test/jdk/java/nio/file/WatchService/FileTreeModifier.java

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/* @test
 * @bug 4313887 6838333
 * @summary Sanity test for JDK-specific FILE_TREE watch event modifier
 * @requires (os.family == "windows")
 * @library ..
 * @modules jdk.unsupported
 */

import java.nio.file.*;
import static java.nio.file.StandardWatchEventKinds.*;
import java.io.IOException;
import java.io.OutputStream;
import java.util.*;
import java.util.concurrent.*;
import static com.sun.nio.file.ExtendedWatchEventModifier.*;

public class FileTreeModifier {

    static void checkExpectedEvent(WatchService watcher,
                                   WatchEvent.Kind<?> expectedType,
                                   Object expectedContext)
    {
        WatchKey key;
        try {
            key = watcher.take();
        } catch (InterruptedException x) {
            // should not happen
            throw new RuntimeException(x);
        }
        WatchEvent<?> event = key.pollEvents().iterator().next();
        System.out.format("Event: type=%s, count=%d, context=%s\n",
            event.kind(), event.count(), event.context());
        if (event.kind() != expectedType)
            throw new RuntimeException("unexpected event");
        if (!expectedContext.equals(event.context()))
            throw new RuntimeException("unexpected context");
    }

    static void doTest(Path top) throws IOException {
        FileSystem fs = top.getFileSystem();
        WatchService watcher = fs.newWatchService();

        // create directories
        Path subdir = Files.createDirectories(top.resolve("a").resolve("b").resolve("c"));

        // Test ENTRY_CREATE with FILE_TREE modifier.

        WatchKey key = top.register(watcher,
            new WatchEvent.Kind<?>[]{ ENTRY_CREATE }, FILE_TREE);

        // create file in a/b/c and check we get create event
        Path file = Files.createFile(subdir.resolve("foo"));
        checkExpectedEvent(watcher, ENTRY_CREATE, top.relativize(file));
        key.reset();

        // Test ENTRY_DELETE with FILE_TREE modifier.

        WatchKey k = top.register(watcher,
            new WatchEvent.Kind<?>[]{ ENTRY_DELETE }, FILE_TREE);
        if (k != key)
            throw new RuntimeException("Existing key not returned");

        // delete a/b/c/foo and check we get delete event
        Files.delete(file);
        checkExpectedEvent(watcher, ENTRY_DELETE, top.relativize(file));
        key.reset();

        // Test changing registration to ENTRY_CREATE without modifier

        k = top.register(watcher, new WatchEvent.Kind<?>[]{ ENTRY_CREATE });
        if (k != key)
            throw new RuntimeException("Existing key not returned");

        // create a/b/c/foo
        Files.createFile(file);

        // check that key is not queued
        WatchKey nextKey;
        try {
            nextKey = watcher.poll(3, TimeUnit.SECONDS);
        } catch (InterruptedException e) {
            throw new RuntimeException();
        }
        if (nextKey != null)
            throw new RuntimeException("WatchKey not expected to be polled");

        // create bar and check we get create event
        file = Files.createFile(top.resolve("bar"));
        checkExpectedEvent(watcher, ENTRY_CREATE, top.relativize(file));
        key.reset();

        // Test changing registration to <all> with FILE_TREE modifier

        k = top.register(watcher,
            new WatchEvent.Kind<?>[]{ ENTRY_CREATE, ENTRY_DELETE, ENTRY_MODIFY },
            FILE_TREE);
        if (k != key)
            throw new RuntimeException("Existing key not returned");

        // modify bar and check we get modify event
        try (OutputStream out = Files.newOutputStream(file)) {
            out.write("Double shot expresso please".getBytes("UTF-8"));
        }
        checkExpectedEvent(watcher, ENTRY_MODIFY, top.relativize(file));
        key.reset();
    }


    public static void main(String[] args) throws IOException {
        Path dir = TestUtil.createTemporaryDirectory();
        try {
            doTest(dir);
        } finally {
            TestUtil.removeAll(dir);
        }
    }
}