文件重命名为android，JAVA后文件未找到异常

Question

我试图在将文件上传到服务器之前重命名该文件....文件正在重命名，但它正在抛出fileNotFoundException。请帮忙

        HttpURLConnection conn;
        DataOutputStream dos;
        String lineEnd = "\r\n";
        String twoHyphens = "--";
        String boundary = "*****";
        int bytesRead, bytesAvailable, bufferSize;
        byte[] buffer;
        int maxBufferSize = 1024 * 1024;
        int maxSize = 1024 * 1024;
        File sourceFile = new File(fileuri);
        final String name = fileuri.substring(fileuri.lastIndexOf("/") + 1);
        String directory = fileuri.replace(name, "");
        File to = new File(directory, filename);
        sourceFile.renameTo(to);
        String path=sourceFile.getPath().toString();
        final long length = sourceFile.length();
        if (length / maxSize > 1) {

            runOnUiThread(new Runnable() {
                public void run() {
                    Toast.makeText(getApplicationContext(), "File Larger than 1MB", Toast.LENGTH_SHORT).show();
                }
            });
            return 0;
        }

        if (!sourceFile.isFile()) {


            Log.e("uploadFile", "Source File not exist :" + imagepath);

            runOnUiThread(new Runnable() {
                public void run() {
                    Toast.makeText(getApplicationContext(), "Source File not exist :", Toast.LENGTH_SHORT).show();
                }
            });

            return 0;`