public class ExecCommond{

public ExecCommond(){}

/**

  * 执行一条命令

  * @param execStr String 命令字符串

  * @return String 执行命令错误时的信息。

  */

 public static String  exec(String execStr) {

    Runtime runtime = Runtime.getRuntime(); 取得当前运行期对象

    String   outInfo=""; //执行错误的输出信息

    try {

          String[] args = new String[] {"sh", "-c", execStr};//执行linux下的命令

              //执行windows下的命令

//                   String[] args = new String[] {"cmd", "-c", execStr};

      Process proc = runtime.exec(args); //启动另一个进程来执行命令

      InputStream in = proc.getErrorStream();//得到错误信息输出。

      BufferedReader br = new BufferedReader(new InputStreamReader(in));

      String line = "";

      while ( (line = br.readLine())

             != null) {

        outInfo = outInfo + line + "\n";

        System.out.println(outInfo);

      }

      // 检查命令是否失败。

      try {

        if (proc.waitFor() != 0) {

          System.err.println("exit value = " +

                             proc.exitValue());

        }

      }

      catch (InterruptedException e) {

        System.err.print(e);

        e.printStackTrace();

      }

    }

    catch (IOException e) {

      flag = false;

      System.out.println("exec error: " + e.getMessage());

      e.printStackTrace();

    }

    finally {

      return outInfo;

    }

  }

}