1 /* 2 * Copyright (c) 2014, 2020, 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 java.lang; 27 28 import java.io.IOException; 29 import java.io.InputStream; 30 import java.lang.annotation.Annotation; 31 import java.lang.module.Configuration; 32 import java.lang.module.ModuleReference; 33 import java.lang.module.ModuleDescriptor; 34 import java.lang.module.ModuleDescriptor.Exports; 35 import java.lang.module.ModuleDescriptor.Opens; 36 import java.lang.module.ModuleDescriptor.Version; 37 import java.lang.module.ResolvedModule; 38 import java.lang.reflect.AnnotatedElement; 39 import java.net.URI; 40 import java.net.URL; 41 import java.security.AccessController; 42 import java.security.PrivilegedAction; 43 import java.util.HashMap; 44 import java.util.HashSet; 45 import java.util.List; 46 import java.util.Map; 47 import java.util.Objects; 48 import java.util.Optional; 49 import java.util.Set; 50 import java.util.concurrent.ConcurrentHashMap; 51 import java.util.function.Function; 52 import java.util.stream.Collectors; 53 import java.util.stream.Stream; 54 55 import jdk.internal.loader.BuiltinClassLoader; 56 import jdk.internal.loader.BootLoader; 57 import jdk.internal.loader.ClassLoaders; 58 import jdk.internal.module.IllegalAccessLogger; 59 import jdk.internal.module.ModuleLoaderMap; 60 import jdk.internal.module.ServicesCatalog; 61 import jdk.internal.module.Resources; 62 import jdk.internal.org.objectweb.asm.AnnotationVisitor; 63 import jdk.internal.org.objectweb.asm.Attribute; 64 import jdk.internal.org.objectweb.asm.ClassReader; 65 import jdk.internal.org.objectweb.asm.ClassVisitor; 66 import jdk.internal.org.objectweb.asm.ClassWriter; 67 import jdk.internal.org.objectweb.asm.ModuleVisitor; 68 import jdk.internal.org.objectweb.asm.Opcodes; 69 import jdk.internal.reflect.CallerSensitive; 70 import jdk.internal.reflect.Reflection; 71 import sun.security.util.SecurityConstants; 72 73 /** 74 * Represents a run-time module, either {@link #isNamed() named} or unnamed. 75 * 76 * <p> Named modules have a {@link #getName() name} and are constructed by the 77 * Java Virtual Machine when a graph of modules is defined to the Java virtual 78 * machine to create a {@linkplain ModuleLayer module layer}. </p> 79 * 80 * <p> An unnamed module does not have a name. There is an unnamed module for 81 * each {@link ClassLoader ClassLoader}, obtained by invoking its {@link 82 * ClassLoader#getUnnamedModule() getUnnamedModule} method. All types that are 83 * not in a named module are members of their defining class loader's unnamed 84 * module. </p> 85 * 86 * <p> The package names that are parameters or returned by methods defined in 87 * this class are the fully-qualified names of the packages as defined in 88 * section {@jls 6.5.3} of <cite>The Java Language Specification</cite>, for 89 * example, {@code "java.lang"}. </p> 90 * 91 * <p> Unless otherwise specified, passing a {@code null} argument to a method 92 * in this class causes a {@link NullPointerException NullPointerException} to 93 * be thrown. </p> 94 * 95 * @since 9 96 * @spec JPMS 97 * @see Class#getModule() 98 */ 99 100 public final class Module implements AnnotatedElement { 101 102 // the layer that contains this module, can be null 103 private final ModuleLayer layer; 104 105 // module name and loader, these fields are read by VM 106 private final String name; 107 private final ClassLoader loader; 108 109 // the module descriptor 110 private final ModuleDescriptor descriptor; 111 112 113 /** 114 * Creates a new named Module. The resulting Module will be defined to the 115 * VM but will not read any other modules, will not have any exports setup 116 * and will not be registered in the service catalog. 117 */ 118 Module(ModuleLayer layer, 119 ClassLoader loader, 120 ModuleDescriptor descriptor, 121 URI uri) 122 { 123 this.layer = layer; 124 this.name = descriptor.name(); 125 this.loader = loader; 126 this.descriptor = descriptor; 127 128 // define module to VM 129 130 boolean isOpen = descriptor.isOpen() || descriptor.isAutomatic(); 131 Version version = descriptor.version().orElse(null); 132 String vs = Objects.toString(version, null); 133 String loc = Objects.toString(uri, null); 134 Object[] packages = descriptor.packages().toArray(); 135 defineModule0(this, isOpen, vs, loc, packages); 136 } 137 138 139 /** 140 * Create the unnamed Module for the given ClassLoader. 141 * 142 * @see ClassLoader#getUnnamedModule 143 */ 144 Module(ClassLoader loader) { 145 this.layer = null; 146 this.name = null; 147 this.loader = loader; 148 this.descriptor = null; 149 } 150 151 152 /** 153 * Creates a named module but without defining the module to the VM. 154 * 155 * @apiNote This constructor is for VM white-box testing. 156 */ 157 Module(ClassLoader loader, ModuleDescriptor descriptor) { 158 this.layer = null; 159 this.name = descriptor.name(); 160 this.loader = loader; 161 this.descriptor = descriptor; 162 } 163 164 165 /** 166 * Returns {@code true} if this module is a named module. 167 * 168 * @return {@code true} if this is a named module 169 * 170 * @see ClassLoader#getUnnamedModule() 171 */ 172 public boolean isNamed() { 173 return name != null; 174 } 175 176 /** 177 * Returns the module name or {@code null} if this module is an unnamed 178 * module. 179 * 180 * @return The module name 181 */ 182 public String getName() { 183 return name; 184 } 185 186 /** 187 * Returns the {@code ClassLoader} for this module. 188 * 189 * <p> If there is a security manager then its {@code checkPermission} 190 * method if first called with a {@code RuntimePermission("getClassLoader")} 191 * permission to check that the caller is allowed to get access to the 192 * class loader. </p> 193 * 194 * @return The class loader for this module 195 * 196 * @throws SecurityException 197 * If denied by the security manager 198 */ 199 public ClassLoader getClassLoader() { 200 SecurityManager sm = System.getSecurityManager(); 201 if (sm != null) { 202 sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION); 203 } 204 return loader; 205 } 206 207 /** 208 * Returns the module descriptor for this module or {@code null} if this 209 * module is an unnamed module. 210 * 211 * @return The module descriptor for this module 212 */ 213 public ModuleDescriptor getDescriptor() { 214 return descriptor; 215 } 216 217 /** 218 * Returns the module layer that contains this module or {@code null} if 219 * this module is not in a module layer. 220 * 221 * A module layer contains named modules and therefore this method always 222 * returns {@code null} when invoked on an unnamed module. 223 * 224 * <p> <a href="reflect/Proxy.html#dynamicmodule">Dynamic modules</a> are 225 * named modules that are generated at runtime. A dynamic module may or may 226 * not be in a module layer. </p> 227 * 228 * @return The module layer that contains this module 229 * 230 * @see java.lang.reflect.Proxy 231 */ 232 public ModuleLayer getLayer() { 233 if (isNamed()) { 234 ModuleLayer layer = this.layer; 235 if (layer != null) 236 return layer; 237 238 // special-case java.base as it is created before the boot layer 239 if (loader == null && name.equals("java.base")) { 240 return ModuleLayer.boot(); 241 } 242 } 243 return null; 244 } 245 246 // -- 247 248 // special Module to mean "all unnamed modules" 249 private static final Module ALL_UNNAMED_MODULE = new Module(null); 250 private static final Set<Module> ALL_UNNAMED_MODULE_SET = Set.of(ALL_UNNAMED_MODULE); 251 252 // special Module to mean "everyone" 253 private static final Module EVERYONE_MODULE = new Module(null); 254 private static final Set<Module> EVERYONE_SET = Set.of(EVERYONE_MODULE); 255 256 /** 257 * The holder of data structures to support readability, exports, and 258 * service use added at runtime with the reflective APIs. 259 */ 260 private static class ReflectionData { 261 /** 262 * A module (1st key) reads another module (2nd key) 263 */ 264 static final WeakPairMap<Module, Module, Boolean> reads = 265 new WeakPairMap<>(); 266 267 /** 268 * A module (1st key) exports or opens a package to another module 269 * (2nd key). The map value is a map of package name to a boolean 270 * that indicates if the package is opened. 271 */ 272 static final WeakPairMap<Module, Module, Map<String, Boolean>> exports = 273 new WeakPairMap<>(); 274 275 /** 276 * A module (1st key) uses a service (2nd key) 277 */ 278 static final WeakPairMap<Module, Class<?>, Boolean> uses = 279 new WeakPairMap<>(); 280 } 281 282 283 // -- readability -- 284 285 // the modules that this module reads 286 private volatile Set<Module> reads; 287 288 /** 289 * Indicates if this module reads the given module. This method returns 290 * {@code true} if invoked to test if this module reads itself. It also 291 * returns {@code true} if invoked on an unnamed module (as unnamed 292 * modules read all modules). 293 * 294 * @param other 295 * The other module 296 * 297 * @return {@code true} if this module reads {@code other} 298 * 299 * @see #addReads(Module) 300 */ 301 public boolean canRead(Module other) { 302 Objects.requireNonNull(other); 303 304 // an unnamed module reads all modules 305 if (!this.isNamed()) 306 return true; 307 308 // all modules read themselves 309 if (other == this) 310 return true; 311 312 // check if this module reads other 313 if (other.isNamed()) { 314 Set<Module> reads = this.reads; // volatile read 315 if (reads != null && reads.contains(other)) 316 return true; 317 } 318 319 // check if this module reads the other module reflectively 320 if (ReflectionData.reads.containsKeyPair(this, other)) 321 return true; 322 323 // if other is an unnamed module then check if this module reads 324 // all unnamed modules 325 if (!other.isNamed() 326 && ReflectionData.reads.containsKeyPair(this, ALL_UNNAMED_MODULE)) 327 return true; 328 329 return false; 330 } 331 332 /** 333 * If the caller's module is this module then update this module to read 334 * the given module. 335 * 336 * This method is a no-op if {@code other} is this module (all modules read 337 * themselves), this module is an unnamed module (as unnamed modules read 338 * all modules), or this module already reads {@code other}. 339 * 340 * @implNote <em>Read edges</em> added by this method are <em>weak</em> and 341 * do not prevent {@code other} from being GC'ed when this module is 342 * strongly reachable. 343 * 344 * @param other 345 * The other module 346 * 347 * @return this module 348 * 349 * @throws IllegalCallerException 350 * If this is a named module and the caller's module is not this 351 * module 352 * 353 * @see #canRead 354 */ 355 @CallerSensitive 356 public Module addReads(Module other) { 357 Objects.requireNonNull(other); 358 if (this.isNamed()) { 359 Module caller = getCallerModule(Reflection.getCallerClass()); 360 if (caller != this) { 361 throw new IllegalCallerException(caller + " != " + this); 362 } 363 implAddReads(other, true); 364 } 365 return this; 366 } 367 368 /** 369 * Updates this module to read another module. 370 * 371 * @apiNote Used by the --add-reads command line option. 372 */ 373 void implAddReads(Module other) { 374 implAddReads(other, true); 375 } 376 377 /** 378 * Updates this module to read all unnamed modules. 379 * 380 * @apiNote Used by the --add-reads command line option. 381 */ 382 void implAddReadsAllUnnamed() { 383 implAddReads(Module.ALL_UNNAMED_MODULE, true); 384 } 385 386 /** 387 * Updates this module to read another module without notifying the VM. 388 * 389 * @apiNote This method is for VM white-box testing. 390 */ 391 void implAddReadsNoSync(Module other) { 392 implAddReads(other, false); 393 } 394 395 /** 396 * Makes the given {@code Module} readable to this module. 397 * 398 * If {@code syncVM} is {@code true} then the VM is notified. 399 */ 400 private void implAddReads(Module other, boolean syncVM) { 401 Objects.requireNonNull(other); 402 if (!canRead(other)) { 403 // update VM first, just in case it fails 404 if (syncVM) { 405 if (other == ALL_UNNAMED_MODULE) { 406 addReads0(this, null); 407 } else { 408 addReads0(this, other); 409 } 410 } 411 412 // add reflective read 413 ReflectionData.reads.putIfAbsent(this, other, Boolean.TRUE); 414 } 415 } 416 417 418 // -- exported and open packages -- 419 420 // the packages are open to other modules, can be null 421 // if the value contains EVERYONE_MODULE then the package is open to all 422 private volatile Map<String, Set<Module>> openPackages; 423 424 // the packages that are exported, can be null 425 // if the value contains EVERYONE_MODULE then the package is exported to all 426 private volatile Map<String, Set<Module>> exportedPackages; 427 428 /** 429 * Returns {@code true} if this module exports the given package to at 430 * least the given module. 431 * 432 * <p> This method returns {@code true} if invoked to test if a package in 433 * this module is exported to itself. It always returns {@code true} when 434 * invoked on an unnamed module. A package that is {@link #isOpen open} to 435 * the given module is considered exported to that module at run-time and 436 * so this method returns {@code true} if the package is open to the given 437 * module. </p> 438 * 439 * <p> This method does not check if the given module reads this module. </p> 440 * 441 * @param pn 442 * The package name 443 * @param other 444 * The other module 445 * 446 * @return {@code true} if this module exports the package to at least the 447 * given module 448 * 449 * @see ModuleDescriptor#exports() 450 * @see #addExports(String,Module) 451 */ 452 public boolean isExported(String pn, Module other) { 453 Objects.requireNonNull(pn); 454 Objects.requireNonNull(other); 455 return implIsExportedOrOpen(pn, other, /*open*/false); 456 } 457 458 /** 459 * Returns {@code true} if this module has <em>opened</em> a package to at 460 * least the given module. 461 * 462 * <p> This method returns {@code true} if invoked to test if a package in 463 * this module is open to itself. It returns {@code true} when invoked on an 464 * {@link ModuleDescriptor#isOpen open} module with a package in the module. 465 * It always returns {@code true} when invoked on an unnamed module. </p> 466 * 467 * <p> This method does not check if the given module reads this module. </p> 468 * 469 * @param pn 470 * The package name 471 * @param other 472 * The other module 473 * 474 * @return {@code true} if this module has <em>opened</em> the package 475 * to at least the given module 476 * 477 * @see ModuleDescriptor#opens() 478 * @see #addOpens(String,Module) 479 * @see java.lang.reflect.AccessibleObject#setAccessible(boolean) 480 * @see java.lang.invoke.MethodHandles#privateLookupIn 481 */ 482 public boolean isOpen(String pn, Module other) { 483 Objects.requireNonNull(pn); 484 Objects.requireNonNull(other); 485 return implIsExportedOrOpen(pn, other, /*open*/true); 486 } 487 488 /** 489 * Returns {@code true} if this module exports the given package 490 * unconditionally. 491 * 492 * <p> This method always returns {@code true} when invoked on an unnamed 493 * module. A package that is {@link #isOpen(String) opened} unconditionally 494 * is considered exported unconditionally at run-time and so this method 495 * returns {@code true} if the package is opened unconditionally. </p> 496 * 497 * <p> This method does not check if the given module reads this module. </p> 498 * 499 * @param pn 500 * The package name 501 * 502 * @return {@code true} if this module exports the package unconditionally 503 * 504 * @see ModuleDescriptor#exports() 505 */ 506 public boolean isExported(String pn) { 507 Objects.requireNonNull(pn); 508 return implIsExportedOrOpen(pn, EVERYONE_MODULE, /*open*/false); 509 } 510 511 /** 512 * Returns {@code true} if this module has <em>opened</em> a package 513 * unconditionally. 514 * 515 * <p> This method always returns {@code true} when invoked on an unnamed 516 * module. Additionally, it always returns {@code true} when invoked on an 517 * {@link ModuleDescriptor#isOpen open} module with a package in the 518 * module. </p> 519 * 520 * <p> This method does not check if the given module reads this module. </p> 521 * 522 * @param pn 523 * The package name 524 * 525 * @return {@code true} if this module has <em>opened</em> the package 526 * unconditionally 527 * 528 * @see ModuleDescriptor#opens() 529 */ 530 public boolean isOpen(String pn) { 531 Objects.requireNonNull(pn); 532 return implIsExportedOrOpen(pn, EVERYONE_MODULE, /*open*/true); 533 } 534 535 536 /** 537 * Returns {@code true} if this module exports or opens the given package 538 * to the given module. If the other module is {@code EVERYONE_MODULE} then 539 * this method tests if the package is exported or opened unconditionally. 540 */ 541 private boolean implIsExportedOrOpen(String pn, Module other, boolean open) { 542 // all packages in unnamed modules are open 543 if (!isNamed()) 544 return true; 545 546 // all packages are exported/open to self 547 if (other == this && descriptor.packages().contains(pn)) 548 return true; 549 550 // all packages in open and automatic modules are open 551 if (descriptor.isOpen() || descriptor.isAutomatic()) 552 return descriptor.packages().contains(pn); 553 554 // exported/opened via module declaration/descriptor 555 if (isStaticallyExportedOrOpen(pn, other, open)) 556 return true; 557 558 // exported via addExports/addOpens 559 if (isReflectivelyExportedOrOpen(pn, other, open)) 560 return true; 561 562 // not exported or open to other 563 return false; 564 } 565 566 /** 567 * Returns {@code true} if this module exports or opens a package to 568 * the given module via its module declaration or CLI options. 569 */ 570 private boolean isStaticallyExportedOrOpen(String pn, Module other, boolean open) { 571 // test if package is open to everyone or <other> 572 Map<String, Set<Module>> openPackages = this.openPackages; 573 if (openPackages != null && allows(openPackages.get(pn), other)) { 574 return true; 575 } 576 577 if (!open) { 578 // test package is exported to everyone or <other> 579 Map<String, Set<Module>> exportedPackages = this.exportedPackages; 580 if (exportedPackages != null && allows(exportedPackages.get(pn), other)) { 581 return true; 582 } 583 } 584 585 return false; 586 } 587 588 /** 589 * Returns {@code true} if targets is non-null and contains EVERYONE_MODULE 590 * or the given module. Also returns true if the given module is an unnamed 591 * module and targets contains ALL_UNNAMED_MODULE. 592 */ 593 private boolean allows(Set<Module> targets, Module module) { 594 if (targets != null) { 595 if (targets.contains(EVERYONE_MODULE)) 596 return true; 597 if (module != EVERYONE_MODULE) { 598 if (targets.contains(module)) 599 return true; 600 if (!module.isNamed() && targets.contains(ALL_UNNAMED_MODULE)) 601 return true; 602 } 603 } 604 return false; 605 } 606 607 /** 608 * Returns {@code true} if this module reflectively exports or opens the 609 * given package to the given module. 610 */ 611 private boolean isReflectivelyExportedOrOpen(String pn, Module other, boolean open) { 612 // exported or open to all modules 613 Map<String, Boolean> exports = ReflectionData.exports.get(this, EVERYONE_MODULE); 614 if (exports != null) { 615 Boolean b = exports.get(pn); 616 if (b != null) { 617 boolean isOpen = b.booleanValue(); 618 if (!open || isOpen) return true; 619 } 620 } 621 622 if (other != EVERYONE_MODULE) { 623 624 // exported or open to other 625 exports = ReflectionData.exports.get(this, other); 626 if (exports != null) { 627 Boolean b = exports.get(pn); 628 if (b != null) { 629 boolean isOpen = b.booleanValue(); 630 if (!open || isOpen) return true; 631 } 632 } 633 634 // other is an unnamed module && exported or open to all unnamed 635 if (!other.isNamed()) { 636 exports = ReflectionData.exports.get(this, ALL_UNNAMED_MODULE); 637 if (exports != null) { 638 Boolean b = exports.get(pn); 639 if (b != null) { 640 boolean isOpen = b.booleanValue(); 641 if (!open || isOpen) return true; 642 } 643 } 644 } 645 646 } 647 648 return false; 649 } 650 651 /** 652 * Returns {@code true} if this module reflectively exports the 653 * given package to the given module. 654 */ 655 boolean isReflectivelyExported(String pn, Module other) { 656 return isReflectivelyExportedOrOpen(pn, other, false); 657 } 658 659 /** 660 * Returns {@code true} if this module reflectively opens the 661 * given package to the given module. 662 */ 663 boolean isReflectivelyOpened(String pn, Module other) { 664 return isReflectivelyExportedOrOpen(pn, other, true); 665 } 666 667 668 /** 669 * If the caller's module is this module then update this module to export 670 * the given package to the given module. 671 * 672 * <p> This method has no effect if the package is already exported (or 673 * <em>open</em>) to the given module. </p> 674 * 675 * @apiNote As specified in section {@jvms 5.4.3} of the <cite>The Java 676 * Virtual Machine Specification </cite>, if an attempt to resolve a 677 * symbolic reference fails because of a linkage error, then subsequent 678 * attempts to resolve the reference always fail with the same error that 679 * was thrown as a result of the initial resolution attempt. 680 * 681 * @param pn 682 * The package name 683 * @param other 684 * The module 685 * 686 * @return this module 687 * 688 * @throws IllegalArgumentException 689 * If {@code pn} is {@code null}, or this is a named module and the 690 * package {@code pn} is not a package in this module 691 * @throws IllegalCallerException 692 * If this is a named module and the caller's module is not this 693 * module 694 * 695 * @jvms 5.4.3 Resolution 696 * @see #isExported(String,Module) 697 */ 698 @CallerSensitive 699 public Module addExports(String pn, Module other) { 700 if (pn == null) 701 throw new IllegalArgumentException("package is null"); 702 Objects.requireNonNull(other); 703 704 if (isNamed()) { 705 Module caller = getCallerModule(Reflection.getCallerClass()); 706 if (caller != this) { 707 throw new IllegalCallerException(caller + " != " + this); 708 } 709 implAddExportsOrOpens(pn, other, /*open*/false, /*syncVM*/true); 710 } 711 712 return this; 713 } 714 715 /** 716 * If this module has <em>opened</em> a package to at least the caller 717 * module then update this module to open the package to the given module. 718 * Opening a package with this method allows all types in the package, 719 * and all their members, not just public types and their public members, 720 * to be reflected on by the given module when using APIs that support 721 * private access or a way to bypass or suppress default Java language 722 * access control checks. 723 * 724 * <p> This method has no effect if the package is already <em>open</em> 725 * to the given module. </p> 726 * 727 * @apiNote This method can be used for cases where a <em>consumer 728 * module</em> uses a qualified opens to open a package to an <em>API 729 * module</em> but where the reflective access to the members of classes in 730 * the consumer module is delegated to code in another module. Code in the 731 * API module can use this method to open the package in the consumer module 732 * to the other module. 733 * 734 * @param pn 735 * The package name 736 * @param other 737 * The module 738 * 739 * @return this module 740 * 741 * @throws IllegalArgumentException 742 * If {@code pn} is {@code null}, or this is a named module and the 743 * package {@code pn} is not a package in this module 744 * @throws IllegalCallerException 745 * If this is a named module and this module has not opened the 746 * package to at least the caller's module 747 * 748 * @see #isOpen(String,Module) 749 * @see java.lang.reflect.AccessibleObject#setAccessible(boolean) 750 * @see java.lang.invoke.MethodHandles#privateLookupIn 751 */ 752 @CallerSensitive 753 public Module addOpens(String pn, Module other) { 754 if (pn == null) 755 throw new IllegalArgumentException("package is null"); 756 Objects.requireNonNull(other); 757 758 if (isNamed()) { 759 Module caller = getCallerModule(Reflection.getCallerClass()); 760 if (caller != this && (caller == null || !isOpen(pn, caller))) 761 throw new IllegalCallerException(pn + " is not open to " + caller); 762 implAddExportsOrOpens(pn, other, /*open*/true, /*syncVM*/true); 763 } 764 765 return this; 766 } 767 768 769 /** 770 * Updates this module to export a package unconditionally. 771 * 772 * @apiNote This method is for JDK tests only. 773 */ 774 void implAddExports(String pn) { 775 implAddExportsOrOpens(pn, Module.EVERYONE_MODULE, false, true); 776 } 777 778 /** 779 * Updates this module to export a package to another module. 780 * 781 * @apiNote Used by Instrumentation::redefineModule and --add-exports 782 */ 783 void implAddExports(String pn, Module other) { 784 implAddExportsOrOpens(pn, other, false, true); 785 } 786 787 /** 788 * Updates this module to export a package to all unnamed modules. 789 * 790 * @apiNote Used by the --add-exports command line option. 791 */ 792 void implAddExportsToAllUnnamed(String pn) { 793 implAddExportsOrOpens(pn, Module.ALL_UNNAMED_MODULE, false, true); 794 } 795 796 /** 797 * Updates this export to export a package unconditionally without 798 * notifying the VM. 799 * 800 * @apiNote This method is for VM white-box testing. 801 */ 802 void implAddExportsNoSync(String pn) { 803 implAddExportsOrOpens(pn.replace('/', '.'), Module.EVERYONE_MODULE, false, false); 804 } 805 806 /** 807 * Updates a module to export a package to another module without 808 * notifying the VM. 809 * 810 * @apiNote This method is for VM white-box testing. 811 */ 812 void implAddExportsNoSync(String pn, Module other) { 813 implAddExportsOrOpens(pn.replace('/', '.'), other, false, false); 814 } 815 816 /** 817 * Updates this module to open a package unconditionally. 818 * 819 * @apiNote This method is for JDK tests only. 820 */ 821 void implAddOpens(String pn) { 822 implAddExportsOrOpens(pn, Module.EVERYONE_MODULE, true, true); 823 } 824 825 /** 826 * Updates this module to open a package to another module. 827 * 828 * @apiNote Used by Instrumentation::redefineModule and --add-opens 829 */ 830 void implAddOpens(String pn, Module other) { 831 implAddExportsOrOpens(pn, other, true, true); 832 } 833 834 /** 835 * Updates this module to open a package to all unnamed modules. 836 * 837 * @apiNote Used by the --add-opens command line option. 838 */ 839 void implAddOpensToAllUnnamed(String pn) { 840 implAddExportsOrOpens(pn, Module.ALL_UNNAMED_MODULE, true, true); 841 } 842 843 /** 844 * Updates a module to export or open a module to another module. 845 * 846 * If {@code syncVM} is {@code true} then the VM is notified. 847 */ 848 private void implAddExportsOrOpens(String pn, 849 Module other, 850 boolean open, 851 boolean syncVM) { 852 Objects.requireNonNull(other); 853 Objects.requireNonNull(pn); 854 855 // all packages are open in unnamed, open, and automatic modules 856 if (!isNamed() || descriptor.isOpen() || descriptor.isAutomatic()) 857 return; 858 859 // check if the package is already exported/open to other 860 if (implIsExportedOrOpen(pn, other, open)) { 861 862 // if the package is exported/open for illegal access then we need 863 // to record that it has also been exported/opened reflectively so 864 // that the IllegalAccessLogger doesn't emit a warning. 865 boolean needToAdd = false; 866 if (!other.isNamed()) { 867 IllegalAccessLogger l = IllegalAccessLogger.illegalAccessLogger(); 868 if (l != null) { 869 if (open) { 870 needToAdd = l.isOpenForIllegalAccess(this, pn); 871 } else { 872 needToAdd = l.isExportedForIllegalAccess(this, pn); 873 } 874 } 875 } 876 if (!needToAdd) { 877 // nothing to do 878 return; 879 } 880 } 881 882 // can only export a package in the module 883 if (!descriptor.packages().contains(pn)) { 884 throw new IllegalArgumentException("package " + pn 885 + " not in contents"); 886 } 887 888 // update VM first, just in case it fails 889 if (syncVM) { 890 if (other == EVERYONE_MODULE) { 891 addExportsToAll0(this, pn); 892 } else if (other == ALL_UNNAMED_MODULE) { 893 addExportsToAllUnnamed0(this, pn); 894 } else { 895 addExports0(this, pn, other); 896 } 897 } 898 899 // add package name to exports if absent 900 Map<String, Boolean> map = ReflectionData.exports 901 .computeIfAbsent(this, other, 902 (m1, m2) -> new ConcurrentHashMap<>()); 903 if (open) { 904 map.put(pn, Boolean.TRUE); // may need to promote from FALSE to TRUE 905 } else { 906 map.putIfAbsent(pn, Boolean.FALSE); 907 } 908 } 909 910 /** 911 * Updates a module to open all packages in the given sets to all unnamed 912 * modules. 913 * 914 * @apiNote Used during startup to open packages for illegal access. 915 */ 916 void implAddOpensToAllUnnamed(Set<String> concealedPkgs, Set<String> exportedPkgs) { 917 if (jdk.internal.misc.VM.isModuleSystemInited()) { 918 throw new IllegalStateException("Module system already initialized"); 919 } 920 921 // replace this module's openPackages map with a new map that opens 922 // the packages to all unnamed modules. 923 Map<String, Set<Module>> openPackages = this.openPackages; 924 if (openPackages == null) { 925 openPackages = new HashMap<>((4 * (concealedPkgs.size() + exportedPkgs.size()) / 3) + 1); 926 } else { 927 openPackages = new HashMap<>(openPackages); 928 } 929 implAddOpensToAllUnnamed(concealedPkgs, openPackages); 930 implAddOpensToAllUnnamed(exportedPkgs, openPackages); 931 this.openPackages = openPackages; 932 } 933 934 private void implAddOpensToAllUnnamed(Set<String> pkgs, Map<String, Set<Module>> openPackages) { 935 for (String pn : pkgs) { 936 Set<Module> prev = openPackages.putIfAbsent(pn, ALL_UNNAMED_MODULE_SET); 937 if (prev != null) { 938 prev.add(ALL_UNNAMED_MODULE); 939 } 940 941 // update VM to export the package 942 addExportsToAllUnnamed0(this, pn); 943 } 944 } 945 946 // -- services -- 947 948 /** 949 * If the caller's module is this module then update this module to add a 950 * service dependence on the given service type. This method is intended 951 * for use by frameworks that invoke {@link java.util.ServiceLoader 952 * ServiceLoader} on behalf of other modules or where the framework is 953 * passed a reference to the service type by other code. This method is 954 * a no-op when invoked on an unnamed module or an automatic module. 955 * 956 * <p> This method does not cause {@link Configuration#resolveAndBind 957 * resolveAndBind} to be re-run. </p> 958 * 959 * @param service 960 * The service type 961 * 962 * @return this module 963 * 964 * @throws IllegalCallerException 965 * If this is a named module and the caller's module is not this 966 * module 967 * 968 * @see #canUse(Class) 969 * @see ModuleDescriptor#uses() 970 */ 971 @CallerSensitive 972 public Module addUses(Class<?> service) { 973 Objects.requireNonNull(service); 974 975 if (isNamed() && !descriptor.isAutomatic()) { 976 Module caller = getCallerModule(Reflection.getCallerClass()); 977 if (caller != this) { 978 throw new IllegalCallerException(caller + " != " + this); 979 } 980 implAddUses(service); 981 } 982 983 return this; 984 } 985 986 /** 987 * Update this module to add a service dependence on the given service 988 * type. 989 */ 990 void implAddUses(Class<?> service) { 991 if (!canUse(service)) { 992 ReflectionData.uses.putIfAbsent(this, service, Boolean.TRUE); 993 } 994 } 995 996 997 /** 998 * Indicates if this module has a service dependence on the given service 999 * type. This method always returns {@code true} when invoked on an unnamed 1000 * module or an automatic module. 1001 * 1002 * @param service 1003 * The service type 1004 * 1005 * @return {@code true} if this module uses service type {@code st} 1006 * 1007 * @see #addUses(Class) 1008 */ 1009 public boolean canUse(Class<?> service) { 1010 Objects.requireNonNull(service); 1011 1012 if (!isNamed()) 1013 return true; 1014 1015 if (descriptor.isAutomatic()) 1016 return true; 1017 1018 // uses was declared 1019 if (descriptor.uses().contains(service.getName())) 1020 return true; 1021 1022 // uses added via addUses 1023 return ReflectionData.uses.containsKeyPair(this, service); 1024 } 1025 1026 1027 1028 // -- packages -- 1029 1030 /** 1031 * Returns the set of package names for the packages in this module. 1032 * 1033 * <p> For named modules, the returned set contains an element for each 1034 * package in the module. </p> 1035 * 1036 * <p> For unnamed modules, this method is the equivalent to invoking the 1037 * {@link ClassLoader#getDefinedPackages() getDefinedPackages} method of 1038 * this module's class loader and returning the set of package names. </p> 1039 * 1040 * @return the set of the package names of the packages in this module 1041 */ 1042 public Set<String> getPackages() { 1043 if (isNamed()) { 1044 return descriptor.packages(); 1045 } else { 1046 // unnamed module 1047 Stream<Package> packages; 1048 if (loader == null) { 1049 packages = BootLoader.packages(); 1050 } else { 1051 packages = loader.packages(); 1052 } 1053 return packages.map(Package::getName).collect(Collectors.toSet()); 1054 } 1055 } 1056 1057 1058 // -- creating Module objects -- 1059 1060 /** 1061 * Defines all module in a configuration to the runtime. 1062 * 1063 * @return a map of module name to runtime {@code Module} 1064 * 1065 * @throws IllegalArgumentException 1066 * If the function maps a module to the null or platform class loader 1067 * @throws IllegalStateException 1068 * If the module cannot be defined to the VM or its packages overlap 1069 * with another module mapped to the same class loader 1070 */ 1071 static Map<String, Module> defineModules(Configuration cf, 1072 Function<String, ClassLoader> clf, 1073 ModuleLayer layer) 1074 { 1075 boolean isBootLayer = (ModuleLayer.boot() == null); 1076 1077 int numModules = cf.modules().size(); 1078 int cap = (int)(numModules / 0.75f + 1.0f); 1079 Map<String, Module> nameToModule = new HashMap<>(cap); 1080 1081 // to avoid repeated lookups and reduce iteration overhead, we create 1082 // arrays holding correlated information about each module. 1083 ResolvedModule[] resolvedModules = new ResolvedModule[numModules]; 1084 Module[] modules = new Module[numModules]; 1085 ClassLoader[] classLoaders = new ClassLoader[numModules]; 1086 1087 resolvedModules = cf.modules().toArray(resolvedModules); 1088 1089 // record that we want to bind the layer to non-boot and non-platform 1090 // module loaders as a final step 1091 HashSet<ClassLoader> toBindLoaders = new HashSet<>(4); 1092 boolean hasPlatformModules = false; 1093 1094 // map each module to a class loader 1095 ClassLoader pcl = ClassLoaders.platformClassLoader(); 1096 boolean isModuleLoaderMapper = ModuleLoaderMap.isBuiltinMapper(clf); 1097 1098 for (int index = 0; index < numModules; index++) { 1099 String name = resolvedModules[index].name(); 1100 ClassLoader loader = clf.apply(name); 1101 1102 if (loader == null || loader == pcl) { 1103 if (!isModuleLoaderMapper) { 1104 throw new IllegalArgumentException("loader can't be 'null'" 1105 + " or the platform class loader"); 1106 } 1107 hasPlatformModules = true; 1108 } else { 1109 toBindLoaders.add(loader); 1110 } 1111 1112 classLoaders[index] = loader; 1113 } 1114 1115 // define each module in the configuration to the VM 1116 for (int index = 0; index < numModules; index++) { 1117 ModuleReference mref = resolvedModules[index].reference(); 1118 ModuleDescriptor descriptor = mref.descriptor(); 1119 String name = descriptor.name(); 1120 ClassLoader loader = classLoaders[index]; 1121 Module m; 1122 if (loader == null && name.equals("java.base")) { 1123 // java.base is already defined to the VM 1124 m = Object.class.getModule(); 1125 } else { 1126 URI uri = mref.location().orElse(null); 1127 m = new Module(layer, loader, descriptor, uri); 1128 } 1129 nameToModule.put(name, m); 1130 modules[index] = m; 1131 } 1132 1133 // setup readability and exports/opens 1134 for (int index = 0; index < numModules; index++) { 1135 ResolvedModule resolvedModule = resolvedModules[index]; 1136 ModuleReference mref = resolvedModule.reference(); 1137 ModuleDescriptor descriptor = mref.descriptor(); 1138 Module m = modules[index]; 1139 1140 // reads 1141 Set<Module> reads = new HashSet<>(); 1142 1143 // name -> source Module when in parent layer 1144 Map<String, Module> nameToSource = Map.of(); 1145 1146 for (ResolvedModule other : resolvedModule.reads()) { 1147 Module m2 = null; 1148 if (other.configuration() == cf) { 1149 // this configuration 1150 m2 = nameToModule.get(other.name()); 1151 assert m2 != null; 1152 } else { 1153 // parent layer 1154 for (ModuleLayer parent: layer.parents()) { 1155 m2 = findModule(parent, other); 1156 if (m2 != null) 1157 break; 1158 } 1159 assert m2 != null; 1160 if (nameToSource.isEmpty()) 1161 nameToSource = new HashMap<>(); 1162 nameToSource.put(other.name(), m2); 1163 } 1164 reads.add(m2); 1165 1166 // update VM view 1167 addReads0(m, m2); 1168 } 1169 m.reads = reads; 1170 1171 // automatic modules read all unnamed modules 1172 if (descriptor.isAutomatic()) { 1173 m.implAddReads(ALL_UNNAMED_MODULE, true); 1174 } 1175 1176 // exports and opens, skipped for open and automatic 1177 if (!descriptor.isOpen() && !descriptor.isAutomatic()) { 1178 if (isBootLayer && descriptor.opens().isEmpty()) { 1179 // no open packages, no qualified exports to modules in parent layers 1180 initExports(m, nameToModule); 1181 } else { 1182 initExportsAndOpens(m, nameToSource, nameToModule, layer.parents()); 1183 } 1184 } 1185 } 1186 1187 // if there are modules defined to the boot or platform class loaders 1188 // then register the modules in the class loader's services catalog 1189 if (hasPlatformModules) { 1190 ServicesCatalog bootCatalog = BootLoader.getServicesCatalog(); 1191 ServicesCatalog pclCatalog = ServicesCatalog.getServicesCatalog(pcl); 1192 for (int index = 0; index < numModules; index++) { 1193 ResolvedModule resolvedModule = resolvedModules[index]; 1194 ModuleReference mref = resolvedModule.reference(); 1195 ModuleDescriptor descriptor = mref.descriptor(); 1196 if (!descriptor.provides().isEmpty()) { 1197 Module m = modules[index]; 1198 ClassLoader loader = classLoaders[index]; 1199 if (loader == null) { 1200 bootCatalog.register(m); 1201 } else if (loader == pcl) { 1202 pclCatalog.register(m); 1203 } 1204 } 1205 } 1206 } 1207 1208 // record that there is a layer with modules defined to the class loader 1209 for (ClassLoader loader : toBindLoaders) { 1210 layer.bindToLoader(loader); 1211 } 1212 1213 return nameToModule; 1214 } 1215 1216 /** 1217 * Find the runtime Module corresponding to the given ResolvedModule 1218 * in the given parent layer (or its parents). 1219 */ 1220 private static Module findModule(ModuleLayer parent, 1221 ResolvedModule resolvedModule) { 1222 Configuration cf = resolvedModule.configuration(); 1223 String dn = resolvedModule.name(); 1224 return parent.layers() 1225 .filter(l -> l.configuration() == cf) 1226 .findAny() 1227 .map(layer -> { 1228 Optional<Module> om = layer.findModule(dn); 1229 assert om.isPresent() : dn + " not found in layer"; 1230 Module m = om.get(); 1231 assert m.getLayer() == layer : m + " not in expected layer"; 1232 return m; 1233 }) 1234 .orElse(null); 1235 } 1236 1237 /** 1238 * Initialize/setup a module's exports. 1239 * 1240 * @param m the module 1241 * @param nameToModule map of module name to Module (for qualified exports) 1242 */ 1243 private static void initExports(Module m, Map<String, Module> nameToModule) { 1244 Map<String, Set<Module>> exportedPackages = new HashMap<>(); 1245 1246 for (Exports exports : m.getDescriptor().exports()) { 1247 String source = exports.source(); 1248 if (exports.isQualified()) { 1249 // qualified exports 1250 Set<Module> targets = new HashSet<>(); 1251 for (String target : exports.targets()) { 1252 Module m2 = nameToModule.get(target); 1253 if (m2 != null) { 1254 addExports0(m, source, m2); 1255 targets.add(m2); 1256 } 1257 } 1258 if (!targets.isEmpty()) { 1259 exportedPackages.put(source, targets); 1260 } 1261 } else { 1262 // unqualified exports 1263 addExportsToAll0(m, source); 1264 exportedPackages.put(source, EVERYONE_SET); 1265 } 1266 } 1267 1268 if (!exportedPackages.isEmpty()) 1269 m.exportedPackages = exportedPackages; 1270 } 1271 1272 /** 1273 * Initialize/setup a module's exports. 1274 * 1275 * @param m the module 1276 * @param nameToSource map of module name to Module for modules that m reads 1277 * @param nameToModule map of module name to Module for modules in the layer 1278 * under construction 1279 * @param parents the parent layers 1280 */ 1281 private static void initExportsAndOpens(Module m, 1282 Map<String, Module> nameToSource, 1283 Map<String, Module> nameToModule, 1284 List<ModuleLayer> parents) { 1285 ModuleDescriptor descriptor = m.getDescriptor(); 1286 Map<String, Set<Module>> openPackages = new HashMap<>(); 1287 Map<String, Set<Module>> exportedPackages = new HashMap<>(); 1288 1289 // process the open packages first 1290 for (Opens opens : descriptor.opens()) { 1291 String source = opens.source(); 1292 1293 if (opens.isQualified()) { 1294 // qualified opens 1295 Set<Module> targets = new HashSet<>(); 1296 for (String target : opens.targets()) { 1297 Module m2 = findModule(target, nameToSource, nameToModule, parents); 1298 if (m2 != null) { 1299 addExports0(m, source, m2); 1300 targets.add(m2); 1301 } 1302 } 1303 if (!targets.isEmpty()) { 1304 openPackages.put(source, targets); 1305 } 1306 } else { 1307 // unqualified opens 1308 addExportsToAll0(m, source); 1309 openPackages.put(source, EVERYONE_SET); 1310 } 1311 } 1312 1313 // next the exports, skipping exports when the package is open 1314 for (Exports exports : descriptor.exports()) { 1315 String source = exports.source(); 1316 1317 // skip export if package is already open to everyone 1318 Set<Module> openToTargets = openPackages.get(source); 1319 if (openToTargets != null && openToTargets.contains(EVERYONE_MODULE)) 1320 continue; 1321 1322 if (exports.isQualified()) { 1323 // qualified exports 1324 Set<Module> targets = new HashSet<>(); 1325 for (String target : exports.targets()) { 1326 Module m2 = findModule(target, nameToSource, nameToModule, parents); 1327 if (m2 != null) { 1328 // skip qualified export if already open to m2 1329 if (openToTargets == null || !openToTargets.contains(m2)) { 1330 addExports0(m, source, m2); 1331 targets.add(m2); 1332 } 1333 } 1334 } 1335 if (!targets.isEmpty()) { 1336 exportedPackages.put(source, targets); 1337 } 1338 } else { 1339 // unqualified exports 1340 addExportsToAll0(m, source); 1341 exportedPackages.put(source, EVERYONE_SET); 1342 } 1343 } 1344 1345 if (!openPackages.isEmpty()) 1346 m.openPackages = openPackages; 1347 if (!exportedPackages.isEmpty()) 1348 m.exportedPackages = exportedPackages; 1349 } 1350 1351 /** 1352 * Find the runtime Module with the given name. The module name is the 1353 * name of a target module in a qualified exports or opens directive. 1354 * 1355 * @param target The target module to find 1356 * @param nameToSource The modules in parent layers that are read 1357 * @param nameToModule The modules in the layer under construction 1358 * @param parents The parent layers 1359 */ 1360 private static Module findModule(String target, 1361 Map<String, Module> nameToSource, 1362 Map<String, Module> nameToModule, 1363 List<ModuleLayer> parents) { 1364 Module m = nameToSource.get(target); 1365 if (m == null) { 1366 m = nameToModule.get(target); 1367 if (m == null) { 1368 for (ModuleLayer parent : parents) { 1369 m = parent.findModule(target).orElse(null); 1370 if (m != null) break; 1371 } 1372 } 1373 } 1374 return m; 1375 } 1376 1377 1378 // -- annotations -- 1379 1380 /** 1381 * {@inheritDoc} 1382 * This method returns {@code null} when invoked on an unnamed module. 1383 * 1384 * <p> Note that any annotation returned by this method is a 1385 * declaration annotation. 1386 */ 1387 @Override 1388 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) { 1389 return moduleInfoClass().getDeclaredAnnotation(annotationClass); 1390 } 1391 1392 /** 1393 * {@inheritDoc} 1394 * This method returns an empty array when invoked on an unnamed module. 1395 * 1396 * <p> Note that any annotations returned by this method are 1397 * declaration annotations. 1398 */ 1399 @Override 1400 public Annotation[] getAnnotations() { 1401 return moduleInfoClass().getAnnotations(); 1402 } 1403 1404 /** 1405 * {@inheritDoc} 1406 * This method returns an empty array when invoked on an unnamed module. 1407 * 1408 * <p> Note that any annotations returned by this method are 1409 * declaration annotations. 1410 */ 1411 @Override 1412 public Annotation[] getDeclaredAnnotations() { 1413 return moduleInfoClass().getDeclaredAnnotations(); 1414 } 1415 1416 // cached class file with annotations 1417 private volatile Class<?> moduleInfoClass; 1418 1419 private Class<?> moduleInfoClass() { 1420 Class<?> clazz = this.moduleInfoClass; 1421 if (clazz != null) 1422 return clazz; 1423 1424 synchronized (this) { 1425 clazz = this.moduleInfoClass; 1426 if (clazz == null) { 1427 if (isNamed()) { 1428 PrivilegedAction<Class<?>> pa = this::loadModuleInfoClass; 1429 clazz = AccessController.doPrivileged(pa); 1430 } 1431 if (clazz == null) { 1432 class DummyModuleInfo { } 1433 clazz = DummyModuleInfo.class; 1434 } 1435 this.moduleInfoClass = clazz; 1436 } 1437 return clazz; 1438 } 1439 } 1440 1441 private Class<?> loadModuleInfoClass() { 1442 Class<?> clazz = null; 1443 try (InputStream in = getResourceAsStream("module-info.class")) { 1444 if (in != null) 1445 clazz = loadModuleInfoClass(in); 1446 } catch (Exception ignore) { } 1447 return clazz; 1448 } 1449 1450 /** 1451 * Loads module-info.class as a package-private interface in a class loader 1452 * that is a child of this module's class loader. 1453 */ 1454 private Class<?> loadModuleInfoClass(InputStream in) throws IOException { 1455 final String MODULE_INFO = "module-info"; 1456 1457 ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS 1458 + ClassWriter.COMPUTE_FRAMES); 1459 1460 ClassVisitor cv = new ClassVisitor(Opcodes.ASM7, cw) { 1461 @Override 1462 public void visit(int version, 1463 int access, 1464 String name, 1465 String signature, 1466 String superName, 1467 String[] interfaces) { 1468 cw.visit(version, 1469 Opcodes.ACC_INTERFACE 1470 + Opcodes.ACC_ABSTRACT 1471 + Opcodes.ACC_SYNTHETIC, 1472 MODULE_INFO, 1473 null, 1474 "java/lang/Object", 1475 null); 1476 } 1477 @Override 1478 public AnnotationVisitor visitAnnotation(String desc, boolean visible) { 1479 // keep annotations 1480 return super.visitAnnotation(desc, visible); 1481 } 1482 @Override 1483 public void visitAttribute(Attribute attr) { 1484 // drop non-annotation attributes 1485 } 1486 @Override 1487 public ModuleVisitor visitModule(String name, int flags, String version) { 1488 // drop Module attribute 1489 return null; 1490 } 1491 }; 1492 1493 ClassReader cr = new ClassReader(in); 1494 cr.accept(cv, 0); 1495 byte[] bytes = cw.toByteArray(); 1496 1497 ClassLoader cl = new ClassLoader(loader) { 1498 @Override 1499 protected Class<?> findClass(String cn)throws ClassNotFoundException { 1500 if (cn.equals(MODULE_INFO)) { 1501 return super.defineClass(cn, bytes, 0, bytes.length); 1502 } else { 1503 throw new ClassNotFoundException(cn); 1504 } 1505 } 1506 @Override 1507 protected Class<?> loadClass(String cn, boolean resolve) 1508 throws ClassNotFoundException 1509 { 1510 synchronized (getClassLoadingLock(cn)) { 1511 Class<?> c = findLoadedClass(cn); 1512 if (c == null) { 1513 if (cn.equals(MODULE_INFO)) { 1514 c = findClass(cn); 1515 } else { 1516 c = super.loadClass(cn, resolve); 1517 } 1518 } 1519 if (resolve) 1520 resolveClass(c); 1521 return c; 1522 } 1523 } 1524 }; 1525 1526 try { 1527 return cl.loadClass(MODULE_INFO); 1528 } catch (ClassNotFoundException e) { 1529 throw new InternalError(e); 1530 } 1531 } 1532 1533 1534 // -- misc -- 1535 1536 1537 /** 1538 * Returns an input stream for reading a resource in this module. 1539 * The {@code name} parameter is a {@code '/'}-separated path name that 1540 * identifies the resource. As with {@link Class#getResourceAsStream 1541 * Class.getResourceAsStream}, this method delegates to the module's class 1542 * loader {@link ClassLoader#findResource(String,String) 1543 * findResource(String,String)} method, invoking it with the module name 1544 * (or {@code null} when the module is unnamed) and the name of the 1545 * resource. If the resource name has a leading slash then it is dropped 1546 * before delegation. 1547 * 1548 * <p> A resource in a named module may be <em>encapsulated</em> so that 1549 * it cannot be located by code in other modules. Whether a resource can be 1550 * located or not is determined as follows: </p> 1551 * 1552 * <ul> 1553 * <li> If the resource name ends with "{@code .class}" then it is not 1554 * encapsulated. </li> 1555 * 1556 * <li> A <em>package name</em> is derived from the resource name. If 1557 * the package name is a {@linkplain #getPackages() package} in the 1558 * module then the resource can only be located by the caller of this 1559 * method when the package is {@linkplain #isOpen(String,Module) open} 1560 * to at least the caller's module. If the resource is not in a 1561 * package in the module then the resource is not encapsulated. </li> 1562 * </ul> 1563 * 1564 * <p> In the above, the <em>package name</em> for a resource is derived 1565 * from the subsequence of characters that precedes the last {@code '/'} in 1566 * the name and then replacing each {@code '/'} character in the subsequence 1567 * with {@code '.'}. A leading slash is ignored when deriving the package 1568 * name. As an example, the package name derived for a resource named 1569 * "{@code a/b/c/foo.properties}" is "{@code a.b.c}". A resource name 1570 * with the name "{@code META-INF/MANIFEST.MF}" is never encapsulated 1571 * because "{@code META-INF}" is not a legal package name. </p> 1572 * 1573 * <p> This method returns {@code null} if the resource is not in this 1574 * module, the resource is encapsulated and cannot be located by the caller, 1575 * or access to the resource is denied by the security manager. </p> 1576 * 1577 * @param name 1578 * The resource name 1579 * 1580 * @return An input stream for reading the resource or {@code null} 1581 * 1582 * @throws IOException 1583 * If an I/O error occurs 1584 * 1585 * @see Class#getResourceAsStream(String) 1586 */ 1587 @CallerSensitive 1588 public InputStream getResourceAsStream(String name) throws IOException { 1589 if (name.startsWith("/")) { 1590 name = name.substring(1); 1591 } 1592 1593 if (isNamed() && Resources.canEncapsulate(name)) { 1594 Module caller = getCallerModule(Reflection.getCallerClass()); 1595 if (caller != this && caller != Object.class.getModule()) { 1596 String pn = Resources.toPackageName(name); 1597 if (getPackages().contains(pn)) { 1598 if (caller == null && !isOpen(pn)) { 1599 // no caller, package not open 1600 return null; 1601 } 1602 if (!isOpen(pn, caller)) { 1603 // package not open to caller 1604 return null; 1605 } 1606 } 1607 } 1608 } 1609 1610 String mn = this.name; 1611 1612 // special-case built-in class loaders to avoid URL connection 1613 if (loader == null) { 1614 return BootLoader.findResourceAsStream(mn, name); 1615 } else if (loader instanceof BuiltinClassLoader) { 1616 return ((BuiltinClassLoader) loader).findResourceAsStream(mn, name); 1617 } 1618 1619 // locate resource in module 1620 URL url = loader.findResource(mn, name); 1621 if (url != null) { 1622 try { 1623 return url.openStream(); 1624 } catch (SecurityException e) { } 1625 } 1626 1627 return null; 1628 } 1629 1630 /** 1631 * Returns the string representation of this module. For a named module, 1632 * the representation is the string {@code "module"}, followed by a space, 1633 * and then the module name. For an unnamed module, the representation is 1634 * the string {@code "unnamed module"}, followed by a space, and then an 1635 * implementation specific string that identifies the unnamed module. 1636 * 1637 * @return The string representation of this module 1638 */ 1639 @Override 1640 public String toString() { 1641 if (isNamed()) { 1642 return "module " + name; 1643 } else { 1644 String id = Integer.toHexString(System.identityHashCode(this)); 1645 return "unnamed module @" + id; 1646 } 1647 } 1648 1649 /** 1650 * Returns the module that a given caller class is a member of. Returns 1651 * {@code null} if the caller is {@code null}. 1652 */ 1653 private Module getCallerModule(Class<?> caller) { 1654 return (caller != null) ? caller.getModule() : null; 1655 } 1656 1657 1658 // -- native methods -- 1659 1660 // JVM_DefineModule 1661 private static native void defineModule0(Module module, 1662 boolean isOpen, 1663 String version, 1664 String location, 1665 Object[] pns); 1666 1667 // JVM_AddReadsModule 1668 private static native void addReads0(Module from, Module to); 1669 1670 // JVM_AddModuleExports 1671 private static native void addExports0(Module from, String pn, Module to); 1672 1673 // JVM_AddModuleExportsToAll 1674 private static native void addExportsToAll0(Module from, String pn); 1675 1676 // JVM_AddModuleExportsToAllUnnamed 1677 private static native void addExportsToAllUnnamed0(Module from, String pn); 1678 }