java 下面执行外部程序

public void execBat(){String path = String.format("%srunMain.bat", getAppRootDir());try {System.out.println(String.format("bat path = %s", path));System.out.println(System.currentTimeMillis());Process process = Runtime.getRuntime().exec(path);BufferedReader read = new BufferedReader(new InputStreamReader(                      process.getInputStream()));         String str = null;         while ((str = read.readLine()) != null) {            System.out.println(str);         }System.out.println(System.currentTimeMillis());} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}

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