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

Example 6 with FileLock

use of java.nio.channels.FileLock in project android_frameworks_base by ParanoidAndroid.

the class MiniThumbFile method saveMiniThumbToFile.

public synchronized void saveMiniThumbToFile(byte[] data, long id, long magic) throws IOException {
    RandomAccessFile r = miniThumbDataFile();
    if (r == null)
        return;
    long pos = id * BYTES_PER_MINTHUMB;
    FileLock lock = null;
    try {
        if (data != null) {
            if (data.length > BYTES_PER_MINTHUMB - HEADER_SIZE) {
                // not enough space to store it.
                return;
            }
            mBuffer.clear();
            mBuffer.put((byte) 1);
            mBuffer.putLong(magic);
            mBuffer.putInt(data.length);
            mBuffer.put(data);
            mBuffer.flip();
            lock = mChannel.lock(pos, BYTES_PER_MINTHUMB, false);
            mChannel.write(mBuffer, pos);
        }
    } catch (IOException ex) {
        Log.e(TAG, "couldn't save mini thumbnail data for " + id + "; ", ex);
        throw ex;
    } catch (RuntimeException ex) {
        // Other NIO related exception like disk full, read only channel..etc
        Log.e(TAG, "couldn't save mini thumbnail data for " + id + "; disk full or mount read-only? " + ex.getClass());
    } finally {
        try {
            if (lock != null)
                lock.release();
        } catch (IOException ex) {
        // ignore it.
        }
    }
}

Example 7 with FileLock

use of java.nio.channels.FileLock in project atlas by alibaba.

the class AtlasFileLock method LockExclusive.

/*
     * Hold a exclusive lock, file is the directory
     */
public boolean LockExclusive(File orgFile) {
    RandomAccessFile fOs = null;
    FileChannel fChannel = null;
    try {
        if (orgFile == null) {
            return false;
        }
        File file;
        if (orgFile.exists() && orgFile.isDirectory()) {
            file = new File(orgFile.getAbsolutePath().concat("/lock"));
        } else {
            file = new File(orgFile.getParentFile().getAbsolutePath().concat("/lock"));
        }
        if (file.exists() != true) {
            file.createNewFile();
        }
        fOs = new RandomAccessFile(file.getAbsolutePath(), "rw");
        fChannel = fOs.getChannel();
        FileLock fFileLock = fChannel.lock();
        if (fFileLock.isValid()) {
            RefCntInc(file.getAbsolutePath(), fFileLock, fOs, fChannel);
            return true;
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    return false;
}

Example 8 with FileLock

use of java.nio.channels.FileLock in project dubbo by alibaba.

the class AbstractRegistry method doSaveProperties.

public void doSaveProperties(long version) {
    if (version < lastCacheChanged.get()) {
        return;
    }
    if (file == null) {
        return;
    }
    Properties newProperties = new Properties();
    // 保存之前先读取一遍，防止多个注册中心之间冲突
    InputStream in = null;
    try {
        if (file.exists()) {
            in = new FileInputStream(file);
            newProperties.load(in);
        }
    } catch (Throwable e) {
        logger.warn("Failed to load registry store file, cause: " + e.getMessage(), e);
    } finally {
        if (in != null) {
            try {
                in.close();
            } catch (IOException e) {
                logger.warn(e.getMessage(), e);
            }
        }
    }
    // 保存
    try {
        newProperties.putAll(properties);
        File lockfile = new File(file.getAbsolutePath() + ".lock");
        if (!lockfile.exists()) {
            lockfile.createNewFile();
        }
        RandomAccessFile raf = new RandomAccessFile(lockfile, "rw");
        try {
            FileChannel channel = raf.getChannel();
            try {
                FileLock lock = channel.tryLock();
                if (lock == null) {
                    throw new IOException("Can not lock the registry cache file " + file.getAbsolutePath() + ", ignore and retry later, maybe multi java process use the file, please config: dubbo.registry.file=xxx.properties");
                }
                // 保存
                try {
                    if (!file.exists()) {
                        file.createNewFile();
                    }
                    FileOutputStream outputFile = new FileOutputStream(file);
                    try {
                        newProperties.store(outputFile, "Dubbo Registry Cache");
                    } finally {
                        outputFile.close();
                    }
                } finally {
                    lock.release();
                }
            } finally {
                channel.close();
            }
        } finally {
            raf.close();
        }
    } catch (Throwable e) {
        if (version < lastCacheChanged.get()) {
            return;
        } else {
            registryCacheExecutor.execute(new SaveProperties(lastCacheChanged.incrementAndGet()));
        }
        logger.warn("Failed to save registry store file, cause: " + e.getMessage(), e);
    }
}

Example 9 with FileLock

use of java.nio.channels.FileLock in project disconf by knightliao.

the class OsUtil method transferFileAtom.

/**
     * @param src
     * @param dest
     *
     * @return void
     *
     * @Description: 具有重试机制的 ATOM 转移文件 ，并且会校验文件是否一致 才替换
     * @author liaoqiqi
     * @date 2013-6-20
     */
public static void transferFileAtom(File src, File dest, boolean isDeleteSource) throws Exception {
    // 文件锁所在文件
    File lockFile = new File(dest + ".lock");
    FileOutputStream outStream = null;
    FileLock lock = null;
    try {
        int tryTime = 0;
        while (tryTime < 3) {
            try {
                outStream = new FileOutputStream(lockFile);
                FileChannel channel = outStream.getChannel();
                lock = channel.tryLock();
                if (lock != null) {
                    if (dest.exists()) {
                        // 判断内容是否一样
                        if (FileUtils.isFileEqual(src, dest)) {
                            // 内容如果一样，就只需要删除源文件就行了
                            if (isDeleteSource) {
                                src.delete();
                            }
                            break;
                        }
                    }
                    logger.debug("start to replace " + src.getAbsolutePath() + " to " + dest.getAbsolutePath());
                    // 转移
                    transferFile(src, dest);
                    // 删除源文件
                    if (isDeleteSource) {
                        src.delete();
                    }
                    break;
                }
            } catch (FileNotFoundException e) {
                // 打不开文件，则后面进行重试
                logger.warn(e.toString());
            } finally {
                // 释放锁，通道；删除锁文件
                if (null != lock) {
                    try {
                        lock.release();
                    } catch (IOException e) {
                        logger.warn(e.toString());
                    }
                    if (lockFile != null) {
                        lockFile.delete();
                    }
                }
                if (outStream != null) {
                    try {
                        outStream.close();
                    } catch (IOException e) {
                        logger.warn(e.toString());
                    }
                }
            }
            // 进行重试
            logger.warn("try lock failed. sleep and try " + tryTime);
            tryTime++;
            try {
                Thread.sleep(1000 * tryTime);
            } catch (Exception e) {
                System.out.print("");
            }
        }
    } catch (IOException e) {
        logger.warn(e.toString());
    }
}

Example 10 with FileLock

use of java.nio.channels.FileLock in project neo4j by neo4j.

the class SingleFilePageSwapperTest method creatingSwapperForInternallyLockedFileMustThrow.

@Test
public void creatingSwapperForInternallyLockedFileMustThrow() throws Exception {
    // no file locking on Windows.
    assumeFalse("No file locking on Windows", SystemUtils.IS_OS_WINDOWS);
    PageSwapperFactory factory = createSwapperFactory();
    factory.setFileSystemAbstraction(fileSystem);
    File file = testDir.file("file");
    StoreFileChannel channel = fileSystem.create(file);
    try (FileLock fileLock = channel.tryLock()) {
        assertThat(fileLock, is(not(nullValue())));
        expectedException.expect(FileLockException.class);
        createSwapper(factory, file, 4, NO_CALLBACK, true);
    }
}