DictionaryNameFactory.java revision b72c5c2e5482cf10117b2b25f642f7616b2326c3 
1/*
2 * ProGuard -- shrinking, optimization, obfuscation, and preverification
3 *             of Java bytecode.
4 *
5 * Copyright (c) 2002-2009 Eric Lafortune (eric@graphics.cornell.edu)
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the Free
9 * Software Foundation; either version 2 of the License, or (at your option)
10 * any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * 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 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21package proguard.obfuscate;
22
23import java.io.*;
24import java.util.*;
25
26/**
27 * This <code>NameFactory</code> generates names that are read from a
28 * specified input file.
29 * Comments (everything starting with '#' on a single line) are ignored.
30 *
31 * @author Eric Lafortune
32 */
33public class DictionaryNameFactory implements NameFactory
34{
35    private static final char COMMENT_CHARACTER = '#';
36
37
38    private final List        names;
39    private final NameFactory nameFactory;
40
41    private int index = 0;
42
43
44    /**
45     * Creates a new <code>DictionaryNameFactory</code>.
46     * @param file        the file from which the names can be read.
47     * @param nameFactory the name factory from which names will be retrieved
48     *                    if the list of read names has been exhausted.
49     */
50    public DictionaryNameFactory(File        file,
51                                 NameFactory nameFactory) throws IOException
52    {
53        this.names       = new ArrayList();
54        this.nameFactory = nameFactory;
55
56        Reader reader = new FileReader(file);
57
58        try
59        {
60            StringBuffer buffer = new StringBuffer();
61
62            while (true)
63            {
64                // Read the next character.
65                int c = reader.read();
66
67                // Is it a valid identifier character?
68                if (c != -1 &&
69                    (buffer.length() == 0 ?
70                         Character.isJavaIdentifierStart((char)c) :
71                         Character.isJavaIdentifierPart((char)c)))
72                {
73                    // Append it to the current identifier.
74                    buffer.append((char)c);
75                }
76                else
77                {
78                    // Did we collect a new identifier?
79                    if (buffer.length() > 0)
80                    {
81                        // Add the completed name to the list of names, if it's
82                        // not in it yet.
83                        String name = buffer.toString();
84                        if (!names.contains(name))
85                        {
86                            names.add(name);
87                        }
88
89                        // Clear the buffer.
90                        buffer.setLength(0);
91                    }
92
93                    // Is this the beginning of a comment line?
94                    if (c == COMMENT_CHARACTER)
95                    {
96                        // Skip all characters till the end of the line.
97                        do
98                        {
99                            c = reader.read();
100                        }
101                        while (c != -1 &&
102                               c != '\n' &&
103                               c != '\r');
104                    }
105
106                    // Is this the end of the file?
107                    if (c == -1)
108                    {
109                        // Just return.
110                        return;
111                    }
112                }
113            }
114        }
115        finally
116        {
117            reader.close();
118        }
119    }
120
121
122    /**
123     * Creates a new <code>DictionaryNameFactory</code>.
124     * @param dictionaryNameFactory the dictionary name factory whose dictionary
125     *                              will be used.
126     * @param nameFactory           the name factory from which names will be
127     *                              retrieved if the list of read names has been
128     *                              exhausted.
129     */
130    public DictionaryNameFactory(DictionaryNameFactory dictionaryNameFactory,
131                                 NameFactory           nameFactory)
132    {
133        this.names       = dictionaryNameFactory.names;
134        this.nameFactory = nameFactory;
135    }
136
137
138    // Implementations for NameFactory.
139
140    public void reset()
141    {
142        index = 0;
143
144        nameFactory.reset();
145    }
146
147
148    public String nextName()
149    {
150        String name;
151
152        // Do we still have names?
153        if (index < names.size())
154        {
155            // Return the next name.
156            name = (String)names.get(index++);
157        }
158        else
159        {
160            // Return the next different name from the other name factory.
161            do
162            {
163                name = nameFactory.nextName();
164            }
165            while (names.contains(name));
166        }
167
168        return name;
169    }
170
171
172    public static void main(String[] args)
173    {
174        try
175        {
176            DictionaryNameFactory factory =
177                new DictionaryNameFactory(new File(args[0]), new SimpleNameFactory());
178
179            for (int counter = 0; counter < 50; counter++)
180            {
181                System.out.println("["+factory.nextName()+"]");
182            }
183        }
184        catch (IOException ex)
185        {
186            ex.printStackTrace();
187        }
188    }
189}
190