1 /*
2 * Copyright (c) 2014, 2017, 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.internal.module;
27
28 import java.io.BufferedInputStream;
29 import java.io.BufferedReader;
30 import java.io.File;
31 import java.io.IOException;
32 import java.io.InputStream;
33 import java.io.InputStreamReader;
34 import java.io.UncheckedIOException;
35 import java.lang.module.FindException;
36 import java.lang.module.InvalidModuleDescriptorException;
37 import java.lang.module.ModuleDescriptor;
38 import java.lang.module.ModuleFinder;
39 import java.lang.module.ModuleReference;
40 import java.net.URI;
41 import java.nio.file.DirectoryStream;
42 import java.nio.file.Files;
43 import java.nio.file.NoSuchFileException;
44 import java.nio.file.Path;
45 import java.nio.file.Paths;
46 import java.nio.file.attribute.BasicFileAttributes;
47 import java.util.ArrayList;
48 import java.util.Collections;
49 import java.util.HashMap;
50 import java.util.List;
51 import java.util.Map;
52 import java.util.Objects;
53 import java.util.Optional;
54 import java.util.Set;
55 import java.util.jar.Attributes;
56 import java.util.jar.JarEntry;
57 import java.util.jar.JarFile;
58 import java.util.jar.Manifest;
59 import java.util.regex.Matcher;
60 import java.util.regex.Pattern;
61 import java.util.stream.Collectors;
62 import java.util.zip.ZipFile;
63
64 import jdk.internal.jmod.JmodFile;
65 import jdk.internal.jmod.JmodFile.Section;
66 import jdk.internal.perf.PerfCounter;
67 import jdk.internal.util.jar.VersionedStream;
68
69
70 /**
71 * A {@code ModuleFinder} that locates modules on the file system by searching
72 * a sequence of directories or packaged modules. The ModuleFinder can be
73 * created to work in either the run-time or link-time phases. In both cases it
74 * locates modular JAR and exploded modules. When created for link-time then it
75 * additionally locates modules in JMOD files. The ModuleFinder can also
76 * optionally patch any modules that it locates with a ModulePatcher.
77 */
78
79 public class ModulePath implements ModuleFinder {
80 private static final String MODULE_INFO = "module-info.class";
81
82 // the version to use for multi-release modular JARs
83 private final Runtime.Version releaseVersion;
84
85 // true for the link phase (supports modules packaged in JMOD format)
86 private final boolean isLinkPhase;
87
88 // for patching modules, can be null
89 private final ModulePatcher patcher;
90
91 // the entries on this module path
92 private final Path[] entries;
93 private int next;
94
95 // map of module name to module reference map for modules already located
96 private final Map<String, ModuleReference> cachedModules = new HashMap<>();
97
98
99 private ModulePath(Runtime.Version version,
100 boolean isLinkPhase,
101 ModulePatcher patcher,
102 Path... entries) {
103 this.releaseVersion = version;
104 this.isLinkPhase = isLinkPhase;
105 this.patcher = patcher;
106 this.entries = entries.clone();
107 for (Path entry : this.entries) {
108 Objects.requireNonNull(entry);
109 }
110 }
111
112 /**
113 * Returns a ModuleFinder that that locates modules on the file system by
114 * searching a sequence of directories and/or packaged modules. The modules
115 * may be patched by the given ModulePatcher.
116 */
117 public static ModuleFinder of(ModulePatcher patcher, Path... entries) {
118 return new ModulePath(JarFile.runtimeVersion(), false, patcher, entries);
119 }
120
121 /**
122 * Returns a ModuleFinder that that locates modules on the file system by
123 * searching a sequence of directories and/or packaged modules.
124 */
125 public static ModuleFinder of(Path... entries) {
126 return of((ModulePatcher)null, entries);
127 }
128
129 /**
130 * Returns a ModuleFinder that that locates modules on the file system by
131 * searching a sequence of directories and/or packaged modules.
132 *
133 * @param version The release version to use for multi-release JAR files
134 * @param isLinkPhase {@code true} if the link phase to locate JMOD files
135 */
136 public static ModuleFinder of(Runtime.Version version,
137 boolean isLinkPhase,
138 Path... entries) {
139 return new ModulePath(version, isLinkPhase, null, entries);
140 }
141
142
143 @Override
144 public Optional<ModuleReference> find(String name) {
145 Objects.requireNonNull(name);
146
147 // try cached modules
148 ModuleReference m = cachedModules.get(name);
149 if (m != null)
150 return Optional.of(m);
151
152 // the module may not have been encountered yet
153 while (hasNextEntry()) {
154 scanNextEntry();
155 m = cachedModules.get(name);
156 if (m != null)
157 return Optional.of(m);
158 }
159 return Optional.empty();
160 }
161
162 @Override
163 public Set<ModuleReference> findAll() {
164 // need to ensure that all entries have been scanned
165 while (hasNextEntry()) {
166 scanNextEntry();
167 }
168 return cachedModules.values().stream().collect(Collectors.toSet());
169 }
170
171 /**
172 * Returns {@code true} if there are additional entries to scan
173 */
174 private boolean hasNextEntry() {
175 return next < entries.length;
176 }
177
178 /**
179 * Scans the next entry on the module path. A no-op if all entries have
180 * already been scanned.
181 *
182 * @throws FindException if an error occurs scanning the next entry
183 */
184 private void scanNextEntry() {
185 if (hasNextEntry()) {
186
187 long t0 = System.nanoTime();
188
189 Path entry = entries[next];
190 Map<String, ModuleReference> modules = scan(entry);
191 next++;
192
193 // update cache, ignoring duplicates
194 int initialSize = cachedModules.size();
195 for (Map.Entry<String, ModuleReference> e : modules.entrySet()) {
196 cachedModules.putIfAbsent(e.getKey(), e.getValue());
197 }
198
199 // update counters
200 int added = cachedModules.size() - initialSize;
201 moduleCount.add(added);
202
203 scanTime.addElapsedTimeFrom(t0);
204 }
205 }
206
207
208 /**
209 * Scan the given module path entry. If the entry is a directory then it is
210 * a directory of modules or an exploded module. If the entry is a regular
211 * file then it is assumed to be a packaged module.
212 *
213 * @throws FindException if an error occurs scanning the entry
214 */
215 private Map<String, ModuleReference> scan(Path entry) {
216
217 BasicFileAttributes attrs;
218 try {
219 attrs = Files.readAttributes(entry, BasicFileAttributes.class);
220 } catch (NoSuchFileException e) {
221 return Collections.emptyMap();
222 } catch (IOException ioe) {
223 throw new FindException(ioe);
224 }
225
226 try {
227
228 if (attrs.isDirectory()) {
229 Path mi = entry.resolve(MODULE_INFO);
230 if (!Files.exists(mi)) {
231 // assume a directory of modules
232 return scanDirectory(entry);
233 }
234 }
235
236 // packaged or exploded module
237 ModuleReference mref = readModule(entry, attrs);
238 if (mref != null) {
239 String name = mref.descriptor().name();
240 return Collections.singletonMap(name, mref);
241 }
242
243 // not recognized
244 String msg;
245 if (!isLinkPhase && entry.toString().endsWith(".jmod")) {
246 msg = "JMOD format not supported at execution time";
247 } else {
248 msg = "Module format not recognized";
249 }
250 throw new FindException(msg + ": " + entry);
251
252 } catch (IOException ioe) {
253 throw new FindException(ioe);
254 }
255 }
256
257
258 /**
259 * Scans the given directory for packaged or exploded modules.
260 *
261 * @return a map of module name to ModuleReference for the modules found
262 * in the directory
263 *
264 * @throws IOException if an I/O error occurs
265 * @throws FindException if an error occurs scanning the entry or the
266 * directory contains two or more modules with the same name
267 */
268 private Map<String, ModuleReference> scanDirectory(Path dir)
269 throws IOException
270 {
271 // The map of name -> mref of modules found in this directory.
272 Map<String, ModuleReference> nameToReference = new HashMap<>();
273
274 try (DirectoryStream<Path> stream = Files.newDirectoryStream(dir)) {
275 for (Path entry : stream) {
276 BasicFileAttributes attrs;
277 try {
278 attrs = Files.readAttributes(entry, BasicFileAttributes.class);
279 } catch (NoSuchFileException ignore) {
280 // file has been removed or moved, ignore for now
281 continue;
282 }
283
284 ModuleReference mref = readModule(entry, attrs);
285
286 // module found
287 if (mref != null) {
288 // can have at most one version of a module in the directory
289 String name = mref.descriptor().name();
290 ModuleReference previous = nameToReference.put(name, mref);
291 if (previous != null) {
292 String fn1 = fileName(mref);
293 String fn2 = fileName(previous);
294 throw new FindException("Two versions of module "
295 + name + " found in " + dir
296 + " (" + fn1 + " and " + fn2 + ")");
297 }
298 }
299 }
300 }
301
302 return nameToReference;
303 }
304
305
306 /**
307 * Reads a packaged or exploded module, returning a {@code ModuleReference}
308 * to the module. Returns {@code null} if the entry is not recognized.
309 *
310 * @throws IOException if an I/O error occurs
311 * @throws FindException if an error occurs parsing its module descriptor
312 */
313 private ModuleReference readModule(Path entry, BasicFileAttributes attrs)
314 throws IOException
315 {
316 try {
317
318 if (attrs.isDirectory()) {
319 return readExplodedModule(entry); // may return null
320 } else {
321 String fn = entry.getFileName().toString();
322 if (attrs.isRegularFile()) {
323 if (fn.endsWith(".jar")) {
324 return readJar(entry);
325 } else if (isLinkPhase && fn.endsWith(".jmod")) {
326 return readJMod(entry);
327 }
328 }
329 return null;
330 }
331
332 } catch (InvalidModuleDescriptorException e) {
333 throw new FindException("Error reading module: " + entry, e);
334 }
335 }
336
337
338 /**
339 * Returns a string with the file name of the module if possible.
340 * If the module location is not a file URI then return the URI
341 * as a string.
342 */
343 private String fileName(ModuleReference mref) {
344 URI uri = mref.location().orElse(null);
345 if (uri != null) {
346 if (uri.getScheme().equalsIgnoreCase("file")) {
347 Path file = Paths.get(uri);
348 return file.getFileName().toString();
349 } else {
350 return uri.toString();
351 }
352 } else {
353 return "<unknown>";
354 }
355 }
356
357 // -- JMOD files --
358
359 private Set<String> jmodPackages(JmodFile jf) {
360 return jf.stream()
361 .filter(e -> e.section() == Section.CLASSES)
362 .map(JmodFile.Entry::name)
363 .map(this::toPackageName)
364 .flatMap(Optional::stream)
365 .collect(Collectors.toSet());
366 }
367
368 /**
369 * Returns a {@code ModuleReference} to a module in JMOD file on the
370 * file system.
371 *
372 * @throws IOException
373 * @throws InvalidModuleDescriptorException
374 */
375 private ModuleReference readJMod(Path file) throws IOException {
376 try (JmodFile jf = new JmodFile(file)) {
377 ModuleInfo.Attributes attrs;
378 try (InputStream in = jf.getInputStream(Section.CLASSES, MODULE_INFO)) {
379 attrs = ModuleInfo.read(in, () -> jmodPackages(jf));
380 }
381 return ModuleReferences.newJModModule(attrs, file);
382 }
383 }
384
385
386 // -- JAR files --
387
388 private static final String SERVICES_PREFIX = "META-INF/services/";
389
390 /**
391 * Returns the service type corresponding to the name of a services
392 * configuration file if it is a legal type name.
393 *
394 * For example, if called with "META-INF/services/p.S" then this method
395 * returns a container with the value "p.S".
396 */
397 private Optional<String> toServiceName(String cf) {
398 assert cf.startsWith(SERVICES_PREFIX);
399 int index = cf.lastIndexOf("/") + 1;
400 if (index < cf.length()) {
401 String prefix = cf.substring(0, index);
402 if (prefix.equals(SERVICES_PREFIX)) {
403 String sn = cf.substring(index);
404 if (Checks.isClassName(sn))
405 return Optional.of(sn);
406 }
407 }
408 return Optional.empty();
409 }
410
411 /**
412 * Reads the next line from the given reader and trims it of comments and
413 * leading/trailing white space.
414 *
415 * Returns null if the reader is at EOF.
416 */
417 private String nextLine(BufferedReader reader) throws IOException {
418 String ln = reader.readLine();
419 if (ln != null) {
420 int ci = ln.indexOf('#');
421 if (ci >= 0)
422 ln = ln.substring(0, ci);
423 ln = ln.trim();
424 }
425 return ln;
426 }
427
428 /**
429 * Treat the given JAR file as a module as follows:
430 *
431 * 1. The module name (and optionally the version) is derived from the file
432 * name of the JAR file
433 * 2. All packages are derived from the .class files in the JAR file
434 * 3. The contents of any META-INF/services configuration files are mapped
435 * to "provides" declarations
436 * 4. The Main-Class attribute in the main attributes of the JAR manifest
437 * is mapped to the module descriptor mainClass
438 */
439 private ModuleDescriptor deriveModuleDescriptor(JarFile jf)
440 throws IOException
441 {
442 // Derive module name and version from JAR file name
443
444 String fn = jf.getName();
445 int i = fn.lastIndexOf(File.separator);
446 if (i != -1)
447 fn = fn.substring(i+1);
448
449 // drop .jar
450 String mn = fn.substring(0, fn.length()-4);
451 String vs = null;
452
453 // find first occurrence of -${NUMBER}. or -${NUMBER}$
454 Matcher matcher = Patterns.DASH_VERSION.matcher(mn);
455 if (matcher.find()) {
456 int start = matcher.start();
457
458 // attempt to parse the tail as a version string
459 try {
460 String tail = mn.substring(start+1);
461 ModuleDescriptor.Version.parse(tail);
462 vs = tail;
463 } catch (IllegalArgumentException ignore) { }
464
465 mn = mn.substring(0, start);
466 }
467
468 // finally clean up the module name
469 mn = cleanModuleName(mn);
470
471 // Builder throws IAE if module name is empty or invalid
472 ModuleDescriptor.Builder builder = ModuleDescriptor.newAutomaticModule(mn);
473 if (vs != null)
474 builder.version(vs);
475
476 // scan the names of the entries in the JAR file
477 Map<Boolean, Set<String>> map = VersionedStream.stream(jf)
478 .filter(e -> !e.isDirectory())
479 .map(JarEntry::getName)
480 .filter(e -> (e.endsWith(".class") ^ e.startsWith(SERVICES_PREFIX)))
481 .collect(Collectors.partitioningBy(e -> e.startsWith(SERVICES_PREFIX),
482 Collectors.toSet()));
483
484 Set<String> classFiles = map.get(Boolean.FALSE);
485 Set<String> configFiles = map.get(Boolean.TRUE);
486
487 // the packages containing class files
488 Set<String> packages = classFiles.stream()
489 .map(this::toPackageName)
490 .flatMap(Optional::stream)
491 .distinct()
492 .collect(Collectors.toSet());
493
494 // all packages are exported and open
495 builder.packages(packages);
496
497 // map names of service configuration files to service names
498 Set<String> serviceNames = configFiles.stream()
499 .map(this::toServiceName)
500 .flatMap(Optional::stream)
501 .collect(Collectors.toSet());
502
503 // parse each service configuration file
504 for (String sn : serviceNames) {
505 JarEntry entry = jf.getJarEntry(SERVICES_PREFIX + sn);
506 List<String> providerClasses = new ArrayList<>();
507 try (InputStream in = jf.getInputStream(entry)) {
508 BufferedReader reader
509 = new BufferedReader(new InputStreamReader(in, "UTF-8"));
510 String cn;
511 while ((cn = nextLine(reader)) != null) {
512 if (cn.length() > 0) {
513 String pn = packageName(cn);
514 if (!packages.contains(pn)) {
515 String msg = "Provider class " + cn + " not in module";
516 throw new InvalidModuleDescriptorException(msg);
517 }
518 providerClasses.add(cn);
519 }
520 }
521 }
522 if (!providerClasses.isEmpty())
523 builder.provides(sn, providerClasses);
524 }
525
526 // Main-Class attribute if it exists
527 Manifest man = jf.getManifest();
528 if (man != null) {
529 Attributes attrs = man.getMainAttributes();
530 String mainClass = attrs.getValue(Attributes.Name.MAIN_CLASS);
531 if (mainClass != null) {
532 mainClass = mainClass.replace("/", ".");
533 String pn = packageName(mainClass);
534 if (!packages.contains(pn)) {
535 String msg = "Main-Class " + mainClass + " not in module";
536 throw new InvalidModuleDescriptorException(msg);
537 }
538 builder.mainClass(mainClass);
539 }
540 }
541
542 return builder.build();
543 }
544
545 /**
546 * Patterns used to derive the module name from a JAR file name.
547 */
548 private static class Patterns {
549 static final Pattern DASH_VERSION = Pattern.compile("-(\\d+(\\.|$))");
550 static final Pattern TRAILING_VERSION = Pattern.compile("(\\.|\\d)*$");
551 static final Pattern NON_ALPHANUM = Pattern.compile("[^A-Za-z0-9]");
552 static final Pattern REPEATING_DOTS = Pattern.compile("(\\.)(\\1)+");
553 static final Pattern LEADING_DOTS = Pattern.compile("^\\.");
554 static final Pattern TRAILING_DOTS = Pattern.compile("\\.$");
555 }
556
557 /**
558 * Clean up candidate module name derived from a JAR file name.
559 */
560 private static String cleanModuleName(String mn) {
561 // drop trailing version from name
562 mn = Patterns.TRAILING_VERSION.matcher(mn).replaceAll("");
563
564 // replace non-alphanumeric
565 mn = Patterns.NON_ALPHANUM.matcher(mn).replaceAll(".");
566
567 // collapse repeating dots
568 mn = Patterns.REPEATING_DOTS.matcher(mn).replaceAll(".");
569
570 // drop leading dots
571 if (mn.length() > 0 && mn.charAt(0) == '.')
572 mn = Patterns.LEADING_DOTS.matcher(mn).replaceAll("");
573
574 // drop trailing dots
575 int len = mn.length();
576 if (len > 0 && mn.charAt(len-1) == '.')
577 mn = Patterns.TRAILING_DOTS.matcher(mn).replaceAll("");
578
579 return mn;
580 }
581
582 private Set<String> jarPackages(JarFile jf) {
583 return VersionedStream.stream(jf)
584 .filter(e -> !e.isDirectory())
585 .map(JarEntry::getName)
586 .map(this::toPackageName)
587 .flatMap(Optional::stream)
588 .collect(Collectors.toSet());
589 }
590
591 /**
592 * Returns a {@code ModuleReference} to a module in modular JAR file on
593 * the file system.
594 *
595 * @throws IOException
596 * @throws FindException
597 * @throws InvalidModuleDescriptorException
598 */
599 private ModuleReference readJar(Path file) throws IOException {
600 try (JarFile jf = new JarFile(file.toFile(),
601 true, // verify
602 ZipFile.OPEN_READ,
603 releaseVersion))
604 {
605 ModuleInfo.Attributes attrs;
606 JarEntry entry = jf.getJarEntry(MODULE_INFO);
607 if (entry == null) {
608
609 // no module-info.class so treat it as automatic module
610 try {
611 ModuleDescriptor md = deriveModuleDescriptor(jf);
612 attrs = new ModuleInfo.Attributes(md, null, null, null);
613 } catch (RuntimeException e) {
614 throw new FindException("Unable to derive module descriptor for "
615 + jf.getName(), e);
616 }
617
618 } else {
619 attrs = ModuleInfo.read(jf.getInputStream(entry),
620 () -> jarPackages(jf));
621 }
622
623 return ModuleReferences.newJarModule(attrs, patcher, file);
624 }
625 }
626
627
628 // -- exploded directories --
629
630 private Set<String> explodedPackages(Path dir) {
631 try {
632 return Files.find(dir, Integer.MAX_VALUE,
633 ((path, attrs) -> attrs.isRegularFile()))
634 .map(path -> dir.relativize(path))
635 .map(this::toPackageName)
636 .flatMap(Optional::stream)
637 .collect(Collectors.toSet());
638 } catch (IOException x) {
639 throw new UncheckedIOException(x);
640 }
641 }
642
643 /**
644 * Returns a {@code ModuleReference} to an exploded module on the file
645 * system or {@code null} if {@code module-info.class} not found.
646 *
647 * @throws IOException
648 * @throws InvalidModuleDescriptorException
649 */
650 private ModuleReference readExplodedModule(Path dir) throws IOException {
651 Path mi = dir.resolve(MODULE_INFO);
652 ModuleInfo.Attributes attrs;
653 try (InputStream in = Files.newInputStream(mi)) {
654 attrs = ModuleInfo.read(new BufferedInputStream(in),
655 () -> explodedPackages(dir));
656 } catch (NoSuchFileException e) {
657 // for now
658 return null;
659 }
660 return ModuleReferences.newExplodedModule(attrs, patcher, dir);
661 }
662
663 /**
664 * Maps a type name to its package name.
665 */
666 private static String packageName(String cn) {
667 int index = cn.lastIndexOf('.');
668 return (index == -1) ? "" : cn.substring(0, index);
669 }
670
671 /**
672 * Maps the name of an entry in a JAR or ZIP file to a package name.
673 *
674 * @throws InvalidModuleDescriptorException if the name is a class file in
675 * the top-level directory of the JAR/ZIP file (and it's not
676 * module-info.class)
677 */
678 private Optional<String> toPackageName(String name) {
679 assert !name.endsWith("/");
680 int index = name.lastIndexOf("/");
681 if (index == -1) {
682 if (name.endsWith(".class") && !name.equals(MODULE_INFO)) {
683 String msg = name + " found in top-level directory"
684 + " (unnamed package not allowed in module)";
685 throw new InvalidModuleDescriptorException(msg);
686 }
687 return Optional.empty();
688 }
689
690 String pn = name.substring(0, index).replace('/', '.');
691 if (Checks.isPackageName(pn)) {
692 return Optional.of(pn);
693 } else {
694 // not a valid package name
695 return Optional.empty();
696 }
697 }
698
699 /**
700 * Maps the relative path of an entry in an exploded module to a package
701 * name.
702 *
703 * @throws InvalidModuleDescriptorException if the name is a class file in
704 * the top-level directory (and it's not module-info.class)
705 */
706 private Optional<String> toPackageName(Path file) {
707 assert file.getRoot() == null;
708
709 Path parent = file.getParent();
710 if (parent == null) {
711 String name = file.toString();
712 if (name.endsWith(".class") && !name.equals(MODULE_INFO)) {
713 String msg = name + " found in top-level directory"
714 + " (unnamed package not allowed in module)";
715 throw new InvalidModuleDescriptorException(msg);
716 }
717 return Optional.empty();
718 }
719
720 String pn = parent.toString().replace(File.separatorChar, '.');
721 if (Checks.isPackageName(pn)) {
722 return Optional.of(pn);
723 } else {
724 // not a valid package name
725 return Optional.empty();
726 }
727 }
728
729 private static final PerfCounter scanTime
730 = PerfCounter.newPerfCounter("jdk.module.finder.modulepath.scanTime");
731 private static final PerfCounter moduleCount
732 = PerfCounter.newPerfCounter("jdk.module.finder.modulepath.modules");
733 }