从控制台读取密码，而不回显字符。

/*-

 * Copyright (C) 2014 Erik Larsson

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */
 /**
 nowjava - 时  代  Java 提供 
 **/

//package com.nowjava;

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;


public class Main {

    /**

     * Read password from console without echoing characters.

     *

     * @return <code>null</code> if there is no console or end of stream is

     * reached when attempting to read password.

     */

    public static char[] readPassword() {

        try {

            final Method systemConsoleMethod = java.lang.System.class

                    .getMethod("console");

            final Object consoleObject = systemConsoleMethod.invoke(null);

            if (consoleObject == null) {

                /* No console. */

                return null;

            }


            final Class<? extends Object> consoleClass = Class

                    .forName("java.io.Console");
                    /**
                     from
                    * nowjava - 时代Java 
                    **/

            final Method consoleReadPasswordMethod = consoleClass

                    .getMethod("readPassword");


            final Object passwordObject = consoleReadPasswordMethod

                    .invoke(consoleObject);

            if (passwordObject != null

                    && !(passwordObject instanceof char[])) {

                throw new RuntimeException("Unexpected type returned from "

                        + "java.io.Console.readPassword(): "

                        + passwordObject.getClass().getName());

            }


            return (char[]) passwordObject;

        } catch (ClassNotFoundException ex) {

            throw new RuntimeException(ex);

        } catch (NoSuchMethodException ex) {

            throw