急急急！！用java代码远程调用linux命令为啥不出来结果啊！！！命令：java -version


代码如下：

public class ConnectUtil {

public static String cmdExcute(String value) {

String result = "";

try {

Connection conn = getConnection();

Session ssh = getSession(conn);

ssh.execCommand(value);

InputStream is = new StreamGobbler(ssh.getStdout());

BufferedReader brs = new BufferedReader(new InputStreamReader(is));

StringBuffer sb = new StringBuffer();

while (true) {

String line = brs.readLine();

if (line == null) {

break;

}

sb.append(line);

}

result = sb.toString();

closeConnection(conn, ssh);

} catch (IOException e) {

e.printStackTrace();

}

return result;

}

public static void main(String[] args){

System.out.println(ConnectUtil.cmdExcute("java -version"));

}

}