Android 获取root权限 兑现重启

怎么获取root权限，这是个问题。网上说用mk+uid能获得，早之前我只会用cmd去获取，而且还要安装一个superuser前提还要是已经破解过的代码如下：(求大神赐教mk的方法) Process process = null;                        DataOutputStream os = null;                        try {                            process = Runtime.getRuntime().exec("su");                            os = new DataOutputStream(process.getOutputStream());                            os.writeBytes(" exit \n");                            os.writeBytes(" exit \n");                            os.flush();                            process.waitFor();                        } catch (Exception e) {                        } finally {                            try {                                if (os != null) {                                    os.close();                                }                                process.destroy();                            } catch (Exception e) {                            }                        }//先获取应用root Process process = null;    DataOutputStream os = null;    try {     process = Runtime.getRuntime().exec("su");     os = new DataOutputStream(process.getOutputStream());     os.writeBytes(" reboot -p \n");//重启代码= = 我在cmd里面su了之后还是不能关机，只能重启。哎。     os.flush();     process.waitFor();    } catch (Exception e) {    } finally {     try {      if (os != null) {       os.close();      }      process.destroy();     } catch (Exception e) {     }    }求大神赐教真正获取root权限。 

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