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.parser.JSONParser;
37 import jdk.nashorn.internal.parser.TokenType;
38 import jdk.nashorn.internal.runtime.arrays.ArrayIndex;
39 import jdk.nashorn.internal.runtime.linker.Bootstrap;
40
41 /**
42 * Utilities used by "JSON" object implementation.
43 */
44 public final class JSONFunctions {
45 private JSONFunctions() {}
46
47 private static final Object REVIVER_INVOKER = new Object();
48
49 private static MethodHandle getREVIVER_INVOKER() {
50 return ((GlobalObject)Context.getGlobal()).getDynamicInvoker(REVIVER_INVOKER,
51 new Callable<MethodHandle>() {
52 @Override
53 public MethodHandle call() {
54 return Bootstrap.createDynamicInvoker("dyn:call", Object.class,
55 ScriptFunction.class, ScriptObject.class, String.class, Object.class);
56 }
57 });
58 }
59
60 /**
61 * Returns JSON-compatible quoted version of the given string.
62 *
63 * @param str String to be quoted
64 * @return JSON-compatible quoted string
65 */
66 public static String quote(final String str) {
67 return JSONParser.quote(str);
68 }
69
70 /**
71 * Parses the given JSON text string and returns object representation.
72 *
73 * @param text JSON text to be parsed
74 * @param reviver optional value: function that takes two parameters (key, value)
75 * @return Object representation of JSON text given
76 */
77 public static Object parse(final Object text, final Object reviver) {
78 final String str = JSType.toString(text);
79 final JSONParser parser = new JSONParser(
80 new Source("<json>", str),
81 new Context.ThrowErrorManager());
82
83 Node node;
84
85 try {
86 node = parser.parse();
87 } catch (final ParserException e) {
88 throw ECMAErrors.syntaxError(e, "invalid.json", e.getMessage());
89 }
90
91 final ScriptObject global = Context.getGlobalTrusted();
92 Object unfiltered = convertNode(global, node);
93 return applyReviver(global, unfiltered, reviver);
94 }
95
96 // -- Internals only below this point
97
98 // parse helpers
99
100 // apply 'reviver' function if available
101 private static Object applyReviver(final ScriptObject global, final Object unfiltered, final Object reviver) {
102 if (reviver instanceof ScriptFunction) {
103 assert global instanceof GlobalObject;
104 final ScriptObject root = ((GlobalObject)global).newObject();
105 root.addOwnProperty("", Property.WRITABLE_ENUMERABLE_CONFIGURABLE, unfiltered);
106 return walk(root, "", (ScriptFunction)reviver);
107 }
108 return unfiltered;
109 }
110
111 // This is the abstract "Walk" operation from the spec.
112 private static Object walk(final ScriptObject holder, final Object name, final ScriptFunction reviver) {
113 final Object val = holder.get(name);
114 if (val instanceof ScriptObject) {
115 final ScriptObject valueObj = (ScriptObject)val;
116 final Iterator<String> iter = valueObj.propertyIterator();
117
118 while (iter.hasNext()) {
119 final String key = iter.next();
120 final Object newElement = walk(valueObj, key, reviver);
121
122 if (newElement == ScriptRuntime.UNDEFINED) {
123 valueObj.delete(key, false);
124 } else {
125 setPropertyValue(valueObj, key, newElement, false);
126 }
127 }
128 }
129
130 try {
131 // Object.class, ScriptFunction.class, ScriptObject.class, String.class, Object.class);
132 return getREVIVER_INVOKER().invokeExact(reviver, holder, JSType.toString(name), val);
133 } catch(Error|RuntimeException t) {
134 throw t;
135 } catch(final Throwable t) {
136 throw new RuntimeException(t);
137 }
138 }
139
140 // Converts IR node to runtime value
141 private static Object convertNode(final ScriptObject global, final Node node) {
142 assert global instanceof GlobalObject;
143
144 if (node instanceof LiteralNode) {
145 // check for array literal
146 if (node.tokenType() == TokenType.ARRAY) {
147 assert node instanceof LiteralNode.ArrayLiteralNode;
148 final Node[] elements = ((LiteralNode.ArrayLiteralNode)node).getValue();
149
150 // NOTE: We cannot use LiteralNode.isNumericArray() here as that
151 // method uses symbols of element nodes. Since we don't do lower
152 // pass, there won't be any symbols!
153 if (isNumericArray(elements)) {
154 final double[] values = new double[elements.length];
155 int index = 0;
156
157 for (final Node elem : elements) {
158 values[index++] = JSType.toNumber(convertNode(global, elem));
159 }
160 return ((GlobalObject)global).wrapAsObject(values);
161 }
162
163 final Object[] values = new Object[elements.length];
164 int index = 0;
165
166 for (final Node elem : elements) {
167 values[index++] = convertNode(global, elem);
168 }
169
170 return ((GlobalObject)global).wrapAsObject(values);
171 }
172
173 return ((LiteralNode<?>)node).getValue();
174
175 } else if (node instanceof ObjectNode) {
176 final ObjectNode objNode = (ObjectNode) node;
177 final ScriptObject object = ((GlobalObject)global).newObject();
178
179 for (final PropertyNode pNode: objNode.getElements()) {
180 final Node valueNode = pNode.getValue();
181
182 final String name = pNode.getKeyName();
183 final Object value = convertNode(global, valueNode);
184 setPropertyValue(object, name, value, false);
185 }
186
187 return object;
188 } else if (node instanceof UnaryNode) {
189 // UnaryNode used only to represent negative number JSON value
190 final UnaryNode unaryNode = (UnaryNode)node;
191 return -((LiteralNode<?>)unaryNode.rhs()).getNumber();
192 } else {
193 return null;
194 }
195 }
196
197 // add a new property if does not exist already, or else set old property
198 private static void setPropertyValue(final ScriptObject sobj, final String name, final Object value, final boolean strict) {
199 final int index = ArrayIndex.getArrayIndex(name);
200 if (ArrayIndex.isValidArrayIndex(index)) {
201 // array index key
202 sobj.defineOwnProperty(index, value);
203 } else if (sobj.getMap().findProperty(name) != null) {
204 // pre-existing non-inherited property, call set
205 sobj.set(name, value, strict);
206 } else {
207 // add new property
208 sobj.addOwnProperty(name, Property.WRITABLE_ENUMERABLE_CONFIGURABLE, value);
209 }
210 }
211
212 // does the given IR node represent a numeric array?
213 private static boolean isNumericArray(final Node[] values) {
214 for (final Node node : values) {
215 if (node instanceof LiteralNode && ((LiteralNode<?>)node).getValue() instanceof Number) {
216 continue;
217 }
218 return false;
219 }
220 return true;
221 }
222 }