CommandLine.java revision 3261:527e819dbc95 
1/*
2 * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package com.sun.tools.javac.main;
27
28import java.io.IOException;
29import java.io.Reader;
30import java.io.StreamTokenizer;
31import java.nio.file.Files;
32import java.nio.file.Paths;
33
34import com.sun.tools.javac.util.ListBuffer;
35
36/**
37 * Various utility methods for processing Java tool command line arguments.
38 *
39 *  <p><b>This is NOT part of any supported API.
40 *  If you write code that depends on this, you do so at your own risk.
41 *  This code and its internal interfaces are subject to change or
42 *  deletion without notice.</b>
43 */
44public class CommandLine {
45    /**
46     * Process Win32-style command files for the specified command line
47     * arguments and return the resulting arguments. A command file argument
48     * is of the form '@file' where 'file' is the name of the file whose
49     * contents are to be parsed for additional arguments. The contents of
50     * the command file are parsed using StreamTokenizer and the original
51     * '@file' argument replaced with the resulting tokens. Recursive command
52     * files are not supported. The '@' character itself can be quoted with
53     * the sequence '@@'.
54     */
55    public static String[] parse(String[] args)
56        throws IOException
57    {
58        ListBuffer<String> newArgs = new ListBuffer<>();
59        for (String arg : args) {
60            if (arg.length() > 1 && arg.charAt(0) == '@') {
61                arg = arg.substring(1);
62                if (arg.charAt(0) == '@') {
63                    newArgs.append(arg);
64                } else {
65                    loadCmdFile(arg, newArgs);
66                }
67            } else {
68                newArgs.append(arg);
69            }
70        }
71        return newArgs.toList().toArray(new String[newArgs.length()]);
72    }
73
74    private static void loadCmdFile(String name, ListBuffer<String> args)
75        throws IOException
76    {
77        try (Reader r = Files.newBufferedReader(Paths.get(name))) {
78            StreamTokenizer st = new StreamTokenizer(r);
79            st.resetSyntax();
80            st.wordChars(' ', 255);
81            st.whitespaceChars(0, ' ');
82            st.commentChar('#');
83            st.quoteChar('"');
84            st.quoteChar('\'');
85            while (st.nextToken() != StreamTokenizer.TT_EOF) {
86                args.append(st.sval);
87            }
88        }
89    }
90}
91