java - 将文件粘贴到文件夹中时获取文件夹的路径

Question

在某个文件夹中选择粘贴选项(复制文件时)时如何生成事件，其中该事件应获取选择粘贴选项的文件夹的路径。

Answer 1

此代码监视目录中添加、删除或修改的文件:

Path testDirectory = Files.createTempDirectory( getClass().getName());
WatchService watcher = FileSystems.getDefault().newWatchService();
testDirectory.register( watcher,
    StandardWatchEventKinds.ENTRY_CREATE, 
    StandardWatchEventKinds.ENTRY_MODIFY, 
    StandardWatchEventKinds.ENTRY_DELETE );
for(;;) {
   WatchKey key = watcher.take();
   log( "key = watcher.take()" );
   if( key.isValid()) {
      log( "key.isValid()" );
      List< WatchEvent< ? >> lst = key.pollEvents();
      for( WatchEvent<?> e : lst ) {
         log( "WatchEvent polled: " + e.kind() + ": " + e.context());
         if( e.kind() == StandardWatchEventKinds.ENTRY_CREATE ) {
            Path path = (Path)e.context();
            File file = path.toFile();
            addFile( new File( testDirectory.toFile(), file.getPath()));
         }
         else if( e.kind() == StandardWatchEventKinds.ENTRY_DELETE ) {
            Path path = (Path)e.context();
            File file = path.toFile();
            removeFile( new File( testDirectory.toFile(), file.getPath()));
         }
      }
      key.reset();
   }
}

这段代码涉及到的类有:

• Path
• WatchService
• StandardWatchEventKinds

This part of the io tutorial显示更多内容并解释此 API 的动机。