1 /* 2 * Copyright (c) 2010, 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. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /* @test 25 * @bug 6907760 6929532 26 * @summary Tests WatchService behavior when lots of events are pending (use -Dseed=X to set PRNG seed) 27 * @library .. 28 * @library /test/lib 29 * @run main/timeout=180 LotsOfEvents 30 * @key randomness 31 */ 32 33 import java.io.IOException; 34 import java.io.OutputStream; 35 import java.nio.file.*; 36 import static java.nio.file.StandardWatchEventKinds.*; 37 import java.util.*; 38 import java.util.concurrent.TimeUnit; 39 import jdk.test.lib.RandomFactory; 40 41 public class LotsOfEvents { 42 43 private static final Random RAND = RandomFactory.getRandom(); 44 45 public static void main(String[] args) throws Exception { 46 Path dir = TestUtil.createTemporaryDirectory(); 47 try { 48 testOverflowEvent(dir); 49 testModifyEventsQueuing(dir); 50 } finally { 51 TestUtil.removeAll(dir); 52 } 53 } 54 55 /** 56 * Tests that OVERFLOW events are not retreived with other events. 57 */ 58 static void testOverflowEvent(Path dir) 59 throws IOException, InterruptedException 60 { 61 try (WatchService watcher = dir.getFileSystem().newWatchService()) { 62 dir.register(watcher, ENTRY_CREATE, ENTRY_DELETE); 63 64 // create a lot of files 65 int n = 1024; 66 Path[] files = new Path[n]; 67 for (int i=0; i<n; i++) { 68 files[i] = Files.createFile(dir.resolve("foo" + i)); 69 } 70 71 // give time for events to accumulate (improve chance of overflow) 72 Thread.sleep(1000); 73 74 // check that we see the create events (or overflow) 75 drainAndCheckOverflowEvents(dir, watcher, ENTRY_CREATE, n); 76 77 // delete the files 78 for (int i=0; i<n; i++) { 79 Files.delete(files[i]); 80 } 81 82 // give time for events to accumulate (improve chance of overflow) 83 Thread.sleep(1000); 84 85 // check that we see the delete events (or overflow) 86 drainAndCheckOverflowEvents(dir, watcher, ENTRY_DELETE, n); 87 } 88 } 89 90 static void drainAndCheckOverflowEvents(Path dir, 91 WatchService watcher, 92 WatchEvent.Kind<?> expectedKind, 93 int count) 94 throws IOException, InterruptedException 95 { 96 // wait for key to be signalled - the timeout is long to allow for 97 // polling implementations 98 WatchKey key = watcher.poll(15, TimeUnit.SECONDS); 99 if (key != null && count == 0) 100 throw new RuntimeException("Key was signalled (unexpected)"); 101 if (key == null && count > 0) 102 throw new RuntimeException("Key not signalled (unexpected)"); 103 104 int nread = 0; 105 boolean gotOverflow = false; 106 while (key != null) { 107 List<WatchEvent<?>> events = key.pollEvents(); 108 for (WatchEvent<?> event: events) { 109 WatchEvent.Kind<?> kind = event.kind(); 110 if (kind == expectedKind) { 111 // expected event kind 112 if (++nread > count) 113 throw new RuntimeException("More events than expected!!"); 114 } else if (kind == OVERFLOW) { 115 // overflow event should not be retrieved with other events 116 if (events.size() > 1) 117 throw new RuntimeException("Overflow retrieved with other events"); 118 gotOverflow = true; 119 } else { 120 throw new RuntimeException("Unexpected event '" + kind + "'"); 121 } 122 } 123 if (!key.reset()) 124 throw new RuntimeException("Key is no longer valid"); 125 key = watcher.poll(2, TimeUnit.SECONDS); 126 } 127 128 // check that all expected events were received or there was an overflow 129 if (nread < count && !gotOverflow) { 130 System.err.printf("Test directory %s contains %d files%n", 131 dir, Files.list(dir).count()); 132 133 long timeBeforePoll = System.nanoTime(); 134 key = watcher.poll(15, TimeUnit.SECONDS); 135 long timeAfterPoll = System.nanoTime(); 136 if (key == null) { 137 System.err.println("key still null after extra polling"); 138 } else { 139 List<WatchEvent<?>> events = key.pollEvents(); 140 System.err.printf("Retrieved key with %d events after %d ns%n", 141 events.size(), timeAfterPoll - timeBeforePoll); 142 } 143 144 throw new RuntimeException("Insufficient " 145 + expectedKind.name() + " events: expected " 146 + count + ", received " + nread); 147 } 148 } 149 150 /** 151 * Tests that check that ENTRY_MODIFY events are queued efficiently 152 */ 153 static void testModifyEventsQueuing(Path dir) 154 throws IOException, InterruptedException 155 { 156 // this test uses a random number of files 157 final int nfiles = 5 + RAND.nextInt(10); 158 DirectoryEntry[] entries = new DirectoryEntry[nfiles]; 159 for (int i=0; i<nfiles; i++) { 160 entries[i] = new DirectoryEntry(dir.resolve("foo" + i)); 161 162 // "some" of the files exist, some do not. 163 entries[i].deleteIfExists(); 164 if (RAND.nextBoolean()) 165 entries[i].create(); 166 } 167 168 try (WatchService watcher = dir.getFileSystem().newWatchService()) { 169 dir.register(watcher, ENTRY_CREATE, ENTRY_DELETE, ENTRY_MODIFY); 170 171 // do several rounds of noise and test 172 for (int round=0; round<10; round++) { 173 174 // make some noise!!! 175 for (int i=0; i<100; i++) { 176 DirectoryEntry entry = entries[RAND.nextInt(nfiles)]; 177 int action = RAND.nextInt(10); 178 switch (action) { 179 case 0 : entry.create(); break; 180 case 1 : entry.deleteIfExists(); break; 181 default: entry.modifyIfExists(); 182 } 183 } 184 185 // process events and ensure that we don't get repeated modify 186 // events for the same file. 187 WatchKey key = watcher.poll(15, TimeUnit.SECONDS); 188 while (key != null) { 189 Set<Path> modified = new HashSet<>(); 190 for (WatchEvent<?> event: key.pollEvents()) { 191 WatchEvent.Kind<?> kind = event.kind(); 192 Path file = (kind == OVERFLOW) ? null : (Path)event.context(); 193 if (kind == ENTRY_MODIFY) { 194 boolean added = modified.add(file); 195 if (!added) { 196 throw new RuntimeException( 197 "ENTRY_MODIFY events not queued efficiently"); 198 } 199 } else { 200 if (file != null) modified.remove(file); 201 } 202 } 203 if (!key.reset()) 204 throw new RuntimeException("Key is no longer valid"); 205 key = watcher.poll(2, TimeUnit.SECONDS); 206 } 207 } 208 } 209 } 210 211 static class DirectoryEntry { 212 private final Path file; 213 DirectoryEntry(Path file) { 214 this.file = file; 215 } 216 void create() throws IOException { 217 if (Files.notExists(file)) 218 Files.createFile(file); 219 220 } 221 void deleteIfExists() throws IOException { 222 Files.deleteIfExists(file); 223 } 224 void modifyIfExists() throws IOException { 225 if (Files.exists(file)) { 226 try (OutputStream out = Files.newOutputStream(file, StandardOpenOption.APPEND)) { 227 out.write("message".getBytes()); 228 } 229 } 230 } 231 } 232 233 }