1 /*
2 * Copyright (c) 2010, 2016, 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.linker;
27
28 import static jdk.nashorn.internal.runtime.JSType.isString;
29
30 import java.lang.invoke.MethodHandle;
31 import java.lang.invoke.MethodHandles;
32 import java.lang.invoke.MethodType;
33 import java.util.Map;
34 import javax.script.Bindings;
35 import jdk.dynalink.CallSiteDescriptor;
36 import jdk.dynalink.StandardOperation;
37 import jdk.dynalink.linker.GuardedInvocation;
38 import jdk.dynalink.linker.LinkRequest;
39 import jdk.dynalink.linker.LinkerServices;
40 import jdk.dynalink.linker.TypeBasedGuardingDynamicLinker;
41 import jdk.nashorn.api.scripting.JSObject;
42 import jdk.nashorn.internal.lookup.MethodHandleFactory;
43 import jdk.nashorn.internal.lookup.MethodHandleFunctionality;
44 import jdk.nashorn.internal.runtime.JSType;
45
46 /**
47 * A Dynalink linker to handle web browser built-in JS (DOM etc.) objects as well
48 * as ScriptObjects from other Nashorn contexts.
49 */
50 final class JSObjectLinker implements TypeBasedGuardingDynamicLinker {
51 private final NashornBeansLinker nashornBeansLinker;
52
53 JSObjectLinker(final NashornBeansLinker nashornBeansLinker) {
54 this.nashornBeansLinker = nashornBeansLinker;
55 }
56
57 @Override
58 public boolean canLinkType(final Class<?> type) {
59 return canLinkTypeStatic(type);
60 }
61
62 static boolean canLinkTypeStatic(final Class<?> type) {
63 // can link JSObject also handles Map, Bindings to make
64 // sure those are not JSObjects.
65 return Map.class.isAssignableFrom(type) ||
66 Bindings.class.isAssignableFrom(type) ||
67 JSObject.class.isAssignableFrom(type);
68 }
69
70 @Override
71 public GuardedInvocation getGuardedInvocation(final LinkRequest request, final LinkerServices linkerServices) throws Exception {
72 final Object self = request.getReceiver();
73 final CallSiteDescriptor desc = request.getCallSiteDescriptor();
74
75 GuardedInvocation inv;
76 if (self instanceof JSObject) {
77 inv = lookup(desc, request, linkerServices);
78 inv = inv.replaceMethods(linkerServices.filterInternalObjects(inv.getInvocation()), inv.getGuard());
79 } else if (self instanceof Map || self instanceof Bindings) {
80 // guard to make sure the Map or Bindings does not turn into JSObject later!
81 final GuardedInvocation beanInv = nashornBeansLinker.getGuardedInvocation(request, linkerServices);
82 inv = new GuardedInvocation(beanInv.getInvocation(),
83 NashornGuards.combineGuards(beanInv.getGuard(), NashornGuards.getNotJSObjectGuard()));
84 } else {
85 throw new AssertionError(); // Should never reach here.
86 }
87
88 return Bootstrap.asTypeSafeReturn(inv, linkerServices, desc);
89 }
90
91 private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
92 final StandardOperation op = NashornCallSiteDescriptor.getFirstStandardOperation(desc);
93 if (op == null) {
94 return null;
95 }
96 final String name = NashornCallSiteDescriptor.getOperand(desc);
97 switch (op) {
98 case GET_PROPERTY:
99 case GET_ELEMENT:
100 case GET_METHOD:
101 if (name != null) {
102 return findGetMethod(name);
103 }
104 // For indexed get, we want get GuardedInvocation beans linker and pass it.
105 // JSObjectLinker.get uses this fallback getter for explicit signature method access.
106 return findGetIndexMethod(nashornBeansLinker.getGuardedInvocation(request, linkerServices));
107 case SET_PROPERTY:
108 case SET_ELEMENT:
109 return name != null ? findSetMethod(name) : findSetIndexMethod();
110 case CALL:
111 return findCallMethod(desc);
112 case NEW:
113 return findNewMethod(desc);
114 default:
115 }
116 return null;
117 }
118
119 private static GuardedInvocation findGetMethod(final String name) {
120 final MethodHandle getter = MH.insertArguments(JSOBJECT_GETMEMBER, 1, name);
121 return new GuardedInvocation(getter, IS_JSOBJECT_GUARD);
122 }
123
124 private static GuardedInvocation findGetIndexMethod(final GuardedInvocation inv) {
125 final MethodHandle getter = MH.insertArguments(JSOBJECTLINKER_GET, 0, inv.getInvocation());
126 return inv.replaceMethods(getter, inv.getGuard());
127 }
128
129 private static GuardedInvocation findSetMethod(final String name) {
130 final MethodHandle getter = MH.insertArguments(JSOBJECT_SETMEMBER, 1, name);
131 return new GuardedInvocation(getter, IS_JSOBJECT_GUARD);
132 }
133
134 private static GuardedInvocation findSetIndexMethod() {
135 return new GuardedInvocation(JSOBJECTLINKER_PUT, IS_JSOBJECT_GUARD);
136 }
137
138 private static GuardedInvocation findCallMethod(final CallSiteDescriptor desc) {
139 MethodHandle mh = JSOBJECT_CALL;
140 if (NashornCallSiteDescriptor.isApplyToCall(desc)) {
141 mh = MH.insertArguments(JSOBJECT_CALL_TO_APPLY, 0, JSOBJECT_CALL);
142 }
143 final MethodType type = desc.getMethodType();
144 mh = type.parameterType(type.parameterCount() - 1) == Object[].class ?
145 mh :
146 MH.asCollector(mh, Object[].class, type.parameterCount() - 2);
147 return new GuardedInvocation(mh, IS_JSOBJECT_GUARD);
148 }
149
150 private static GuardedInvocation findNewMethod(final CallSiteDescriptor desc) {
151 final MethodHandle func = MH.asCollector(JSOBJECT_NEW, Object[].class, desc.getMethodType().parameterCount() - 1);
152 return new GuardedInvocation(func, IS_JSOBJECT_GUARD);
153 }
154
155 @SuppressWarnings("unused")
156 private static boolean isJSObject(final Object self) {
157 return self instanceof JSObject;
158 }
159
160 @SuppressWarnings("unused")
161 private static Object get(final MethodHandle fallback, final Object jsobj, final Object key)
162 throws Throwable {
163 if (key instanceof Integer) {
164 return ((JSObject)jsobj).getSlot((Integer)key);
165 } else if (key instanceof Number) {
166 final int index = getIndex((Number)key);
167 if (index > -1) {
168 return ((JSObject)jsobj).getSlot(index);
169 }
170 } else if (isString(key)) {
171 final String name = key.toString();
172 // get with method name and signature. delegate it to beans linker!
173 if (name.indexOf('(') != -1) {
174 return fallback.invokeExact(jsobj, (Object) name);
175 }
176 return ((JSObject)jsobj).getMember(name);
177 }
178 return null;
179 }
180
181 @SuppressWarnings("unused")
182 private static void put(final Object jsobj, final Object key, final Object value) {
183 if (key instanceof Integer) {
184 ((JSObject)jsobj).setSlot((Integer)key, value);
185 } else if (key instanceof Number) {
186 ((JSObject)jsobj).setSlot(getIndex((Number)key), value);
187 } else if (isString(key)) {
188 ((JSObject)jsobj).setMember(key.toString(), value);
189 }
190 }
191
192 private static int getIndex(final Number n) {
193 final double value = n.doubleValue();
194 return JSType.isRepresentableAsInt(value) ? (int)value : -1;
195 }
196
197 @SuppressWarnings("unused")
198 private static Object callToApply(final MethodHandle mh, final JSObject obj, final Object thiz, final Object... args) {
199 assert args.length >= 2;
200 final Object receiver = args[0];
201 final Object[] arguments = new Object[args.length - 1];
202 System.arraycopy(args, 1, arguments, 0, arguments.length);
203 try {
204 return mh.invokeExact(obj, thiz, new Object[] { receiver, arguments });
205 } catch (final RuntimeException | Error e) {
206 throw e;
207 } catch (final Throwable e) {
208 throw new RuntimeException(e);
209 }
210 }
211
212 private static final MethodHandleFunctionality MH = MethodHandleFactory.getFunctionality();
213
214 // method handles of the current class
215 private static final MethodHandle IS_JSOBJECT_GUARD = findOwnMH_S("isJSObject", boolean.class, Object.class);
216 private static final MethodHandle JSOBJECTLINKER_GET = findOwnMH_S("get", Object.class, MethodHandle.class, Object.class, Object.class);
217 private static final MethodHandle JSOBJECTLINKER_PUT = findOwnMH_S("put", Void.TYPE, Object.class, Object.class, Object.class);
218
219 // method handles of JSObject class
220 private static final MethodHandle JSOBJECT_GETMEMBER = findJSObjectMH_V("getMember", Object.class, String.class);
221 private static final MethodHandle JSOBJECT_SETMEMBER = findJSObjectMH_V("setMember", Void.TYPE, String.class, Object.class);
222 private static final MethodHandle JSOBJECT_CALL = findJSObjectMH_V("call", Object.class, Object.class, Object[].class);
223 private static final MethodHandle JSOBJECT_CALL_TO_APPLY = findOwnMH_S("callToApply", Object.class, MethodHandle.class, JSObject.class, Object.class, Object[].class);
224 private static final MethodHandle JSOBJECT_NEW = findJSObjectMH_V("newObject", Object.class, Object[].class);
225
226 private static MethodHandle findJSObjectMH_V(final String name, final Class<?> rtype, final Class<?>... types) {
227 return MH.findVirtual(MethodHandles.lookup(), JSObject.class, name, MH.type(rtype, types));
228 }
229
230 private static MethodHandle findOwnMH_S(final String name, final Class<?> rtype, final Class<?>... types) {
231 return MH.findStatic(MethodHandles.lookup(), JSObjectLinker.class, name, MH.type(rtype, types));
232 }
233 }