Java FileChannel.close方法代码示例

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
private static String extractDatabase(Context context) {
    try {
        File external = context.getExternalFilesDir(null);
        File data = Environment.getDataDirectory();
        if (external != null && external.canWrite()) {
            String dataDBPath = "data/" + context.getPackageName() + "/databases/chuck.db";
            String extractDBPath = "chuckdb.temp";
            File dataDB = new File(data, dataDBPath);
            File extractDB = new File(external, extractDBPath);
            if (dataDB.exists()) {
                FileChannel in = new FileInputStream(dataDB).getChannel();
                FileChannel out = new FileOutputStream(extractDB).getChannel();
                out.transferFrom(in, 0, in.size());
                in.close();
                out.close();
                return extractDB.getAbsolutePath();
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    return null;
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
/**
 * Randomly overwrite some bytes in the translog files
 */
private void corruptTranslogs(Path directory) throws Exception {
    Path[] files = FileSystemUtils.files(directory, "translog-*");
    for (Path file : files) {
        logger.info("--> corrupting {}...", file);
        FileChannel f = FileChannel.open(file, StandardOpenOption.READ, StandardOpenOption.WRITE);
        int corruptions = scaledRandomIntBetween(10, 50);
        for (int i = 0; i < corruptions; i++) {
            // note: with the current logic, this will sometimes be a no-op
            long pos = randomIntBetween(0, (int) f.size());
            ByteBuffer junk = ByteBuffer.wrap(new byte[]{randomByte()});
            f.write(junk, pos);
        }
        f.close();
    }
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
private static void analyzeAndTagFile(String inputFilename) throws Exception {
	File file = new File(inputFilename);
	String outFilename = config.getString("output.dirpath") + file.getName() + config.getString("output.postfix");
	RandomAccessFile outStream = new RandomAccessFile(outFilename, "rw");
	FileChannel outChannel = outStream.getChannel();
	LineIterator it = FileUtils.lineIterator(file, config.getString("input.charset"));


	try {
		while (it.hasNext()) {
			String line = it.nextLine().trim();

			if (!"".equals(line)) {
				outChannel.write(Charset.forName(config.getString("output.charset")).newEncoder().encode(CharBuffer.wrap(tagger.tag(komoran.analyze(line)) + config.getString("delimiter.line"))));
			}
		}
	}
	finally {
		LineIterator.closeQuietly(it);
		outStream.close();
		outChannel.close();
	}
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
public static void copyFile(File src, File dest) throws IOException {
    FileChannel inChannel = null;
    FileChannel outChannel = null;

    try {
        if (!dest.exists()) {
            dest.createNewFile();
        }

        inChannel = (new FileInputStream(src)).getChannel();
        outChannel = (new FileOutputStream(dest)).getChannel();
        inChannel.transferTo(0L, inChannel.size(), outChannel);
    } finally {
        if (inChannel != null) {
            inChannel.close();
        }

        if (outChannel != null) {
            outChannel.close();
        }

    }

}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
/**
 * 将整个文件读取为字节数组
 *
 * @param path
 * @return
 */
public static byte[] readBytes(String path) {
    try {
        FileInputStream fis = new FileInputStream(path);
        FileChannel channel = fis.getChannel();
        int fileSize = (int) channel.size();
        ByteBuffer byteBuffer = ByteBuffer.allocate(fileSize);
        channel.read(byteBuffer);
        byteBuffer.flip();
        byte[] bytes = byteBuffer.array();
        byteBuffer.clear();
        channel.close();
        fis.close();
        return bytes;
    } catch (Exception e) {
        logger.warn("读取" + path + "时发生异常" + e);
        logger.warn("开始生成" + path + " ...");
    }

    return null;
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
/**
 * 复制文件
 * 
 * @param source
 * @param target
 * @throws IOException
 */
public void copy(File source, File target) throws IOException
{
	// FileInputStream sourceStream = null;
	// FileInputStream targetStream = null;
	
	FileChannel inChannel = new FileInputStream(source).getChannel();
	FileChannel outChannel = new FileOutputStream(target).getChannel();
	try
	{
		inChannel.transferTo(0, inChannel.size(), outChannel);
	}
	catch (IOException e)
	{
		Log.E(TAG, "Failed to copy file. " + e.toString());
		e.printStackTrace();
	}
	finally
	{
		if (inChannel != null)
		{
			inChannel.close();
		}
		if (outChannel != null)
		{
			outChannel.close();
		}
		
		// if (targetStream != null)
		// {
		// targetStream.close();
		// }
		// if (sourceStream != null)
		// {
		// sourceStream.close();
		// }
	}
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
/**
 * Tests random access reading
 * <p>
 * Only executes if the reader implements {@link RandomAccessContent}.
 */
@Test
public void testRandomAccessRead() throws Exception
{
    ContentStore store = getStore();
    String contentUrl = getExistingContentUrl();
    if (contentUrl == null)
    {
        logger.warn("Store test testRandomAccessRead not possible on " + store.getClass().getName());
        return;
    }
    // Get the reader
    ContentReader reader = store.getReader(contentUrl);
    assertNotNull("Reader should never be null", reader);

    FileChannel fileChannel = reader.getFileChannel();
    assertNotNull("No channel given", fileChannel);
    
    // check that no other content access is allowed
    try
    {
        reader.getReadableChannel();
        fail("Second channel access allowed");
    }
    catch (RuntimeException e)
    {
        // expected
    }
    fileChannel.close();
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
@Test
public void shouldThrowLockExceptionIfFailedToLockStateDirectory() throws Exception {
    final File taskDirectory = stateDirectory.directoryForTask(taskId);
    final FileChannel channel = FileChannel.open(new File(taskDirectory,
                                                          StateDirectory.LOCK_FILE_NAME).toPath(),
                                                 StandardOpenOption.CREATE,
                                                 StandardOpenOption.WRITE);
    // lock the task directory
    final FileLock lock = channel.lock();

    try {
        new ProcessorStateManager(
            taskId,
            noPartitions,
            false,
            stateDirectory,
            Collections.<String, String>emptyMap(),
            changelogReader,
            false);
        fail("Should have thrown LockException");
    } catch (final LockException e) {
       // pass
    } finally {
        lock.release();
        channel.close();
    }
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
public static void copyFile(File from, File to) throws IOException {
    if (!from.exists()) {
        throw new FileNotFoundException();
    }
    if (from.isDirectory() || to.isDirectory()) {
        throw new FileNotFoundException();
    }
    FileInputStream fi = null;
    FileChannel in = null;
    FileOutputStream fo = null;
    FileChannel out = null;
    try {
        if (!to.exists()) {
            to.createNewFile();
        }
        fi = new FileInputStream(from);
        in = fi.getChannel();
        fo = new FileOutputStream(to);
        out = fo.getChannel();
        in.transferTo(0, in.size(), out);
    } finally {
        if (fi != null) fi.close();
        if (in != null) in.close();
        if (fo != null) fo.close();
        if (out != null) out.close();
    }
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
/**
 * Writes data to a file.
 *
 * @param data
 * @throws IOException
 */
protected void writeToFile(List<ExportEntry> data) throws IOException {
    FileChannel fc = fileOutpuStream.getChannel();
    byte[] lineFeed = "\n".getBytes(Charset.forName("UTF-8"));

    for (ExportEntry entry : data) {
        byte[] messageBytes = entry.toByteEntryLine();
        fc.write(ByteBuffer.wrap(messageBytes));
        fc.write(ByteBuffer.wrap(lineFeed));
    }

    fc.close();
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
/**
 * {@inheritDoc}
 */
@Override
protected void writeToFile(final List<ExportEntry> data) throws IOException {
    FileChannel channel = fileOutputStream.getChannel();
    byte[] lineFeed = "\n".getBytes(Charset.forName("UTF-8"));

    for (ExportEntry entry : data) {
        byte[] messageBytes = entry.toByteEntryLine();
        channel.write(ByteBuffer.wrap(messageBytes));
        channel.write(ByteBuffer.wrap(lineFeed));
    }

    channel.close();
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
public void addLibrary(String name) throws Exception {
    OpenArch.log.info(String.format("Loading %s.", name));

    String libPath = String.format("/assets/%s/lib/%s", OpenArch.MODID, name);
    URL libUrl = getClass().getResource(libPath);
    ReadableByteChannel in = Channels.newChannel(libUrl.openStream());

    String tmpLibPath = String.format("%s/%s", tmpDir, name);
    File tmpLibFile = new File(tmpLibPath);

    if (tmpLibFile.exists()) {
        return;
    }

    FileChannel out = new FileOutputStream(tmpLibFile).getChannel();

    out.transferFrom(in, 0, Long.MAX_VALUE);

    tmpLibFile.deleteOnExit();

    if (!tmpLibFile.setReadable(true, false)) {
        throw new Exception("Failed to set readable flag on the library");
    }

    if (!tmpLibFile.setWritable(true, false)) {
        throw new Exception("Failed to set writable flag on the library");
    }

    if (!tmpLibFile.setExecutable(true, false)) {
        throw new Exception("Failed to set executable flag on the library");
    }

    out.close();
    in.close();
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
boolean lockGlobalState(final int retry) throws IOException {
    if (globalStateLock != null) {
        log.trace("{} Found cached state dir lock for the global task", logPrefix);
        return true;
    }

    final File lockFile = new File(globalStateDir(), LOCK_FILE_NAME);
    final FileChannel channel;
    try {
        channel = FileChannel.open(lockFile.toPath(), StandardOpenOption.CREATE, StandardOpenOption.WRITE);
    } catch (NoSuchFileException e) {
        // FileChannel.open(..) could throw NoSuchFileException when there is another thread
        // concurrently deleting the parent directory (i.e. the directory of the taskId) of the lock
        // file, in this case we will return immediately indicating locking failed.
        return false;
    }
    final FileLock fileLock = tryLock(retry, channel);
    if (fileLock == null) {
        channel.close();
        return false;
    }
    globalStateChannel = channel;
    globalStateLock = fileLock;

    log.debug("{} Acquired global state dir lock", logPrefix);

    return true;
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
private TrieDictionary(File data) throws IOException {
    this.array = null;

    FileInputStream ins = new FileInputStream(data);
    FileChannel channel = ins.getChannel();
    
    try {
        this.buffer = channel.map(MapMode.READ_ONLY, 0, channel.size());
    } finally {
        channel.close();
        ins.close();
    }
}
 

import java.nio.channels.FileChannel; //导入方法依赖的package包/类
/**
 * unlock odex file
 **/
public void unLock(File targetFile) {

    File lockFile = new File(targetFile.getParentFile().getAbsolutePath().concat("/lock"));
    if (!lockFile.exists()) {
        return;
    }
    if (this.mRefCountMap.containsKey(lockFile.getAbsolutePath())) {
        FileLockCount fileLockCount = this.mRefCountMap.get(lockFile.getAbsolutePath());
        if (fileLockCount != null) {
            java.nio.channels.FileLock fileLock = fileLockCount.mFileLock;
            RandomAccessFile randomAccessFile = fileLockCount.fOs;
            FileChannel fileChannel = fileLockCount.fChannel;
            try {
                if (RefCntDec(lockFile.getAbsolutePath()) <= 0) {
                    if (fileLock != null && fileLock.isValid()) {
                        fileLock.release();
                    }
                    if (randomAccessFile != null) {
                        randomAccessFile.close();
                    }
                    if (fileChannel != null) {
                        fileChannel.close();
                    }
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}