java.nio.channels.FileChannel Java Examples

@Test
public void testMaxScan() throws Exception {
    int size = (1 << 16) + 22;
    File maxscan = testSupport.getFile("maxscan.jar");
    FileChannel ch = testSupport.getChannel(maxscan, false);
    ByteBuffer bb = ByteBuffer.allocate(1);
    bb.put((byte)0);
    bb.flip();
    ch.write(bb, size -1);

    Assert.assertFalse(ZipCompletionScanner.isCompleteZip(maxscan));

    File maxscanplus = testSupport.getFile("maxscanplus.jar");
    ch = testSupport.getChannel(maxscanplus, false);
    bb.flip();
    ch.write(bb, size);

    Assert.assertFalse(ZipCompletionScanner.isCompleteZip(maxscanplus));

    File maxscanminus = testSupport.getFile("maxscanminus.jar");
    ch = testSupport.getChannel(maxscanminus, false);
    bb.flip();
    ch.write(bb, size - 2);

    Assert.assertFalse(ZipCompletionScanner.isCompleteZip(maxscanplus));
}
 

/**
 * Creates the specified <code>toFile</code> as a byte for byte copy of the
 * <code>fromFile</code>. If <code>toFile</code> already exists, then it
 * will be replaced with a copy of <code>fromFile</code>. The name and path
 * of <code>toFile</code> will be that of <code>toFile</code>.<br/>
 * <br/>
 * <i> Note: <code>fromFile</code> and <code>toFile</code> will be closed by
 * this function.</i>
 * 
 * @param fromFile
 *            - FileInputStream for the file to copy from.
 * @param toFile
 *            - FileInputStream for the file to copy to.
 */
public static void copyFile(FileInputStream fromFile, FileOutputStream toFile) throws IOException {
    FileChannel fromChannel = null;
    FileChannel toChannel = null;
    try {
        fromChannel = fromFile.getChannel();
        toChannel = toFile.getChannel();
        fromChannel.transferTo(0, fromChannel.size(), toChannel);
    } finally {
        try {
            if (fromChannel != null) {
                fromChannel.close();
            }
        } finally {
            if (toChannel != null) {
                toChannel.close();
            }
        }
    }
}
 

private static void nioCopyFile(File source, File target, boolean replaceIfExists)
    throws IOException {
  if (!target.createNewFile()) // atomic
  {
    if (target.exists() && !replaceIfExists) {
      throw new IOException(
          String.format("File '%s' already exists. ", target.getAbsolutePath()));
    }
  }

  try (FileInputStream sourceStream = new FileInputStream(source);
      FileOutputStream targetStream = new FileOutputStream(target);
      FileChannel sourceChannel = sourceStream.getChannel();
      FileChannel targetChannel = targetStream.getChannel()) {

    final long size = sourceChannel.size();
    long transferred = 0L;
    while (transferred < size) {
      transferred += targetChannel.transferFrom(sourceChannel, transferred, (size - transferred));
    }
  }
}
 

private static <T> T withBlockingLock(File dexDir, File sourceApk, RunnableIO<T> r) throws IOException {
    final long currentCrc = getZipCrc(sourceApk);
    File lockFile = new File(dexDir, LOCK_FILE);
    RandomAccessFile lockRaf = new RandomAccessFile(lockFile, "rw");
    FileChannel lockChannel = null;
    FileLock cacheLock = null;
    try {
        lockChannel = lockRaf.getChannel();
        Log.v(TAG, "Waiting for lock on: " + lockFile.getAbsolutePath());
        cacheLock = lockChannel.lock();
        Log.v(TAG, "Locked " + lockFile.getPath());
        long l = lockRaf.length() >= (Long.SIZE / 8) ? lockRaf.readLong() : 0;
        long c = lockRaf.length() >= 2 * (Long.SIZE / 8) ? lockRaf.readLong() : 0;
        return r.run(c != currentCrc || l != getTimeStamp(sourceApk));
    } finally {
        lockRaf.seek(0);
        lockRaf.writeLong(getTimeStamp(sourceApk));
        lockRaf.writeLong(currentCrc);
        if (cacheLock != null)
            cacheLock.release();
        if (lockChannel != null)
            lockChannel.close();
        lockRaf.close();
        Log.v(TAG, "Unlocked " + lockFile.getPath());
    }
}
 

@Test
public void testGetBufferReallocate() throws Exception {
  BufferedFile instance;
  int fileSize = 64;
  String filename = "bytes64";
  byte[] bytes = fileData(fileSize);
  fileSystem.addFile(filename, bytes);
  FileChannel file = fileSystem.getInputChannel(filename);
  int regionOff = 5;
  int regionSize = 50;
  int maxAlloc = 20;
  int cacheOff = regionOff + 5;
  instance = new BufferedFile(file, regionOff, regionSize, maxAlloc);
  instance.getBuffer(cacheOff, maxAlloc);
  assertCase("Realloc after", instance, cacheOff + maxAlloc, maxAlloc, maxAlloc, maxAlloc);
  assertCase("Realloc before", instance, cacheOff, maxAlloc, maxAlloc, maxAlloc);
  assertCase("Realloc just after", instance, cacheOff + 5, maxAlloc, maxAlloc, maxAlloc);
  assertCase("Realloc just before", instance, cacheOff, maxAlloc, maxAlloc, maxAlloc);
  assertCase("Realloc supersize", instance, cacheOff, maxAlloc + 5, maxAlloc + 5, maxAlloc + 5);
}
 

@Test
public void readPrematureEndOfFile2() throws Exception {
	final FileChannel fc = tmpFileChannel();
	final Buffer buffer = createTestBuffer();
	final MemorySegment readBuffer = MemorySegmentFactory.allocateUnpooledOffHeapMemory(buffer.getSize(), null);

	BufferReaderWriterUtil.writeToByteChannel(fc, buffer, BufferReaderWriterUtil.allocatedWriteBufferArray());
	fc.truncate(2); // less than a header size
	fc.position(0);

	try {
		BufferReaderWriterUtil.readFromByteChannel(
				fc, BufferReaderWriterUtil.allocatedHeaderBuffer(), readBuffer, FreeingBufferRecycler.INSTANCE);
		fail();
	}
	catch (IOException e) {
		// expected
	}
}
 

/**
 * @param factory Factory to produce FileIO access.
 * @param from Copy from file.
 * @param to Copy data to file.
 * @param length Number of bytes to copy from beginning.
 */
static void copy(FileIOFactory factory, File from, File to, long length) {
    try (FileIO src = factory.create(from, READ);
         FileChannel dest = new FileOutputStream(to).getChannel()) {
        if (src.size() < length) {
            throw new IgniteException("The source file to copy has to enough length " +
                "[expected=" + length + ", actual=" + src.size() + ']');
        }

        src.position(0);

        long written = 0;

        while (written < length)
            written += src.transferTo(written, length - written, dest);
    }
    catch (IOException e) {
        throw new IgniteException(e);
    }
}
 

/**
 * Creates FLV reader from file channel.
 *
 * @param channel
 *            file channel
 * @throws IOException
 *             on error
 */
public FLVReader(FileChannel channel) throws IOException {
    if (null == channel) {
        log.warn("Reader was passed a null channel");
        log.debug("{}", org.apache.commons.lang3.builder.ToStringBuilder.reflectionToString(this));
    }
    if (!channel.isOpen()) {
        log.warn("Reader was passed a closed channel");
        return;
    }
    this.channel = channel;
    channelSize = channel.size();
    log.debug("Channel size: {}", channelSize);
    if (channel.position() > 0) {
        log.debug("Channel position: {}", channel.position());
        channel.position(0);
    }
    fillBuffer();
    postInitialize();
}
 

@Test
public void testMadviseDontNeedTrackedBuffers() throws IOException {
    try {
        MMapBuffer.setTrackingEnabled(false);
        MMapBuffer.madviseDontNeedTrackedBuffers();

        MMapBuffer.setTrackingEnabled(true);
        MMapBuffer.madviseDontNeedTrackedBuffers();

        final File tempFile = File.createTempFile("TestMMapBuffer", "");
        try (MMapBuffer ignored = new MMapBuffer(tempFile, 0, 10, FileChannel.MapMode.READ_WRITE, ByteOrder.nativeOrder())) {
            MMapBuffer.madviseDontNeedTrackedBuffers();
        }

        MMapBuffer.madviseDontNeedTrackedBuffers();
    } finally {
        MMapBuffer.setTrackingEnabled(false);
    }
}
 

public static Database open(FileFormat fileFormat, File file, boolean inMem,
                            Charset charset)
  throws Exception
{
  FileChannel channel = (inMem ? MemFileChannel.newChannel(
                             file, MemFileChannel.RW_CHANNEL_MODE)
                         : null);
  final Database db = new DatabaseBuilder(file).setReadOnly(true)
    .setAutoSync(getTestAutoSync()).setChannel(channel)
    .setCharset(charset).open();
  Assert.assertEquals("Wrong JetFormat.",
               DatabaseImpl.getFileFormatDetails(fileFormat).getFormat(),
               ((DatabaseImpl)db).getFormat());
  Assert.assertEquals("Wrong FileFormat.", fileFormat, db.getFileFormat());
  return db;
}
 

/**
 * lock odex
 *
 * @param bundleDexFile optimize dex file
 **/
public boolean LockExclusive(File bundleDexFile) {

    if (bundleDexFile == null) {
        return false;
    }
    try {
        File lockFile = new File(bundleDexFile.getParentFile().getAbsolutePath().concat("/lock"));
        if (!lockFile.exists()) {
            lockFile.createNewFile();
        }
        RandomAccessFile randomAccessFile = new RandomAccessFile(lockFile.getAbsolutePath(), "rw");
        FileChannel channel = randomAccessFile.getChannel();
        FileLock lock = channel.lock();
        if (!lock.isValid()) {
            return false;
        }
        RefCntInc(lockFile.getAbsolutePath(), lock, randomAccessFile, channel);
        return true;
    } catch (Exception e) {
        log.error(processName + " FileLock " + bundleDexFile.getParentFile().getAbsolutePath().concat("/lock") + " Lock FAIL! " + e.getMessage());
        return false;
    }
}
 

/**
 * Moved this code into it's own method so moveTo could use it when the move is across file systems
 */
private void copyAction(File srcFile, File destFile)
        throws FileNotFoundException, IOException {
    FileInputStream istream = new FileInputStream(srcFile);
    FileOutputStream ostream = new FileOutputStream(destFile);
    FileChannel input = istream.getChannel();
    FileChannel output = ostream.getChannel();

    try {
        input.transferTo(0, input.size(), output);
    } finally {
        istream.close();
        ostream.close();
        input.close();
        output.close();
    }
}
 

public static void copyFile(File src, File dest) throws IOException {
    if (!dest.exists()) {
        dest.createNewFile();
    }
    FileChannel source = null;
    FileChannel destination = null;
    try {
        source = new FileInputStream(src).getChannel();
        destination = new FileOutputStream(dest).getChannel();
        destination.transferFrom(source, 0, source.size());
    } finally {
        if (source != null) {
            source.close();
        }
        if (destination != null) {
            destination.close();
        }
    }
}
 

/**
 * Copies source file to target.
 *
 * @param source source file to copy.
 * @param target destination to copy to.
 * @return target as File.
 * @throws IOException when unable to copy.
 */
public static File copyFile(String source, String target) throws IOException {
    FileChannel inputChannel = null;
    FileChannel outputChannel = null;
    try {
        inputChannel = new FileInputStream(source).getChannel();
        outputChannel = new FileOutputStream(target).getChannel();
        outputChannel.transferFrom(inputChannel, 0, inputChannel.size());
    } finally {
        if (inputChannel != null) {
            inputChannel.close();
        }
        if (outputChannel != null) {
            outputChannel.close();
        }
    }
    return new File(target);
}
 

public int
read(
	byte		subsystem,
	FileChannel	chan )
 
	throws IOException
{
	if ( TRACE ){
		
		traceUsage( subsystem, OP_READ_FC);
	}
	
	try{
		return( chan.read(buffer ));
		
	}catch( IllegalArgumentException e ){
		
		dumpTrace(e);
		
		throw( e );
	}
}
 

private void acquireGlobalLock() {
	try {
		fc = FileChannel.open(Paths.get(System.getProperty("user.home"), XDMApp.GLOBAL_LOCK_FILE),
				EnumSet.of(StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING, StandardOpenOption.READ,
						StandardOpenOption.WRITE));
		int maxRetry = 10;
		for (int i = 0; i < maxRetry; i++) {
			fileLock = fc.tryLock();
			if (fileLock != null) {
				Logger.log("Lock acquired...");
				return;
			}

			// if lock is already acquired by some other process wait
			// and retry for at most 5 sec, after that throw error and
			// exit
			Thread.sleep(500);
		}
	} catch (Exception e) {
		e.printStackTrace();
	}

}
 

static public void copyFile(String source, String target) throws IOException {
    File sf = new File(source);
    if (!sf.exists()) {
        throw new IllegalArgumentException("source file does not exist.");
    }
    File tf = new File(target);
    tf.getParentFile().mkdirs();
    if (!tf.exists() && !tf.createNewFile()) {
        throw new RuntimeException("failed to create target file.");
    }

    FileChannel sc = null;
    FileChannel tc = null;
    try {
        tc = new FileOutputStream(tf).getChannel();
        sc = new FileInputStream(sf).getChannel();
        sc.transferTo(0, sc.size(), tc);
    } finally {
        if (null != sc) {
            sc.close();
        }
        if (null != tc) {
            tc.close();
        }
    }
}
 

public static FileChannel createMigrationTimestampFile(
    final File directory, final int fromVersion, final int toVersion)
{
    final String filename =
        MIGRATION_TIMESTAMP_FILE_PREFIX + fromVersion + "-to-" + toVersion + MIGRATION_TIMESTAMP_FILE_SUFFIX;
    final File timestampFile = new File(directory, filename);

    FileChannel fileChannel = null;

    try
    {
        fileChannel = FileChannel.open(timestampFile.toPath(), CREATE_NEW, READ, WRITE, SPARSE);
        fileChannel.force(true);
    }
    catch (final Exception ex)
    {
        System.err.println("Could not create migration timestamp file:" + timestampFile);
        LangUtil.rethrowUnchecked(ex);
    }

    return fileChannel;
}
 

private static void useFileChannel(File tmp) throws Throwable {
    tmp.delete();
    try (RandomAccessFile rf = new RandomAccessFile(tmp, "rw");
            FileChannel ch = rf.getChannel()) {
        final String bufContent = "0123456789";
        final int bufSize = bufContent.length();
        ByteBuffer writeBuf = ByteBuffer.allocateDirect(bufSize);
        writeBuf.put(bufContent.getBytes());

        writeBuf.flip();
        int writeSize = ch.write(writeBuf);
        assertEquals(writeSize, bufSize, "Wrong writeSize for FileChannel");

        ch.position(0);
        ByteBuffer readBuf = ByteBuffer.allocateDirect(bufSize);
        int readSize = ch.read(readBuf);
        assertEquals(readSize, bufSize, "Wrong readSize full for FileChannel");
        assertEquals(0, writeBuf.compareTo(readBuf), "Unexpected readBuf content");
    }
}
 

public static void main(String[] args) throws Throwable {
    try (FileChannel ch = FileChannel.open(BLK_PATH, READ);
         RandomAccessFile file = new RandomAccessFile(BLK_FNAME, "r")) {

        long size1 = ch.size();
        long size2 = file.length();
        if (size1 != size2) {
            throw new RuntimeException("size differs when retrieved" +
                    " in different ways: " + size1 + " != " + size2);
        }
        System.out.println("OK");

    } catch (NoSuchFileException nsfe) {
        System.err.println("File " + BLK_FNAME + " not found." +
                " Skipping test");
    } catch (AccessDeniedException ade) {
        System.err.println("Access to " + BLK_FNAME + " is denied." +
                " Run test as root.");
    }
}
 

private HaloDBFile(int fileId, File backingFile, DBDirectory dbDirectory, IndexFile indexFile, FileType fileType,
                   FileChannel channel, HaloDBOptions options) throws IOException {
    this.fileId = fileId;
    this.backingFile = backingFile;
    this.dbDirectory = dbDirectory;
    this.indexFile = indexFile;
    this.fileType = fileType;
    this.channel = channel;
    this.writeOffset = Ints.checkedCast(channel.size());
    this.options = options;
}
 

/**
 * Fill a region of a file with a given byte value.
 *
 * @param fileChannel to fill.
 * @param position    at which to start writing.
 * @param length      of the region to write.
 * @param value       to fill the region with.
 */
public static void fill(final FileChannel fileChannel, final long position, final long length, final byte value)
{
    try
    {
        final byte[] filler;
        if (0 != value)
        {
            filler = new byte[BLOCK_SIZE];
            Arrays.fill(filler, value);
        }
        else
        {
            filler = FILLER;
        }

        final ByteBuffer byteBuffer = ByteBuffer.wrap(filler);
        fileChannel.position(position);

        final int blocks = (int)(length / BLOCK_SIZE);
        final int blockRemainder = (int)(length % BLOCK_SIZE);

        for (int i = 0; i < blocks; i++)
        {
            byteBuffer.position(0);
            fileChannel.write(byteBuffer);
        }

        if (blockRemainder > 0)
        {
            byteBuffer.position(0);
            byteBuffer.limit(blockRemainder);
            fileChannel.write(byteBuffer);
        }
    }
    catch (final IOException ex)
    {
        LangUtil.rethrowUnchecked(ex);
    }
}
 

public static void main(String[] args) throws Exception {
    Path blah = Files.createTempFile("blah", null);
    blah.toFile().deleteOnExit();
    initTestFile(blah);

    for (int i=0; i<10; i++) {
        try (FileChannel fc = (generator.nextBoolean()) ?
                FileChannel.open(blah, READ) :
                new FileInputStream(blah.toFile()).getChannel()) {
            for (int j=0; j<100; j++) {
                long newPos = generator.nextInt(1000);
                fc.position(newPos);
                if (fc.position() != newPos)
                    throw new RuntimeException("Position failed");
            }
        }
    }

    for (int i=0; i<10; i++) {
        try (FileChannel fc = (generator.nextBoolean()) ?
                 FileChannel.open(blah, APPEND) :
                 new FileOutputStream(blah.toFile(), true).getChannel()) {
            for (int j=0; j<10; j++) {
                if (fc.position() != fc.size())
                    throw new RuntimeException("Position expected to be size");
                byte[] buf = new byte[generator.nextInt(100)];
                fc.write(ByteBuffer.wrap(buf));
            }
        }
    }

    Files.delete(blah);
}
 

/**
 * Create a new media server remuxer with auto-detection.
 * <p/>
 * The input stream is assumed TS.
 *
 * @param fileChannel  The starting FileChannel to be used for writing.
 * @param outputFormat The format of the remuxed stream.
 * @param isTV         Is the incoming stream from a TV Tuner?
 * @param mediaServer  The media server creating this instance.
 */
public MediaServerRemuxer(FileChannel fileChannel, int outputFormat, boolean isTV, MediaServer.Connection mediaServer)
{
  // Any initial size that is not a multiple of 188 is a waste since the extra bytes will not be used.
  this(fileChannel,
      27888 * TS_ALIGN /* 5MB; one quarter the max size */, outputFormat,
      isTV ? MPEGParser2.StreamFormat.ATSC : MPEGParser2.StreamFormat.FREE,
      MPEGParser2.SubFormat.UNKNOWN,
      MPEGParser2.TuneStringType.CHANNEL,
      0, 0, 0, 0, 0,
      mediaServer);
}
 

public static void main(String[] args) throws Throwable {
    Path path = Files.createTempFile("LoopingTruncate.tmp", null);
    try (FileChannel fc = FileChannel.open(path, CREATE, WRITE)) {
        fc.position(FATEFUL_SIZE + 1L);
        fc.write(ByteBuffer.wrap(new byte[] {0}));

        Thread th = new Thread(() -> {
            try {
                fc.truncate(FATEFUL_SIZE);
            } catch (ClosedByInterruptException ignore) {
            } catch (Exception e) {
                throw new RuntimeException(e);
            }});
        th.start();
        th.join(TIMEOUT);

        if (th.isAlive()) {
            System.err.println("=== Stack trace of the guilty thread:");
            for (StackTraceElement el : th.getStackTrace()) {
                System.err.println("\t" + el);
            }
            System.err.println("===");

            th.interrupt();
            th.join();
            throw new RuntimeException("Failed to complete on time");
        }
    } finally {
        Files.deleteIfExists(path);
    }
}
 

/**
 * Creates new FileChannelMemoryMappedBoundedData, creating a memory mapped file at the given path.
 * Each mapped region (= ByteBuffer) will be of the given size.
 */
public static FileChannelMemoryMappedBoundedData createWithRegionSize(Path memMappedFilePath, int regionSize) throws IOException {
	checkNotNull(memMappedFilePath, "memMappedFilePath");
	checkArgument(regionSize > 0, "regions size most be > 0");

	final FileChannel fileChannel = FileChannel.open(memMappedFilePath,
			StandardOpenOption.READ, StandardOpenOption.WRITE, StandardOpenOption.CREATE_NEW);

	return new FileChannelMemoryMappedBoundedData(memMappedFilePath, fileChannel, regionSize);
}
 

private void expandIfNecessary(int dataLength) throws IOException {
    int elementLength = dataLength + 4;
    int remainingBytes = remainingBytes();
    if (remainingBytes < elementLength) {
        int newLength;
        int previousLength = this.fileLength;
        do {
            remainingBytes += previousLength;
            newLength = previousLength << 1;
            previousLength = newLength;
        } while (remainingBytes < elementLength);
        setLength(newLength);
        int endOfLastElement = wrapPosition((this.last.position + 4) + this.last.length);
        if (endOfLastElement < this.first.position) {
            FileChannel channel = this.raf.getChannel();
            channel.position((long) this.fileLength);
            int count = endOfLastElement - 4;
            if (channel.transferTo(16, (long) count, channel) != ((long) count)) {
                throw new AssertionError("Copied insufficient number of bytes!");
            }
        }
        if (this.last.position < this.first.position) {
            int newLastPosition = (this.fileLength + this.last.position) - 16;
            writeHeader(newLength, this.elementCount, this.first.position, newLastPosition);
            this.last = new Element(newLastPosition, this.last.length);
        } else {
            writeHeader(newLength, this.elementCount, this.first.position, this.last.position);
        }
        this.fileLength = newLength;
    }
}
 

private void releaseLock(FileLock lock) throws IOException {
  if (lock != null && lock.isValid()) {
    FileChannel lockChannel = lock.channel();
    lock.release();
    lockChannel.close();
  }
}
 

private boolean inReady() {
    try {
    return (((in != null) && (in.available() > 0))
            || (ch instanceof FileChannel)); // ## RBC.available()?
    } catch (IOException x) {
    return false;
    }
}
 

public ByteBuffer getBuffer(DumpIndex idx) throws IOException {
    if (cache.containsKey(idx)) {
        MappedByteBuffer b = cache.get(idx);
        b.position(0);
        return b.duplicate().order(b.order());
    }
    FileChannel channel = dump.getChannel();
    MappedByteBuffer res = channel.map(FileChannel.MapMode.READ_ONLY, idx.filePos, idx.size);
    res.order(ByteOrder.LITTLE_ENDIAN);
    cache.put(idx, res);
    return res.duplicate().order(res.order());
}