缓冲读卡器冻结但不例外

Question

private static void runner() {
    try
    {
        Runtime rt = Runtime.getRuntime();

        //Runtime rt = Runtime();
        //rt.getRuntime();

        String command = "C:\\dummy.exe";
        //command = "cmd";
        Process pr = rt.exec(command);

        BufferedReader processOutput = new BufferedReader(new InputStreamReader(pr.getInputStream()));
        BufferedWriter processInput = new BufferedWriter(new OutputStreamWriter(pr.getOutputStream()));
        String commandToSend;
        //commandToSend = "dir\n";

        Scanner reader = new Scanner(System.in);  // Reading from System.in
        System.out.println("Enter a command");
        commandToSend = reader.nextLine(); // Scans the next token of the input as an int.

        System.out.println(commandToSend);
        processInput.write(commandToSend+"\r\n");
        processInput.flush();
        int lineCounter = 0;
        String line ="";
        boolean go2 =true;
        while(go2)
        {
               line = processOutput.readLine();
        //System.out.println("2");  

            if(line == null) {
                System.out.println("\n\ndone\n");
                go2=false;
            }


            //System.out.println(go2);
            System.out.println(++lineCounter + ": " + line); 
        }
        }
        reader.close();
        processInput.close();
        processOutput.close();
        pr.waitFor();
        System.out.println("done\n");
    }
    catch(Exception x)
    {
        x.printStackTrace();
    }
}

这是输出

Enter a command
dir
dir

3: 
12: 02/03/2018  02:35 PM               301 .classpath
13: 02/03/2018  02:35 PM               382 .project
14: 02/03/2018  02:35 PM    <DIR>          .settings
15:
16: 02/03/2018  02:36 PM    <DIR>          src
17:                2 File(s)            683 bytes
18:               5 Dir(s)  702,993,940,480 bytes free
19: 

它冻结在这里^ 它在线条处冻结= processOutput.readline（） 我尝试了多个打印语句，发现在第19行之后它会冻结，但不会引发错误。 我认为这个问题必须解决缓冲空值的问题 我已经剪了一些解释数字差距的输出 但要说明的主要内容是它不会冻结换行符 就在最后