Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
ThresholdingInputStream |
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| 2.6666666666666665;2.667 |
1 | /* | |
2 | * Licensed to the Apache Software Foundation (ASF) under one or more | |
3 | * contributor license agreements. See the NOTICE file distributed with | |
4 | * this work for additional information regarding copyright ownership. | |
5 | * The ASF licenses this file to You under the Apache License, Version 2.0 | |
6 | * (the "License"); you may not use this file except in compliance with | |
7 | * the License. You may obtain a copy of the License at | |
8 | * | |
9 | * http://www.apache.org/licenses/LICENSE-2.0 | |
10 | * | |
11 | * Unless required by applicable law or agreed to in writing, software | |
12 | * distributed under the License is distributed on an "AS IS" BASIS, | |
13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
14 | * See the License for the specific language governing permissions and | |
15 | * limitations under the License. | |
16 | */ | |
17 | package org.apache.commons.flatfile.util; | |
18 | ||
19 | import java.io.IOException; | |
20 | import java.io.InputStream; | |
21 | ||
22 | import org.apache.commons.io.input.CountingInputStream; | |
23 | ||
24 | /** | |
25 | * FilterInputStream that limits the data returned from the proxy. | |
26 | * @version $Revision: 1301244 $ $Date: 2012-03-15 17:16:23 -0500 (Thu, 15 Mar 2012) $ | |
27 | */ | |
28 | public class ThresholdingInputStream extends CountingInputStream { | |
29 | private static final int EOF = -1; | |
30 | ||
31 | private final int maximum; | |
32 | private boolean closed; | |
33 | ||
34 | /** | |
35 | * Create a new ThresholdingInputStream. | |
36 | * @param in the filtered stream | |
37 | * @param maximum length | |
38 | */ | |
39 | public ThresholdingInputStream(InputStream in, int maximum) { | |
40 | 468 | super(in); |
41 | 468 | this.maximum = maximum; |
42 | 468 | } |
43 | ||
44 | /* | |
45 | * NOTICE: implementing all three read(...) methods such that corresponding | |
46 | * super methods are called | |
47 | */ | |
48 | ||
49 | /** | |
50 | * {@inheritDoc} | |
51 | */ | |
52 | public synchronized int read() throws IOException { | |
53 | 0 | assertNotClosed(); |
54 | 0 | if (getCount() >= maximum) { |
55 | 0 | return EOF; |
56 | } | |
57 | 0 | return super.read(); |
58 | } | |
59 | ||
60 | /** | |
61 | * {@inheritDoc} | |
62 | */ | |
63 | public synchronized int read(byte[] b, int off, int len) throws IOException { | |
64 | 0 | assertNotClosed(); |
65 | 0 | int n = maximum - getCount(); |
66 | 0 | return n == 0 ? EOF : super.read(b, off, n < len ? n : len); |
67 | } | |
68 | ||
69 | /** | |
70 | * {@inheritDoc} | |
71 | */ | |
72 | public synchronized int read(byte[] b) throws IOException { | |
73 | 696 | assertNotClosed(); |
74 | 696 | int n = maximum - getCount(); |
75 | 696 | if (n == 0) { |
76 | 96 | return EOF; |
77 | } | |
78 | 600 | if (n < b.length) { |
79 | 204 | byte[] buf = new byte[n]; |
80 | 204 | System.arraycopy(b, 0, buf, 0, n); |
81 | try { | |
82 | 272 | return super.read(buf); |
83 | 0 | } finally { |
84 | 204 | System.arraycopy(buf, 0, b, 0, n); |
85 | 0 | } |
86 | } | |
87 | 396 | return super.read(b); |
88 | } | |
89 | ||
90 | /** | |
91 | * {@inheritDoc} | |
92 | */ | |
93 | public synchronized void close() throws IOException { | |
94 | 0 | this.closed = true; |
95 | 0 | super.close(); |
96 | 0 | } |
97 | ||
98 | /** | |
99 | * Make sure the stream is not closed. | |
100 | * @throws IOException if stream has been closed. | |
101 | */ | |
102 | private synchronized void assertNotClosed() throws IOException { | |
103 | 696 | if (closed) { |
104 | 0 | throw new IOException("Stream closed"); |
105 | } | |
106 | 696 | } |
107 | } |