如何使用进程构建器将文件从/ mnt / sdcard复制到应用程序目录

Question

我想使用流程构建器将 / mnt / sdcard 中的文件复制到应用程序目录

public void onClick(View arg0) {

ProcessBuilder builder = new ProcessBuilder(new String[] { "su", "cat   /mnt/sdcard/debug_settings.txt > /data/data/com.sample.project/filetest.txt" });

Process process;
    try {
        process = builder.start();
         /*InputStream is = process.getInputStream();
            InputStreamReader isr = new InputStreamReader(is);
            BufferedReader br = new BufferedReader(isr);
            String line;
            while ((line = br.readLine()) != null) {
              System.out.println(line);
            }*/
         int suProcessRetval = process.waitFor();
            Log.d("Sahil", "suProcessRetval ="+suProcessRetval);
            System.out.println("Program terminated!");

    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
         Log.e("Sahil", "Could not run process", e);
    } catch (InterruptedException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
       }

 }

我不确定如何继续下去。

如果我跑

"cat/mnt/sdcard/debug_settings.txt > /data/data/com.sample.project/filetest.txt" 

来自shell，它已经复制了内容。