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.api.scripting; 27 28 import static jdk.nashorn.internal.runtime.Source.sourceFor; 29 30 import java.io.IOException; 31 import java.io.Reader; 32 import java.lang.invoke.MethodHandles; 33 import java.lang.reflect.Method; 34 import java.lang.reflect.Modifier; 35 import java.security.AccessControlContext; 36 import java.security.AccessController; 37 import java.security.Permissions; 38 import java.security.PrivilegedAction; 39 import java.security.ProtectionDomain; 40 import java.text.MessageFormat; 41 import java.util.Locale; 42 import java.util.Objects; 43 import java.util.ResourceBundle; 44 import javax.script.AbstractScriptEngine; 45 import javax.script.Bindings; 46 import javax.script.Compilable; 47 import javax.script.CompiledScript; 48 import javax.script.Invocable; 49 import javax.script.ScriptContext; 50 import javax.script.ScriptEngine; 51 import javax.script.ScriptEngineFactory; 52 import javax.script.ScriptException; 53 import javax.script.SimpleBindings; 54 import jdk.nashorn.internal.objects.Global; 55 import jdk.nashorn.internal.runtime.Context; 56 import jdk.nashorn.internal.runtime.ErrorManager; 57 import jdk.nashorn.internal.runtime.ScriptFunction; 58 import jdk.nashorn.internal.runtime.ScriptObject; 59 import jdk.nashorn.internal.runtime.ScriptRuntime; 60 import jdk.nashorn.internal.runtime.Source; 61 import jdk.nashorn.internal.runtime.linker.JavaAdapterFactory; 62 import jdk.nashorn.internal.runtime.options.Options; 63 64 /** 65 * JSR-223 compliant script engine for Nashorn. Instances are not created directly, but rather returned through 66 * {@link NashornScriptEngineFactory#getScriptEngine()}. Note that this engine implements the {@link Compilable} and 67 * {@link Invocable} interfaces, allowing for efficient precompilation and repeated execution of scripts. 68 * @see NashornScriptEngineFactory 69 * 70 * @since 1.8u40 71 */ 72 @jdk.Exported 73 public final class NashornScriptEngine extends AbstractScriptEngine implements Compilable, Invocable { 74 /** 75 * Key used to associate Nashorn global object mirror with arbitrary Bindings instance. 76 */ 77 public static final String NASHORN_GLOBAL = "nashorn.global"; 78 79 // commonly used access control context objects 80 private static AccessControlContext createPermAccCtxt(final String permName) { 81 final Permissions perms = new Permissions(); 82 perms.add(new RuntimePermission(permName)); 83 return new AccessControlContext(new ProtectionDomain[] { new ProtectionDomain(null, perms) }); 84 } 85 86 private static final AccessControlContext CREATE_CONTEXT_ACC_CTXT = createPermAccCtxt(Context.NASHORN_CREATE_CONTEXT); 87 private static final AccessControlContext CREATE_GLOBAL_ACC_CTXT = createPermAccCtxt(Context.NASHORN_CREATE_GLOBAL); 88 89 // the factory that created this engine 90 private final ScriptEngineFactory factory; 91 // underlying nashorn Context - 1:1 with engine instance 92 private final Context nashornContext; 93 // do we want to share single Nashorn global instance across ENGINE_SCOPEs? 94 private final boolean _global_per_engine; 95 // This is the initial default Nashorn global object. 96 // This is used as "shared" global if above option is true. 97 private final Global global; 98 99 // Nashorn script engine error message management 100 private static final String MESSAGES_RESOURCE = "jdk.nashorn.api.scripting.resources.Messages"; 101 102 private static final ResourceBundle MESSAGES_BUNDLE; 103 static { 104 MESSAGES_BUNDLE = ResourceBundle.getBundle(MESSAGES_RESOURCE, Locale.getDefault()); 105 } 106 107 // helper to get Nashorn script engine error message 108 private static String getMessage(final String msgId, final String... args) { 109 try { 110 return new MessageFormat(MESSAGES_BUNDLE.getString(msgId)).format(args); 111 } catch (final java.util.MissingResourceException e) { 112 throw new RuntimeException("no message resource found for message id: "+ msgId); 113 } 114 } 115 116 NashornScriptEngine(final NashornScriptEngineFactory factory, final String[] args, final ClassLoader appLoader, final ClassFilter classFilter) { 117 assert args != null : "null argument array"; 118 this.factory = factory; 119 final Options options = new Options("nashorn"); 120 options.process(args); 121 122 // throw ParseException on first error from script 123 final ErrorManager errMgr = new Context.ThrowErrorManager(); 124 // create new Nashorn Context 125 this.nashornContext = AccessController.doPrivileged(new PrivilegedAction<Context>() { 126 @Override 127 public Context run() { 128 try { 129 return new Context(options, errMgr, appLoader, classFilter); 130 } catch (final RuntimeException e) { 131 if (Context.DEBUG) { 132 e.printStackTrace(); 133 } 134 throw e; 135 } 136 } 137 }, CREATE_CONTEXT_ACC_CTXT); 138 139 // cache this option that is used often 140 this._global_per_engine = nashornContext.getEnv()._global_per_engine; 141 142 // create new global object 143 this.global = createNashornGlobal(context); 144 // set the default ENGINE_SCOPE object for the default context 145 context.setBindings(new ScriptObjectMirror(global, global), ScriptContext.ENGINE_SCOPE); 146 } 147 148 @Override 149 public Object eval(final Reader reader, final ScriptContext ctxt) throws ScriptException { 150 return evalImpl(makeSource(reader, ctxt), ctxt); 151 } 152 153 @Override 154 public Object eval(final String script, final ScriptContext ctxt) throws ScriptException { 155 return evalImpl(makeSource(script, ctxt), ctxt); 156 } 157 158 @Override 159 public ScriptEngineFactory getFactory() { 160 return factory; 161 } 162 163 @Override 164 public Bindings createBindings() { 165 if (_global_per_engine) { 166 // just create normal SimpleBindings. 167 // We use same 'global' for all Bindings. 168 return new SimpleBindings(); 169 } 170 return createGlobalMirror(null); 171 } 172 173 // Compilable methods 174 175 @Override 176 public CompiledScript compile(final Reader reader) throws ScriptException { 177 return asCompiledScript(makeSource(reader, context)); 178 } 179 180 @Override 181 public CompiledScript compile(final String str) throws ScriptException { 182 return asCompiledScript(makeSource(str, context)); 183 } 184 185 // Invocable methods 186 187 @Override 188 public Object invokeFunction(final String name, final Object... args) 189 throws ScriptException, NoSuchMethodException { 190 return invokeImpl(null, name, args); 191 } 192 193 @Override 194 public Object invokeMethod(final Object thiz, final String name, final Object... args) 195 throws ScriptException, NoSuchMethodException { 196 if (thiz == null) { 197 throw new IllegalArgumentException(getMessage("thiz.cannot.be.null")); 198 } 199 return invokeImpl(thiz, name, args); 200 } 201 202 @Override 203 public <T> T getInterface(final Class<T> clazz) { 204 return getInterfaceInner(null, clazz); 205 } 206 207 @Override 208 public <T> T getInterface(final Object thiz, final Class<T> clazz) { 209 if (thiz == null) { 210 throw new IllegalArgumentException(getMessage("thiz.cannot.be.null")); 211 } 212 return getInterfaceInner(thiz, clazz); 213 } 214 215 // Implementation only below this point 216 217 private static Source makeSource(final Reader reader, final ScriptContext ctxt) throws ScriptException { 218 try { 219 return sourceFor(getScriptName(ctxt), reader); 220 } catch (final IOException e) { 221 throw new ScriptException(e); 222 } 223 } 224 225 private static Source makeSource(final String src, final ScriptContext ctxt) { 226 return sourceFor(getScriptName(ctxt), src); 227 } 228 229 private static String getScriptName(final ScriptContext ctxt) { 230 final Object val = ctxt.getAttribute(ScriptEngine.FILENAME); 231 return (val != null) ? val.toString() : "<eval>"; 232 } 233 234 private <T> T getInterfaceInner(final Object thiz, final Class<T> clazz) { 235 assert !(thiz instanceof ScriptObject) : "raw ScriptObject not expected here"; 236 237 if (clazz == null || !clazz.isInterface()) { 238 throw new IllegalArgumentException(getMessage("interface.class.expected")); 239 } 240 241 // perform security access check as early as possible 242 final SecurityManager sm = System.getSecurityManager(); 243 if (sm != null) { 244 if (! Modifier.isPublic(clazz.getModifiers())) { 245 throw new SecurityException(getMessage("implementing.non.public.interface", clazz.getName())); 246 } 247 Context.checkPackageAccess(clazz); 248 } 249 250 ScriptObject realSelf = null; 251 Global realGlobal = null; 252 if(thiz == null) { 253 // making interface out of global functions 254 realSelf = realGlobal = getNashornGlobalFrom(context); 255 } else if (thiz instanceof ScriptObjectMirror) { 256 final ScriptObjectMirror mirror = (ScriptObjectMirror)thiz; 257 realSelf = mirror.getScriptObject(); 258 realGlobal = mirror.getHomeGlobal(); 259 if (! isOfContext(realGlobal, nashornContext)) { 260 throw new IllegalArgumentException(getMessage("script.object.from.another.engine")); 261 } 262 } 263 264 if (realSelf == null) { 265 throw new IllegalArgumentException(getMessage("interface.on.non.script.object")); 266 } 267 268 try { 269 final Global oldGlobal = Context.getGlobal(); 270 final boolean globalChanged = (oldGlobal != realGlobal); 271 try { 272 if (globalChanged) { 273 Context.setGlobal(realGlobal); 274 } 275 276 if (! isInterfaceImplemented(clazz, realSelf)) { 277 return null; 278 } 279 return clazz.cast(JavaAdapterFactory.getConstructor(realSelf.getClass(), clazz, 280 MethodHandles.publicLookup()).invoke(realSelf)); 281 } finally { 282 if (globalChanged) { 283 Context.setGlobal(oldGlobal); 284 } 285 } 286 } catch(final RuntimeException|Error e) { 287 throw e; 288 } catch(final Throwable t) { 289 throw new RuntimeException(t); 290 } 291 } 292 293 // Retrieve nashorn Global object for a given ScriptContext object 294 private Global getNashornGlobalFrom(final ScriptContext ctxt) { 295 if (_global_per_engine) { 296 // shared single global object for all ENGINE_SCOPE Bindings 297 return global; 298 } 299 300 final Bindings bindings = ctxt.getBindings(ScriptContext.ENGINE_SCOPE); 301 // is this Nashorn's own Bindings implementation? 302 if (bindings instanceof ScriptObjectMirror) { 303 final Global glob = globalFromMirror((ScriptObjectMirror)bindings); 304 if (glob != null) { 305 return glob; 306 } 307 } 308 309 // Arbitrary user Bindings implementation. Look for NASHORN_GLOBAL in it! 310 final Object scope = bindings.get(NASHORN_GLOBAL); 311 if (scope instanceof ScriptObjectMirror) { 312 final Global glob = globalFromMirror((ScriptObjectMirror)scope); 313 if (glob != null) { 314 return glob; 315 } 316 } 317 318 // We didn't find associated nashorn global mirror in the Bindings given! 319 // Create new global instance mirror and associate with the Bindings. 320 final ScriptObjectMirror mirror = createGlobalMirror(ctxt); 321 bindings.put(NASHORN_GLOBAL, mirror); 322 return mirror.getHomeGlobal(); 323 } 324 325 // Retrieve nashorn Global object from a given ScriptObjectMirror 326 private Global globalFromMirror(final ScriptObjectMirror mirror) { 327 final ScriptObject sobj = mirror.getScriptObject(); 328 if (sobj instanceof Global && isOfContext((Global)sobj, nashornContext)) { 329 return (Global)sobj; 330 } 331 332 return null; 333 } 334 335 // Create a new ScriptObjectMirror wrapping a newly created Nashorn Global object 336 private ScriptObjectMirror createGlobalMirror(final ScriptContext ctxt) { 337 final Global newGlobal = createNashornGlobal(ctxt); 338 return new ScriptObjectMirror(newGlobal, newGlobal); 339 } 340 341 // Create a new Nashorn Global object 342 private Global createNashornGlobal(final ScriptContext ctxt) { 343 final Global newGlobal = AccessController.doPrivileged(new PrivilegedAction<Global>() { 344 @Override 345 public Global run() { 346 try { 347 return nashornContext.newGlobal(); 348 } catch (final RuntimeException e) { 349 if (Context.DEBUG) { 350 e.printStackTrace(); 351 } 352 throw e; 353 } 354 } 355 }, CREATE_GLOBAL_ACC_CTXT); 356 357 nashornContext.initGlobal(newGlobal, this); 358 newGlobal.setScriptContext(ctxt); 359 360 return newGlobal; 361 } 362 363 private Object invokeImpl(final Object selfObject, final String name, final Object... args) throws ScriptException, NoSuchMethodException { 364 Objects.requireNonNull(name); 365 assert !(selfObject instanceof ScriptObject) : "raw ScriptObject not expected here"; 366 367 Global invokeGlobal = null; 368 ScriptObjectMirror selfMirror = null; 369 if (selfObject instanceof ScriptObjectMirror) { 370 selfMirror = (ScriptObjectMirror)selfObject; 371 if (! isOfContext(selfMirror.getHomeGlobal(), nashornContext)) { 372 throw new IllegalArgumentException(getMessage("script.object.from.another.engine")); 373 } 374 invokeGlobal = selfMirror.getHomeGlobal(); 375 } else if (selfObject == null) { 376 // selfObject is null => global function call 377 final Global ctxtGlobal = getNashornGlobalFrom(context); 378 invokeGlobal = ctxtGlobal; 379 selfMirror = (ScriptObjectMirror)ScriptObjectMirror.wrap(ctxtGlobal, ctxtGlobal); 380 } 381 382 if (selfMirror != null) { 383 try { 384 return ScriptObjectMirror.translateUndefined(selfMirror.callMember(name, args)); 385 } catch (final Exception e) { 386 final Throwable cause = e.getCause(); 387 if (cause instanceof NoSuchMethodException) { 388 throw (NoSuchMethodException)cause; 389 } 390 throwAsScriptException(e, invokeGlobal); 391 throw new AssertionError("should not reach here"); 392 } 393 } 394 395 // Non-script object passed as selfObject 396 throw new IllegalArgumentException(getMessage("interface.on.non.script.object")); 397 } 398 399 private Object evalImpl(final Source src, final ScriptContext ctxt) throws ScriptException { 400 return evalImpl(compileImpl(src, ctxt), ctxt); 401 } 402 403 private Object evalImpl(final ScriptFunction script, final ScriptContext ctxt) throws ScriptException { 404 return evalImpl(script, ctxt, getNashornGlobalFrom(ctxt)); 405 } 406 407 private static Object evalImpl(final Context.MultiGlobalCompiledScript mgcs, final ScriptContext ctxt, final Global ctxtGlobal) throws ScriptException { 408 final Global oldGlobal = Context.getGlobal(); 409 final boolean globalChanged = (oldGlobal != ctxtGlobal); 410 try { 411 if (globalChanged) { 412 Context.setGlobal(ctxtGlobal); 413 } 414 415 final ScriptFunction script = mgcs.getFunction(ctxtGlobal); 416 ctxtGlobal.setScriptContext(ctxt); 417 return ScriptObjectMirror.translateUndefined(ScriptObjectMirror.wrap(ScriptRuntime.apply(script, ctxtGlobal), ctxtGlobal)); 418 } catch (final Exception e) { 419 throwAsScriptException(e, ctxtGlobal); 420 throw new AssertionError("should not reach here"); 421 } finally { 422 if (globalChanged) { 423 Context.setGlobal(oldGlobal); 424 } 425 } 426 } 427 428 private static Object evalImpl(final ScriptFunction script, final ScriptContext ctxt, final Global ctxtGlobal) throws ScriptException { 429 if (script == null) { 430 return null; 431 } 432 final Global oldGlobal = Context.getGlobal(); 433 final boolean globalChanged = (oldGlobal != ctxtGlobal); 434 try { 435 if (globalChanged) { 436 Context.setGlobal(ctxtGlobal); 437 } 438 439 ctxtGlobal.setScriptContext(ctxt); 440 return ScriptObjectMirror.translateUndefined(ScriptObjectMirror.wrap(ScriptRuntime.apply(script, ctxtGlobal), ctxtGlobal)); 441 } catch (final Exception e) { 442 throwAsScriptException(e, ctxtGlobal); 443 throw new AssertionError("should not reach here"); 444 } finally { 445 if (globalChanged) { 446 Context.setGlobal(oldGlobal); 447 } 448 } 449 } 450 451 private static void throwAsScriptException(final Exception e, final Global global) throws ScriptException { 452 if (e instanceof ScriptException) { 453 throw (ScriptException)e; 454 } else if (e instanceof NashornException) { 455 final NashornException ne = (NashornException)e; 456 final ScriptException se = new ScriptException( 457 ne.getMessage(), ne.getFileName(), 458 ne.getLineNumber(), ne.getColumnNumber()); 459 ne.initEcmaError(global); 460 se.initCause(e); 461 throw se; 462 } else if (e instanceof RuntimeException) { 463 throw (RuntimeException)e; 464 } else { 465 // wrap any other exception as ScriptException 466 throw new ScriptException(e); 467 } 468 } 469 470 private CompiledScript asCompiledScript(final Source source) throws ScriptException { 471 final Context.MultiGlobalCompiledScript mgcs; 472 final ScriptFunction func; 473 final Global oldGlobal = Context.getGlobal(); 474 final Global newGlobal = getNashornGlobalFrom(context); 475 final boolean globalChanged = (oldGlobal != newGlobal); 476 try { 477 if (globalChanged) { 478 Context.setGlobal(newGlobal); 479 } 480 481 mgcs = nashornContext.compileScript(source); 482 func = mgcs.getFunction(newGlobal); 483 } catch (final Exception e) { 484 throwAsScriptException(e, newGlobal); 485 throw new AssertionError("should not reach here"); 486 } finally { 487 if (globalChanged) { 488 Context.setGlobal(oldGlobal); 489 } 490 } 491 492 return new CompiledScript() { 493 @Override 494 public Object eval(final ScriptContext ctxt) throws ScriptException { 495 final Global globalObject = getNashornGlobalFrom(ctxt); 496 // Are we running the script in the same global in which it was compiled? 497 if (func.getScope() == globalObject) { 498 return evalImpl(func, ctxt, globalObject); 499 } 500 501 // different global 502 return evalImpl(mgcs, ctxt, globalObject); 503 } 504 @Override 505 public ScriptEngine getEngine() { 506 return NashornScriptEngine.this; 507 } 508 }; 509 } 510 511 private ScriptFunction compileImpl(final Source source, final ScriptContext ctxt) throws ScriptException { 512 return compileImpl(source, getNashornGlobalFrom(ctxt)); 513 } 514 515 private ScriptFunction compileImpl(final Source source, final Global newGlobal) throws ScriptException { 516 final Global oldGlobal = Context.getGlobal(); 517 final boolean globalChanged = (oldGlobal != newGlobal); 518 try { 519 if (globalChanged) { 520 Context.setGlobal(newGlobal); 521 } 522 523 return nashornContext.compileScript(source, newGlobal); 524 } catch (final Exception e) { 525 throwAsScriptException(e, newGlobal); 526 throw new AssertionError("should not reach here"); 527 } finally { 528 if (globalChanged) { 529 Context.setGlobal(oldGlobal); 530 } 531 } 532 } 533 534 private static boolean isInterfaceImplemented(final Class<?> iface, final ScriptObject sobj) { 535 for (final Method method : iface.getMethods()) { 536 // ignore methods of java.lang.Object class 537 if (method.getDeclaringClass() == Object.class) { 538 continue; 539 } 540 541 // skip check for default methods - non-abstract, interface methods 542 if (! Modifier.isAbstract(method.getModifiers())) { 543 continue; 544 } 545 546 final Object obj = sobj.get(method.getName()); 547 if (! (obj instanceof ScriptFunction)) { 548 return false; 549 } 550 } 551 return true; 552 } 553 554 private static boolean isOfContext(final Global global, final Context context) { 555 return global.isOfContext(context); 556 } 557 }