Java WatchService监视文件变动

系统管理员 2022-07-13 13:52 156阅读 0赞

package testfile;
    
    import java.io.BufferedReader;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileOutputStream;
    import java.io.FileReader;
    import java.io.FileWriter;
    import java.io.FilenameFilter;
    import java.io.IOException;
    import java.io.InputStreamReader;
    import java.io.ObjectInputStream;
    import java.io.ObjectOutputStream;
    import java.io.PrintStream;
    import java.io.PushbackReader;
    import java.io.RandomAccessFile;
    import java.nio.ByteBuffer;
    import java.nio.CharBuffer;
    import java.nio.MappedByteBuffer;
    import java.nio.channels.FileChannel;
    import java.nio.channels.FileChannel.MapMode;
    import java.nio.charset.Charset;
    import java.nio.charset.CharsetDecoder;
    import java.nio.charset.CharsetEncoder;
    import java.nio.file.FileStore;
    import java.nio.file.FileSystem;
    import java.nio.file.FileSystems;
    import java.nio.file.Files;
    import java.nio.file.Path;
    import java.nio.file.Paths;
    import java.nio.file.StandardWatchEventKinds;
    import java.nio.file.WatchEvent;
    import java.nio.file.WatchKey;
    import java.nio.file.WatchService;
    import java.util.SortedMap;
    
    public class TestFile {
    
        /** * @param args */
        public static void main(String[] args) throws IOException{
    
            WatchService ws = FileSystems.getDefault().newWatchService();
            Paths.get("c:").register(ws, StandardWatchEventKinds.ENTRY_CREATE,
                    StandardWatchEventKinds.ENTRY_DELETE,
                    StandardWatchEventKinds.ENTRY_MODIFY);
            while (true) {
                WatchKey key;
                try {
                    key = ws.take();
                    for (WatchEvent<?> event : key.pollEvents()) {
                        System.out.println(event.context() + "文件发生了" + event.kind());
                    }
                    boolean valid = key.reset();
                    if (!valid) {
                        break;
                    }
                } catch (InterruptedException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
    
            }
        }
    
    
    }

来自《java疯狂讲义》