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1
17 package net.sf.packtag.implementation;
18
19 import java.io.FileInputStream  ;
20 import java.io.FileNotFoundException ;
21 import java.io.IOException ;
22 import java.io.InputStream ;
23 import java.io.OutputStream ;
24 import java.io.PushbackInputStream ;
25
26
27
28
70 public class JSMin {
71
72 private static final int EOF = -1;
73
74 private PushbackInputStream in;
75
76 private OutputStream out;
77
78 private int theA;
79
80 private int theB;
81
82
83 public JSMin(InputStream in, OutputStream out) {
84 this.in = new PushbackInputStream (in);
85 this.out = out;
86 }
87
88
89
93 static boolean isAlphanum(int c) {
94 return ((c >= 'a' && c <= 'z') || (c >= '0' && c <= '9') || (c >= 'A' && c <= 'Z') || c == '_' || c == '$' || c == '\\' || c > 126);
95 }
96
97
98
103 int get() throws IOException {
104 int c = in.read();
105
106 if (c >= ' ' || c == '\n' || c == EOF) {
107 return c;
108 }
109
110 if (c == '\r') {
111 return '\n';
112 }
113
114 return ' ';
115 }
116
117
118
121 int peek() throws IOException {
122 int lookaheadChar = in.read();
123 in.unread(lookaheadChar);
124 return lookaheadChar;
125 }
126
127
128
132 int next() throws IOException , UnterminatedCommentException {
133 int c = get();
134 if (c == '/') {
135 switch (peek()) {
136 case '/':
137 for (;;) {
138 c = get();
139 if (c <= '\n') {
140 return c;
141 }
142 }
143
144 case '*':
145 get();
146 for (;;) {
147 switch (get()) {
148 case '*':
149 if (peek() == '/') {
150 get();
151 return ' ';
152 }
153 break;
154 case EOF:
155 throw new UnterminatedCommentException();
156 }
157 }
158
159 default:
160 return c;
161 }
162
163 }
164 return c;
165 }
166
167
168
175
176 void action(int d) throws IOException , UnterminatedRegExpLiteralException, UnterminatedCommentException, UnterminatedStringLiteralException {
177 switch (d) {
178 case 1:
179 out.write(theA);
180 case 2:
181 theA = theB;
182
183 if (theA == '\'' || theA == '"') {
184 for (;;) {
185 out.write(theA);
186 theA = get();
187 if (theA == theB) {
188 break;
189 }
190 if (theA <= '\n') {
191 throw new UnterminatedStringLiteralException();
192 }
193 if (theA == '\\') {
194 out.write(theA);
195 theA = get();
196 }
197 }
198 }
199
200 case 3:
201 theB = next();
202 if (theB == '/' && (theA == '(' || theA == ',' || theA == '=')) {
203 out.write(theA);
204 out.write(theB);
205 for (;;) {
206 theA = get();
207 if (theA == '/') {
208 break;
209 }
210 else if (theA == '\\') {
211 out.write(theA);
212 theA = get();
213 }
214 else if (theA <= '\n') {
215 throw new UnterminatedRegExpLiteralException();
216 }
217 out.write(theA);
218 }
219 theB = next();
220 }
221 }
222 }
223
224
225
231 public void jsmin() throws IOException , UnterminatedRegExpLiteralException, UnterminatedCommentException, UnterminatedStringLiteralException {
232 theA = '\n';
233 action(3);
234 while(theA != EOF) {
235 switch (theA) {
236 case ' ':
237 if (isAlphanum(theB)) {
238 action(1);
239 }
240 else {
241 action(2);
242 }
243 break;
244 case '\n':
245 switch (theB) {
246 case '{':
247 case '[':
248 case '(':
249 case '+':
250 case '-':
251 action(1);
252 break;
253 case ' ':
254 action(3);
255 break;
256 default:
257 if (isAlphanum(theB)) {
258 action(1);
259 }
260 else {
261 action(2);
262 }
263 }
264 break;
265 default:
266 switch (theB) {
267 case ' ':
268 if (isAlphanum(theA)) {
269 action(1);
270 break;
271 }
272 action(3);
273 break;
274 case '\n':
275 switch (theA) {
276 case '}':
277 case ']':
278 case ')':
279 case '+':
280 case '-':
281 case '"':
282 case '\'':
283 action(1);
284 break;
285 default:
286 if (isAlphanum(theA)) {
287 action(1);
288 }
289 else {
290 action(3);
291 }
292 }
293 break;
294 default:
295 action(1);
296 break;
297 }
298 }
299 }
300 out.flush();
301 }
302
303 class UnterminatedCommentException extends Exception {
304
305 private static final long serialVersionUID = 7971352218559346169L;
306 }
307
308 class UnterminatedStringLiteralException extends Exception {
309
310 private static final long serialVersionUID = 3813645314180522143L;
311 }
312
313 class UnterminatedRegExpLiteralException extends Exception {
314
315 private static final long serialVersionUID = -5088088141334641219L;
316 }
317
318
319 public static void main(String arg[]) {
320 try {
321 JSMin jsmin = new JSMin(new FileInputStream (arg[0]), System.out);
322 jsmin.jsmin();
323 }
324 catch (FileNotFoundException e) {
325 e.printStackTrace();
326 }
327 catch (ArrayIndexOutOfBoundsException e) {
328 e.printStackTrace();
329 }
330 catch (IOException e) {
331 e.printStackTrace();
332 }
333 catch (UnterminatedRegExpLiteralException e) {
334 e.printStackTrace();
335 }
336 catch (UnterminatedCommentException e) {
337 e.printStackTrace();
338 }
339 catch (UnterminatedStringLiteralException e) {
340 e.printStackTrace();
341 }
342 }
343
344 }
345 |
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