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