1 | /*
|
---|
2 | * SimpleOutputStream
|
---|
3 | *
|
---|
4 | * Author: Lasse Collin <lasse.collin@tukaani.org>
|
---|
5 | *
|
---|
6 | * This file has been put into the public domain.
|
---|
7 | * You can do whatever you want with this file.
|
---|
8 | */
|
---|
9 |
|
---|
10 | package org.tukaani.xz;
|
---|
11 |
|
---|
12 | import java.io.IOException;
|
---|
13 | import org.tukaani.xz.simple.SimpleFilter;
|
---|
14 |
|
---|
15 | class SimpleOutputStream extends FinishableOutputStream {
|
---|
16 | private static final int FILTER_BUF_SIZE = 4096;
|
---|
17 |
|
---|
18 | private FinishableOutputStream out;
|
---|
19 | private final SimpleFilter simpleFilter;
|
---|
20 |
|
---|
21 | private final byte[] filterBuf = new byte[FILTER_BUF_SIZE];
|
---|
22 | private int pos = 0;
|
---|
23 | private int unfiltered = 0;
|
---|
24 |
|
---|
25 | private IOException exception = null;
|
---|
26 | private boolean finished = false;
|
---|
27 |
|
---|
28 | private final byte[] tempBuf = new byte[1];
|
---|
29 |
|
---|
30 | static int getMemoryUsage() {
|
---|
31 | return 1 + FILTER_BUF_SIZE / 1024;
|
---|
32 | }
|
---|
33 |
|
---|
34 | SimpleOutputStream(FinishableOutputStream out,
|
---|
35 | SimpleFilter simpleFilter) {
|
---|
36 | if (out == null)
|
---|
37 | throw new NullPointerException();
|
---|
38 |
|
---|
39 | this.out = out;
|
---|
40 | this.simpleFilter = simpleFilter;
|
---|
41 | }
|
---|
42 |
|
---|
43 | public void write(int b) throws IOException {
|
---|
44 | tempBuf[0] = (byte)b;
|
---|
45 | write(tempBuf, 0, 1);
|
---|
46 | }
|
---|
47 |
|
---|
48 | public void write(byte[] buf, int off, int len) throws IOException {
|
---|
49 | if (off < 0 || len < 0 || off + len < 0 || off + len > buf.length)
|
---|
50 | throw new IndexOutOfBoundsException();
|
---|
51 |
|
---|
52 | if (exception != null)
|
---|
53 | throw exception;
|
---|
54 |
|
---|
55 | if (finished)
|
---|
56 | throw new XZIOException("Stream finished or closed");
|
---|
57 |
|
---|
58 | while (len > 0) {
|
---|
59 | // Copy more unfiltered data into filterBuf.
|
---|
60 | int copySize = Math.min(len, FILTER_BUF_SIZE - (pos + unfiltered));
|
---|
61 | System.arraycopy(buf, off, filterBuf, pos + unfiltered, copySize);
|
---|
62 | off += copySize;
|
---|
63 | len -= copySize;
|
---|
64 | unfiltered += copySize;
|
---|
65 |
|
---|
66 | // Filter the data in filterBuf.
|
---|
67 | int filtered = simpleFilter.code(filterBuf, pos, unfiltered);
|
---|
68 | assert filtered <= unfiltered;
|
---|
69 | unfiltered -= filtered;
|
---|
70 |
|
---|
71 | // Write out the filtered data.
|
---|
72 | try {
|
---|
73 | out.write(filterBuf, pos, filtered);
|
---|
74 | } catch (IOException e) {
|
---|
75 | exception = e;
|
---|
76 | throw e;
|
---|
77 | }
|
---|
78 |
|
---|
79 | pos += filtered;
|
---|
80 |
|
---|
81 | // If end of filterBuf was reached, move the pending unfiltered
|
---|
82 | // data to the beginning of the buffer so that more data can
|
---|
83 | // be copied into filterBuf on the next loop iteration.
|
---|
84 | if (pos + unfiltered == FILTER_BUF_SIZE) {
|
---|
85 | System.arraycopy(filterBuf, pos, filterBuf, 0, unfiltered);
|
---|
86 | pos = 0;
|
---|
87 | }
|
---|
88 | }
|
---|
89 | }
|
---|
90 |
|
---|
91 | private void writePending() throws IOException {
|
---|
92 | assert !finished;
|
---|
93 |
|
---|
94 | if (exception != null)
|
---|
95 | throw exception;
|
---|
96 |
|
---|
97 | try {
|
---|
98 | out.write(filterBuf, pos, unfiltered);
|
---|
99 | } catch (IOException e) {
|
---|
100 | exception = e;
|
---|
101 | throw e;
|
---|
102 | }
|
---|
103 |
|
---|
104 | finished = true;
|
---|
105 | }
|
---|
106 |
|
---|
107 | public void flush() throws IOException {
|
---|
108 | throw new UnsupportedOptionsException("Flushing is not supported");
|
---|
109 | }
|
---|
110 |
|
---|
111 | public void finish() throws IOException {
|
---|
112 | if (!finished) {
|
---|
113 | // If it fails, don't call out.finish().
|
---|
114 | writePending();
|
---|
115 |
|
---|
116 | try {
|
---|
117 | out.finish();
|
---|
118 | } catch (IOException e) {
|
---|
119 | exception = e;
|
---|
120 | throw e;
|
---|
121 | }
|
---|
122 | }
|
---|
123 | }
|
---|
124 |
|
---|
125 | public void close() throws IOException {
|
---|
126 | if (out != null) {
|
---|
127 | if (!finished) {
|
---|
128 | // out.close() must be called even if writePending() fails.
|
---|
129 | // writePending() saves the possible exception so we can
|
---|
130 | // ignore exceptions here.
|
---|
131 | try {
|
---|
132 | writePending();
|
---|
133 | } catch (IOException e) {}
|
---|
134 | }
|
---|
135 |
|
---|
136 | try {
|
---|
137 | out.close();
|
---|
138 | } catch (IOException e) {
|
---|
139 | // If there is an earlier exception, the exception
|
---|
140 | // from out.close() is lost.
|
---|
141 | if (exception == null)
|
---|
142 | exception = e;
|
---|
143 | }
|
---|
144 |
|
---|
145 | out = null;
|
---|
146 | }
|
---|
147 |
|
---|
148 | if (exception != null)
|
---|
149 | throw exception;
|
---|
150 | }
|
---|
151 | }
|
---|