检查目录是否存在。

 档案档案=新档案（c：\\cygwin\ \cygwin.bat）; 
 if（！file.isDirectory（））
 file = file.getParentFile（）; 
 if（file.exists（））{
 ... 
} 
 

$ b $看起来像file.canWrite（）没有给你一个明确的指示，如果你有权限写入目录。

I need to determine if a user-supplied String is a valid file path (i.e. if createNewFile() will succeed or throw an Exception) but i don't want to bloat the file system with useless files created just for validation purposes, so is there a way to determine if the String i have is a valid file path without attempting to create the file?

I know the definition of "valid file path" varies depending on the OS, but i was wondering if there was any quick way of accepting "C:/foo" or "/foo" and rejecting "banana"...a possible approach may be attempting to create the file and eventually deleting it if the creation succeeded, but i hope there is a more elegant way of achieving the same result...

This would check for the existance of the directory as well.

File file = new File("c:\\cygwin\\cygwin.bat");
if (!file.isDirectory())
   file = file.getParentFile();
if (file.exists()){
    ...
}

It seems like file.canWrite() does not give you a clear indication if you have permissions to write to the directory.