JAVA File Lock

ゝ一纸荒年。 2022-08-12 08:59 54阅读 0赞

package fileLock;
    
    import java.io.File;
    import java.io.RandomAccessFile;
    import java.util.Collection;
    import java.util.Iterator;
    import java.util.concurrent.Callable;
    import java.util.concurrent.ExecutorService;
    import java.util.concurrent.Executors;
    
    import org.apache.commons.io.FileUtils;
    import org.apache.commons.io.IOUtils;
    
    /**
     * @ClassName: FileLock
     * @Description: TODO
     * @author Zhou Shengshuai
     * @date 2014年9月22日 下午2:03:04
     * 
     */
    public class FileLock {
    	private ExecutorService threadPool = null;
    	private Collection<File> files = null;
    
    	public void initial() {
    		threadPool = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
    
    		files = FileUtils.listFiles(new File("lock"), new String[] { "lck", "LCK" }, false);
    	}
    
    	public void execute() {
    		Iterator<File> iterator = files.iterator();
    		while (iterator.hasNext()) {
    			File file = iterator.next();
    
    			ThreadTask threadTask = new ThreadTask(file);
    			threadPool.submit(threadTask);
    		}
    	}
    
    	public void destroy() {
    		threadPool.shutdown();
    
    		while (!threadPool.isTerminated())
    			;
    	}
    
    	public static void main(String[] args) {
    		FileLock fileLock = new FileLock();
    
    		fileLock.initial();
    		fileLock.execute();
    		fileLock.destroy();
    	}
    }
    
    class ThreadTask implements Callable<File> {
    	private File file = null;
    
    	public ThreadTask(File file) {
    		this.file = file;
    	}
    
    	@Override
    	public File call() throws Exception {
    		if (file == null || !file.isFile()) {
    			throw new Exception("File is null or non-file");
    		}
    
    		RandomAccessFile randomAccessFile = new RandomAccessFile(file, "rws");
    		java.nio.channels.FileLock fileLock = null;
    
    		while (true) {
    			fileLock = randomAccessFile.getChannel().tryLock();
    
    			if (fileLock != null) {
    				break;
    			}
    		}
    
    		randomAccessFile.writeBytes("123\n");
    
    		if (fileLock != null) {
    			fileLock.release();
    		}
    
    		IOUtils.closeQuietly(randomAccessFile);
    
    		return file;
    	}
    
    }