我目前正在通过tcp连接将文件从服务器传输到客户端。该文件存在于服务器的sharedroot目录中的某个位置。这是我的上传服务器上传到客户端方法的示例代码。

public void upload(String filename, DataOutputStream out) throws IOException {
        File fname = null;
        if (filename.contains(sharedroot)) {   //this is if the client provides a proper filepath with the filename
            fname = new File(filename);
        }else {      //if client only provides a filename without path
            fname = new File(filename);  
//"..\\..\\"+   //i was working around with this, but somehow just making the file whether or not it contains the sharedroot seems to give me the "best" output so far...
        }

        System.out.println(fname.getCanonicalPath());

        if (fname.isDirectory()) {
            System.out.println("File is a directory");
            String quit = "404 not found";
            sendOut(quit, out);
            return;
        }

        String path = fname.getAbsolutePath();
        System.out.println(path);

        if (fname.isFile()) {
            String canonpath = fname.getCanonicalPath();
            if (canonpath.contains(sharedroot)) {
                try {
                    FileInputStream in = new FileInputStream(fname);

                    byte[] buffer = new byte[1024];

                    out.writeInt(fname.getName().length());
                    out.write(fname.getName().getBytes(), 0, fname.getName().length()); // writes file name only, not
                                                                                        // including the path

                    long size = fname.length();
                    out.writeLong(size);

                    while (size > 0) {
                        int len = in.read(buffer, 0, buffer.length);
                        out.write(buffer, 0, len);
                        size -= len;
                    }
                } catch (Exception e) {
                    System.out.println("Error occurred in uploading file to client. Please try again");
                }
            }else {
                System.out.println("File not in shared directory");
                String quit = "404 not found";
                sendOut(quit, out);
            }
        }else {
            System.out.println("File not exists");
            String quit = "404 not found";
            sendOut(quit, out);
        }
    }

下面所示的getcanonicalpath（）和getabsolutepath（）给出的输出是错误的，因为它检查的是我的eclipse目录，而不是sharedroot目录。如何获取文件的文件路径，以便将其与sharedoot进行比较，并确保它存在于sharedoot中？sharedroot将是例如：d:\seant\2unifiles\1。2005年3年级
d:\seant\eclipse workspace\dcn3005\Teach1练习.pdf
d:\seant\eclipse workspace\dcn3005\Teach1练习.pdf
文件不存在