KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > com > mchange > v2 > io > DirectoryDescentUtils


1 /*
2  * Distributed as part of debuggen v.0.1.0
3  *
4  * Copyright (C) 2005 Machinery For Change, Inc.
5  *
6  * Author: Steve Waldman <swaldman@mchange.com>
7  *
8  * This library is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU Lesser General Public License version 2.1, as
10  * published by the Free Software Foundation.
11  *
12  * This software 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 Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public License
18  * along with this software; see the file LICENSE. If not, write to the
19  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
20  * Boston, MA 02111-1307, USA.
21  */
22
23
24 package com.mchange.v2.io;
25
26 import java.io.*;
27 import java.util.*;
28
29 public final class DirectoryDescentUtils
30 {
31     /**
32      * @return FileIterator over all files and dierctories beneath root
33      */
34     public static FileIterator depthFirstEagerDescent(File root)
35     throws IOException
36     { return depthFirstEagerDescent( root, null, false ); }
37
38     /**
39      * @return FileIterator over all files and directories beneath root that
40      * match filter.
41      *
42      * @param canonical file paths will be canonicalized if true
43      */
44     public static FileIterator depthFirstEagerDescent(File root,
45                               FileFilter filter,
46                               boolean canonical)
47     throws IOException
48     {
49     List list = new LinkedList();
50     Set seenDirex = new HashSet();
51     depthFirstEagerDescend(root, filter, canonical, list, seenDirex);
52     return new IteratorFileIterator( list.iterator() );
53     }
54
55     public static void addSubtree( File root, FileFilter filter, boolean canonical, Collection addToMe ) throws IOException
56     {
57     Set seenDirex = new HashSet();
58     depthFirstEagerDescend(root, filter, canonical, addToMe, seenDirex);
59     }
60
61     private static void depthFirstEagerDescend(File dir, FileFilter filter, boolean canonical,
62                            Collection addToMe, Set seenDirex)
63     throws IOException
64     {
65     String JavaDoc canonicalPath = dir.getCanonicalPath();
66     if (! seenDirex.contains( canonicalPath ) )
67         {
68         if ( filter == null || filter.accept( dir ) )
69             addToMe.add( canonical ? new File( canonicalPath ) : dir );
70         seenDirex.add( canonicalPath );
71         String JavaDoc[] babies = dir.list();
72         for (int i = 0, len = babies.length; i < len; ++i)
73             {
74             File baby = new File(dir, babies[i]);
75             if (baby.isDirectory())
76                 depthFirstEagerDescend(baby, filter, canonical, addToMe, seenDirex);
77             else
78                 if ( filter == null || filter.accept( baby ) )
79                 addToMe.add( canonical ? baby.getCanonicalFile() : baby );
80             }
81         }
82     }
83
84     private static class IteratorFileIterator implements FileIterator
85     {
86     Iterator ii;
87     Object JavaDoc last;
88
89     IteratorFileIterator(Iterator ii)
90     { this.ii = ii; }
91
92     public File nextFile() throws IOException
93     { return (File) next(); }
94
95     public boolean hasNext() throws IOException
96     { return ii.hasNext(); }
97
98     public Object JavaDoc next() throws IOException
99     { return (last = ii.next()); }
100
101     public void remove() throws IOException
102     {
103         if (last != null)
104         {
105             ((File) last).delete();
106             last = null;
107         }
108         else
109         throw new IllegalStateException JavaDoc();
110     }
111
112     public void close() throws IOException
113     {}
114     }
115
116     private DirectoryDescentUtils()
117     {}
118
119     public static void main(String JavaDoc[] argv)
120     {
121     try
122         {
123         FileIterator fii = depthFirstEagerDescent( new File(argv[0]) );
124         while (fii.hasNext())
125             System.err.println( fii.nextFile().getPath() );
126         }
127     catch (Exception JavaDoc e)
128         { e.printStackTrace(); }
129     }
130 }
131
Popular Tags