org/jpc/ArgProcessor.java

   1 /*
   2     JPC-RR: A x86 PC Hardware Emulator
   3     Release 1
   4
   5     Copyright (C) 2007-2009 Isis Innovation Limited
   6     Copyright (C) 2009 H. Ilari Liusvaara
   7
   8     This program is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License version 2 as published by
  10     the Free Software Foundation.
  11
  12     This program is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License along
  18     with this program; if not, write to the Free Software Foundation, Inc.,
  19     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20
  21     Based on JPC x86 PC Hardware emulator,
  22     A project from the Physics Dept, The University of Oxford
  23
  24     Details about original JPC can be found at:
  25
  26     www-jpc.physics.ox.ac.uk
  27
  28 */
  29
  30 package org.jpc;
  31
  32 /**
  33  * Provides simple command line parsing for the various frontends to the
  34  * emulator.
  35  * @author Rhys Newman
  36  */
  37 public class ArgProcessor
  38 {
  39     /**
  40      * Finds the value of the variable <code>key</code>.  Searches the given
  41      * commandline for <code>-key value</code>
  42      * @param args array of strings to search
  43      * @param key key to search for
  44      * @param defaultValue value returned on failure
  45      * @return result, or <code>defaultValue</code> on failure
  46      */
  47     public static String findVariable(String[] args, String key, String defaultValue)
  48     {
  49         int keyIndex = findKey(args, key);
  50         if(keyIndex < 0)
  51             return defaultValue;
  52
  53         if((keyIndex + 1) < args.length)
  54             return args[keyIndex + 1];
  55         else
  56             return defaultValue;
  57     }
  58
  59     /**
  60      * Searches for the presence of the given flag on the command line as
  61      * <code>-flag</code>
  62      * @param args array of strings to search
  63      * @param flag parameter to search for
  64      * @return true if flag is found
  65      */
  66     public static boolean findFlag(String[] args, String flag)
  67     {
  68         return findKey(args, flag) >= 0;
  69     }
  70
  71     private static int findKey(String[] args, String key)
  72     {
  73         if(key.startsWith("-"))
  74             key = key.substring(1);
  75
  76         for(int i=0; i<args.length; i++) {
  77             if(!args[i].startsWith("-"))
  78                 continue;
  79
  80             if(args[i].substring(1).equalsIgnoreCase(key))
  81                 return i;
  82         }
  83
  84         return -1;
  85     }
  86
  87     private ArgProcessor()
  88     {
  89     }
  90 }