Runtime.exec执行命令行程序,用户输入的问题

Question

我有一个Windows命令行程序app.exe, 运行后会提示,要求输入密码才能继续, 不能把密码当作单独的参数,一定要先执行,再打入密码...我想用Java调用这个程序,但不知如何输入密码给那个命令行程序还请大家帮忙想想办法, 
谢谢大家!
测试代码如下,执行后死机,不会显示"完成":import java.io.*;
import java.util.*;public class Test {
   static BufferedReader stdout, stderr;
   static Vector outputLines;
   public static void main(String args[]) {
       try {
           BufferedReader br;
           br = new BufferedReader(new InputStreamReader(System.in));
           StringBuffer s2 = new StringBuffer();
           String line;
           System.out.println("输入密码:");
               line = br.readLine();
               if (line != null) {
                   s2.append(line);
                   s2.append("\r\n");
               }
           Runtime r;
           r = Runtime.getRuntime();
           Process p = r.exec(app.exe);  //外部命令行程序
           System.out.println("读取输出:");
           InputStream is = p.getInputStream();
           stdout = new BufferedReader(new InputStreamReader(is));
           is = p.getErrorStream();
           stderr = new BufferedReader(new InputStreamReader(is));
           outputLines = new Vector();           Thread stdoutThread = new Thread() {
                   public void run() {
                       try {
                           int l;
                           String line;
                           for(l = 0; (line = stdout.readLine()) != null; ) {
                               if (line.length() > 0) {
                                   l++;
                                   outputLines.addElement(line);
                               }
                               System.out.println(line);
                           }
                           System.out.println("\n已读" + l);
                           stdout.close();
                       }
                       catch(IOException ie) {
                           System.out.println("IO exception: " + ie);
                       }
                   }
               };
           stdoutThread.start();           Thread stderrThread = new Thread() {
                   public void run() {
                       try {
                           int l;
                           String line;
                           for(l = 0; (line = stderr.readLine()) != null; ) {
                               if (line.length() > 0) l++;
                               System.out.print(",");
                           }
                           System.out.println("\n已读" + l);
                           stderr.close();
                       }
                       catch(IOException ie) {
                           System.out.println("IO exception: " + ie);
                       }
                   }
               };
           stderrThread.start();           OutputStream os = p.getOutputStream();
           PrintStream ps2 = new PrintStream(os);
           ps2.println(s2.toString());
           System.out.println("已输入");
           ps2.close();
           System.out.println("等待waitfor");
           p.waitFor();
           System.out.println("完成");
       }
       catch (Exception e) {
           System.out.println("Exception: " + e);
       }
   }
}

Answer 1

public Process exec(String command, String[] envp)用这个重载方法吧,在调用这个之前,自己做个询问输入:System.out.println("请输入密码");
String psw = new Scanner(System.in).nextLine();
Runtime.getRuntime().exec("app.exe", {psw});