Apachecommonexec执行外部命令

        String pl_cmd = "cmd.exe /c dir";
        Process p_pl = Runtime.getRuntime().exec(pl_cmd);
        BufferedReader br_pl = new BufferedReader(new InputStreamReader(
                p_pl.getInputStream()));
        String stdout = br_pl.readLine();
        while (stdout != null) {
            System.out.println(stdout);
            stdout = br_pl.readLine();
        }

        ByteArrayOutputStream stdout = new ByteArrayOutputStream();
        PumpStreamHandler psh = new PumpStreamHandler(stdout);
        CommandLine cl = CommandLine.parse("cmd.exe /c dir");
        DefaultExecutor exec = new DefaultExecutor();
        exec.setStreamHandler(psh);
        exec.execute(cl);
        System.out.println(stdout.toString());