src/uk/co/timwise/sqlhawk/util/ConsolePasswordReader.java

   1 /*
   2  * This file is a part of the SchemaSpy project (http://schemaspy.sourceforge.net).
   3  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 John Currier
   4  *
   5  * SchemaSpy is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * SchemaSpy is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  18  */
  19 package uk.co.timwise.sqlhawk.util;
  20
  21 import java.lang.reflect.InvocationTargetException;
  22 import java.lang.reflect.Method;
  23
  24 /**
  25  * Implementation of {@link PasswordReader} that takes advantage of the
  26  * built-in password reading abilities of Java6 (or higher).
  27  *
  28  * Use {@link PasswordReader#getInstance()} to get an instance of
  29  * PasswordReader that's appropriate for your JVM
  30  * (this one requires a Java6 or higher JVM).
  31  *
  32  * @author John Currier
  33  */
  34 public class ConsolePasswordReader extends PasswordReader {
  35     private final Object console;
  36     private final Method readPassword;
  37
  38     /**
  39      * Attempt to resolve the Console methods that were introduced in Java6.
  40      *
  41      * @throws SecurityException
  42      * @throws NoSuchMethodException
  43      * @throws InvocationTargetException
  44      * @throws IllegalAccessException
  45      * @throws IllegalArgumentException
  46      */
  47     protected ConsolePasswordReader() throws SecurityException, NoSuchMethodException, IllegalArgumentException, IllegalAccessException, InvocationTargetException {
  48         // get the console by calling System.console() (Java6+ method)
  49         Method consoleGetter = System.class.getMethod("console", (Class[])null);
  50         console = consoleGetter.invoke(null, (Object[])null);
  51
  52         // get Console.readPassword(String, Object[]) method
  53         Class<?>[] paramTypes = new Class<?>[] {String.class, Object[].class};
  54         readPassword = console.getClass().getMethod("readPassword", paramTypes);
  55     }
  56
  57     /**
  58      * Attempt to use the previously resolved Console.
  59      * If unable to use it then revert to the one implemented in the base class.
  60      */
  61     @Override
  62     public char[] readPassword(String fmt, Object... args) {
  63         try {
  64             return (char[])readPassword.invoke(console, fmt, args);
  65         } catch (Throwable exc) {
  66             return super.readPassword(fmt, args);
  67         }
  68     }
  69 }