java在指定目录下执行dos命令或者bat文件

public static void main(String[] args) throws IOException {
		File dir = new File("D:\");
		// String command="netstat -an";
		String command = "c:\windows\system32\cmd.exe /c netstat -an";
		Runtime r = Runtime.getRuntime();
		Process p = r.exec(command, null, dir);
		BufferedReader br = new BufferedReader(new InputStreamReader(p
				.getInputStream()));
		StringBuffer sb = new StringBuffer();
		String inline;
		while (null != (inline = br.readLine())) {
			sb.append(inline).append("n");
		}
		System.out.println(sb.toString());
	}