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1
51 package org.apache.fop.render.ps;
52
53 import java.io.OutputStream  ;
54 import java.io.FilterOutputStream ;
55 import java.io.IOException ;
56
57
63 public class ASCII85OutputStream extends FilterOutputStream
64 implements Finalizable {
65
66 private static final int ZERO = 0x7A; private static final byte[] ZERO_ARRAY = {(byte)ZERO};
68 private static final int START = 0x21; private static final int EOL = 0x0A; private static final byte[] EOD = {0x7E, 0x3E};
72 private static final long base85_4 = 85;
73 private static final long base85_3 = base85_4 * base85_4;
74 private static final long base85_2 = base85_3 * base85_4;
75 private static final long base85_1 = base85_2 * base85_4;
76
77 private static final boolean DEBUG = false;
78
79 private int pos = 0;
80 private long buffer = 0;
81 private int posinline = 0;
82 private int bw = 0;
83
84
85 public ASCII85OutputStream(OutputStream out) {
86 super(out);
87 }
88
89
90 public void write(int b) throws IOException {
91 if (pos == 0) {
92 buffer += (b << 24) & 0xff000000L;
93 } else if (pos == 1) {
94 buffer += (b << 16) & 0xff0000L;
95 } else if (pos == 2) {
96 buffer += (b << 8) & 0xff00L;
97 } else {
98 buffer += b & 0xffL;
99 }
100 pos++;
101
102 if (pos > 3) {
103 checkedWrite(convertWord(buffer));
104 buffer = 0;
105 pos = 0;
106 }
107 }
108
109
110 private void checkedWrite(int b) throws IOException {
111 if (posinline == 80) {
112 out.write(EOL); bw++;
113 posinline = 0;
114 }
115 checkedWrite(b);
116 posinline++;
117 bw++;
118 }
119
120
121 private void checkedWrite(byte[] buf) throws IOException {
122 checkedWrite(buf, buf.length, false);
123 }
124
125
126 private void checkedWrite(byte[] buf, boolean nosplit) throws IOException {
127 checkedWrite(buf, buf.length, nosplit);
128 }
129
130
131 private void checkedWrite(byte[] buf , int len) throws IOException {
132 checkedWrite(buf, len, false);
133 }
134
135
136 private void checkedWrite(byte[] buf , int len, boolean nosplit) throws IOException {
137 if (posinline + len > 80) {
138 int firstpart = (nosplit ? 0 : len - (posinline + len - 80));
139 if (firstpart > 0) out.write(buf, 0, firstpart);
140 out.write(EOL); bw++;
141 int rest = len - firstpart;
142 if (rest > 0) out.write(buf, firstpart, rest);
143 posinline = rest;
144 } else {
145 out.write(buf, 0, len);
146 posinline += len;
147 }
148 bw += len;
149 }
150
151
152
161 private byte[] convertWord(long word) {
162 word = word & 0xffffffff;
163
164 if (word == 0) {
165 return ZERO_ARRAY;
166 } else {
167 if (word < 0) {
168 word = -word;
169 }
170 byte c1 = (byte)((word / base85_1) & 0xFF);
171 byte c2 = (byte)(((word - (c1 * base85_1)) / base85_2) & 0xFF);
172 byte c3 =
173 (byte)(((word - (c1 * base85_1) - (c2 * base85_2)) / base85_3)
174 & 0xFF);
175 byte c4 =
176 (byte)(((word - (c1 * base85_1) - (c2 * base85_2) - (c3 * base85_3)) / base85_4)
177 & 0xFF);
178 byte c5 =
179 (byte)(((word - (c1 * base85_1) - (c2 * base85_2) - (c3 * base85_3) - (c4 * base85_4)))
180 & 0xFF);
181
182 byte[] ret = {
183 (byte)(c1 + START), (byte)(c2 + START),
184 (byte)(c3 + START), (byte)(c4 + START),
185 (byte)(c5 + START)
186 };
187
188 if (DEBUG) {
189 for (int i = 0; i < ret.length; i++) {
190 if (ret[i] < 33 || ret[i] > 117) {
191 System.out.println("Illegal char value "
192 + new Integer (ret[i]));
193 }
194 }
195 }
196 return ret;
197 }
198 }
199
200
201 public void finalizeStream() throws IOException {
202 if (pos > 0) {
207 int rest = pos;
208
224
225 byte[] conv;
226 if (buffer != 0) {
228 conv = convertWord(buffer);
229 } else {
230 conv = new byte[5];
231 for (int j = 0; j < 5; j++) {
232 conv[j] = (byte)'!';
233 }
234 }
235 checkedWrite(conv, rest + 1);
237 }
238 checkedWrite(EOD, true);
240
241 flush();
242 if (out instanceof Finalizable) {
243 ((Finalizable)out).finalizeStream();
244 }
245 }
246
247
248 public void close() throws IOException {
249 finalizeStream();
250 super.close();
251 }
252
253 }
254
255
256 |
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