Examples with SeekableByteChannel java.nio.channels.SeekableByteChannel used on opensource projects

Example 61 with SeekableByteChannel

use of java.nio.channels.SeekableByteChannel in project mycore by MyCoRe-Org.

the class MCRIView2Tools method readTile.

public static BufferedImage readTile(Path iviewFileRoot, ImageReader imageReader, int zoomLevel, int x, int y) throws IOException {
    String tileName = MessageFormat.format("{0}/{1}/{2}.jpg", zoomLevel, y, x);
    Path tile = iviewFileRoot.resolve(tileName);
    if (Files.exists(tile)) {
        try (SeekableByteChannel fileChannel = Files.newByteChannel(tile)) {
            ImageInputStream iis = ImageIO.createImageInputStream(fileChannel);
            if (iis == null) {
                throw new IOException("Could not acquire ImageInputStream from SeekableByteChannel: " + tile);
            }
            imageReader.setInput(iis, true);
            BufferedImage image = imageReader.read(0);
            imageReader.reset();
            iis.close();
            return image;
        }
    } else {
        throw new NoSuchFileException(iviewFileRoot.toString(), tileName, null);
    }
}

Example 62 with SeekableByteChannel

use of java.nio.channels.SeekableByteChannel in project graal by oracle.

the class FileSystemsTest method write.

private static void write(Path path, byte[] content, FileSystem fs) throws IOException {
    final Set<StandardOpenOption> options = EnumSet.of(StandardOpenOption.CREATE_NEW, StandardOpenOption.WRITE);
    try (SeekableByteChannel ch = fs.newByteChannel(path, options)) {
        ByteBuffer bb = ByteBuffer.wrap(content);
        ch.write(bb);
    }
}

Example 63 with SeekableByteChannel

use of java.nio.channels.SeekableByteChannel in project graal by oracle.

the class TruffleFile method readAllBytes.

/**
 * Reads a file content as bytes.
 *
 * @return the created <code>byte[]</code>
 * @throws IOException in case of IO error
 * @throws OutOfMemoryError if an array of a file size cannot be allocated
 * @throws SecurityException if the {@link FileSystem} denied the operation
 * @since 19.0
 */
@TruffleBoundary
public byte[] readAllBytes() throws IOException {
    try (SeekableByteChannel channel = newByteChannel(Collections.emptySet())) {
        long sizel = channel.size();
        if (sizel > MAX_BUFFER_SIZE) {
            throw new OutOfMemoryError("File size is too large.");
        }
        try (InputStream in = Channels.newInputStream(channel)) {
            int size = (int) sizel;
            byte[] buf = new byte[size];
            int read = 0;
            while (true) {
                int n;
                while ((n = in.read(buf, read, size - read)) > 0) {
                    read += n;
                }
                if (n < 0 || (n = in.read()) < 0) {
                    break;
                }
                if (size << 1 <= MAX_BUFFER_SIZE) {
                    size = Math.max(size << 1, BUFFER_SIZE);
                } else if (size == MAX_BUFFER_SIZE) {
                    throw new OutOfMemoryError("Required array size too large");
                } else {
                    size = MAX_BUFFER_SIZE;
                }
                buf = Arrays.copyOf(buf, size);
                buf[read++] = (byte) n;
            }
            return size == read ? buf : Arrays.copyOf(buf, read);
        }
    } catch (IOException | OutOfMemoryError | SecurityException e) {
        throw e;
    } catch (Throwable t) {
        throw wrapHostException(t);
    }
}

Example 64 with SeekableByteChannel

use of java.nio.channels.SeekableByteChannel in project graal by oracle.

the class NIOFileSystemTest method testNewByteChannel.

@Test
public void testNewByteChannel() throws IOException {
    expectException(() -> fs.newByteChannel(null, Collections.emptySet()).close(), NullPointerException.class);
    expectException(() -> fs.newByteChannel(file, null).close(), NullPointerException.class);
    expectException(() -> fs.newByteChannel(file, Collections.singleton(null)).close(), NullPointerException.class);
    Path targetRelative = workDir.resolve("testNewByteChannel");
    expectException(() -> fs.newByteChannel(targetRelative, EnumSet.of(StandardOpenOption.CREATE), (FileAttribute<?>[]) null).close(), NullPointerException.class);
    expectException(() -> fs.newByteChannel(targetRelative, EnumSet.of(StandardOpenOption.CREATE), new FileAttribute<?>[] { null }).close(), NullPointerException.class);
    expectException(() -> fs.newByteChannel(targetRelative, EnumSet.of(StandardOpenOption.CREATE), ATTR_UNKNOWN).close(), UnsupportedOperationException.class);
    expectException(() -> fs.newByteChannel(file, EnumSet.of(StandardOpenOption.WRITE, StandardOpenOption.CREATE_NEW)).close(), FileAlreadyExistsException.class);
    expectException(() -> fs.newByteChannel(targetRelative, Collections.emptySet()).close(), NoSuchFileException.class);
    try (SeekableByteChannel ch = fs.newByteChannel(targetRelative, EnumSet.of(StandardOpenOption.WRITE, StandardOpenOption.CREATE))) {
        Assert.assertTrue(ch instanceof FileChannel);
    }
    try (SeekableByteChannel ch = fs.newByteChannel(file, EnumSet.of(StandardOpenOption.READ))) {
        Assert.assertTrue(ch instanceof FileChannel);
    }
    try (SeekableByteChannel ch = fs.newByteChannel(fileRelative, EnumSet.of(StandardOpenOption.READ))) {
        Assert.assertTrue(ch instanceof FileChannel);
    }
}

Example 65 with SeekableByteChannel

use of java.nio.channels.SeekableByteChannel in project graal by oracle.

the class FileSystemProviderTest method testNewByteChannel.

@Test
public void testNewByteChannel() throws IOException {
    try (SeekableByteChannel ch = fs.newByteChannel(existingAbsolute, EnumSet.of(StandardOpenOption.READ))) {
        final ByteBuffer buffer = ByteBuffer.allocate(1024);
        ch.read(buffer);
        buffer.flip();
        Assert.assertEquals(getClass().getSimpleName(), StandardCharsets.UTF_8.decode(buffer).toString());
    }
    try (SeekableByteChannel ch = fs.newByteChannel(existingRelative, EnumSet.of(StandardOpenOption.READ))) {
        final ByteBuffer buffer = ByteBuffer.allocate(1024);
        ch.read(buffer);
        buffer.flip();
        Assert.assertEquals(getClass().getSimpleName(), StandardCharsets.UTF_8.decode(buffer).toString());
    }
}