
223 }