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Java > Open Source Codes > org > columba > ristretto > io > SequenceInputStream


1 /* ***** BEGIN LICENSE BLOCK *****
2  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
3  *
4  * The contents of this file are subject to the Mozilla Public License Version
5  * 1.1 (the "License"); you may not use this file except in compliance with
6  * the License. You may obtain a copy of the License at
7  * http://www.mozilla.org/MPL/
8  *
9  * Software distributed under the License is distributed on an "AS IS" basis,
10  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
11  * for the specific language governing rights and limitations under the
12  * License.
13  *
14  * The Original Code is Ristretto Mail API.
15  *
16  * The Initial Developers of the Original Code are
17  * Timo Stich and Frederik Dietz.
18  * Portions created by the Initial Developers are Copyright (C) 2004
19  * All Rights Reserved.
20  *
21  * Contributor(s):
22  *
23  * Alternatively, the contents of this file may be used under the terms of
24  * either the GNU General Public License Version 2 or later (the "GPL"), or
25  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
26  * in which case the provisions of the GPL or the LGPL are applicable instead
27  * of those above. If you wish to allow use of your version of this file only
28  * under the terms of either the GPL or the LGPL, and not to allow others to
29  * use your version of this file under the terms of the MPL, indicate your
30  * decision by deleting the provisions above and replace them with the notice
31  * and other provisions required by the GPL or the LGPL. If you do not delete
32  * the provisions above, a recipient may use your version of this file under
33  * the terms of any one of the MPL, the GPL or the LGPL.
34  *
35  * ***** END LICENSE BLOCK ***** */
36 package org.columba.ristretto.io;
37
38 import java.io.IOException JavaDoc;
39 import java.io.InputStream JavaDoc;
40 import java.util.Arrays JavaDoc;
41 import java.util.Iterator JavaDoc;
42 import java.util.List JavaDoc;
43
44
45
46 /**
47  * An InputStream that concats InputStreams.
48  *
49  * @author Timo Stich <tstich@users.sourceforge.net>
50  */
51 public class SequenceInputStream extends InputStream JavaDoc {
52
53     List JavaDoc streams;
54     int index;
55
56     /**
57      * Construct the SequenceInputStream.
58      *
59      * @param e a list of InputStreams to concat
60      */
61     public SequenceInputStream(List JavaDoc e) {
62         streams = e;
63     }
64
65     /**
66      * Construct the SequenceInputStream.
67      *
68      * @param s1
69      * @param s2
70      */
71     public SequenceInputStream(InputStream JavaDoc s1, InputStream JavaDoc s2) {
72         streams = Arrays.asList(new InputStream JavaDoc[] {s1, s2});
73     }
74
75     /**
76      * @see java.io.InputStream#read()
77      */
78     public int read() throws IOException JavaDoc {
79         int read = ((InputStream JavaDoc)streams.get(index)).read();
80         if( read == -1 && index < streams.size()-1) {
81             index++;
82             read = ((InputStream JavaDoc)streams.get(index)).read();
83         }
84         
85         return read;
86     }
87
88     /**
89      * @see java.io.InputStream#read(byte[], int, int)
90      */
91     public int read(byte[] b, int off, int len) throws IOException JavaDoc {
92         int read = ((InputStream JavaDoc)streams.get(index)).read(b,off,len);
93         
94         while( read != len && index < streams.size()-1) {
95             if (read == -1) read = 0;
96             index++;
97             int nextread = ((InputStream JavaDoc)streams.get(index)).read(b,off+read,len-read);
98             
99             if( nextread != -1) read += nextread;
100         }
101         
102         return read;
103     }
104
105     /**
106      * @see java.io.InputStream#available()
107      */
108     public int available() throws IOException JavaDoc {
109         int size = 0;
110         for( int i=0; i<streams.size(); i++) {
111             size += ((InputStream JavaDoc)streams.get(i)).available();
112         }
113         return size;
114     }
115
116     /**
117      * @see java.io.InputStream#close()
118      */
119     public void close() throws IOException JavaDoc {
120         Iterator JavaDoc it = streams.iterator();
121         while( it.hasNext() ) {
122             ((InputStream JavaDoc) it.next()).close();
123         }
124     }
125
126 }
127
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