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1
15
16 package javassist.preproc;
17
18 import java.io.IOException  ;
19 import java.io.BufferedReader ;
20 import java.io.FileReader ;
21 import java.io.BufferedWriter ;
22 import java.io.FileWriter ;
23 import java.util.Vector ;
24 import javassist.CannotCompileException;
25 import javassist.CtClass;
26 import javassist.ClassPool;
27
28
51
52 public class Compiler {
53 protected BufferedReader input;
54 protected BufferedWriter output;
55 protected ClassPool classPool;
56
57
62 public Compiler(String inputname) throws CannotCompileException {
63 try {
64 input = new BufferedReader (new FileReader (inputname));
65 }
66 catch (IOException e) {
67 throw new CannotCompileException("cannot open: " + inputname);
68 }
69
70 String outputname = getOutputFilename(inputname);
71 if (outputname.equals(inputname))
72 throw new CannotCompileException("invalid source name: "
73 + inputname);
74
75 try {
76 output = new BufferedWriter (new FileWriter (outputname));
77 }
78 catch (IOException e) {
79 throw new CannotCompileException("cannot open: " + outputname);
80 }
81
82 classPool = ClassPool.getDefault();
83 }
84
85
88 public void process() throws IOException , CannotCompileException {
89 int c;
90 CommentSkipper reader = new CommentSkipper(input, output);
91 while ((c = reader.read()) != -1) {
92 output.write(c);
93 if (c == 'p') {
94 if (skipPackage(reader))
95 break;
96 }
97 else if (c == 'i')
98 readImport(reader);
99 else if (c != ' ' && c != '\t' && c != '\n' && c != '\r')
100 break;
101 }
102
103 while ((c = input.read()) != -1)
104 output.write(c);
105
106 input.close();
107 output.close();
108 }
109
110 private boolean skipPackage(CommentSkipper reader) throws IOException {
111 int c;
112 c = reader.read();
113 output.write(c);
114 if (c != 'a')
115 return true;
116
117 while ((c = reader.read()) != -1) {
118 output.write(c);
119 if (c == ';')
120 break;
121 }
122
123 return false;
124 }
125
126 private void readImport(CommentSkipper reader)
127 throws IOException , CannotCompileException
128 {
129 int word[] = new int[5];
130 int c;
131 for (int i = 0; i < 5; ++i) {
132 word[i] = reader.read();
133 output.write(word[i]);
134 }
135
136 if (word[0] != 'm' || word[1] != 'p' || word[2] != 'o'
137 || word[3] != 'r' || word[4] != 't')
138 return;
140 c = skipSpaces(reader, ' ');
141 StringBuffer classbuf = new StringBuffer ();
142 while (c != ' ' && c != '\t' && c != '\n' && c != '\r'
143 && c != ';' && c != -1) {
144 classbuf.append((char)c);
145 c = reader.read();
146 }
147
148 String importclass = classbuf.toString();
149 c = skipSpaces(reader, c);
150 if (c == ';') {
151 output.write(importclass);
152 output.write(';');
153 return;
154 }
155 if (c != 'b')
156 syntaxError(importclass);
157
158 reader.read();
160 StringBuffer assistant = new StringBuffer ();
161 Vector args = new Vector ();
162 c = readAssistant(reader, importclass, assistant, args);
163 c = skipSpaces(reader, c);
164 if (c != ';')
165 syntaxError(importclass);
166
167 runAssistant(importclass, assistant.toString(), args);
168 }
169
170 void syntaxError(String importclass) throws CannotCompileException {
171 throw new CannotCompileException("Syntax error. Cannot import "
172 + importclass);
173 }
174
175 int readAssistant(CommentSkipper reader, String importclass,
176 StringBuffer assistant, Vector args)
177 throws IOException , CannotCompileException
178 {
179 int c = readArgument(reader, assistant);
180 c = skipSpaces(reader, c);
181 if (c == '(') {
182 do {
183 StringBuffer arg = new StringBuffer ();
184 c = readArgument(reader, arg);
185 args.addElement(arg.toString());
186 c = skipSpaces(reader, c);
187 } while (c == ',');
188
189 if (c != ')')
190 syntaxError(importclass);
191
192 return reader.read();
193 }
194
195 return c;
196 }
197
198 int readArgument(CommentSkipper reader, StringBuffer buf)
199 throws IOException
200 {
201 int c = skipSpaces(reader, ' ');
202 while ('A' <= c && c <= 'Z' || 'a' <= c && c <= 'z'
203 || '0' <= c && c <= '9' || c == '.' || c == '_') {
204 buf.append((char)c);
205 c = reader.read();
206 }
207
208 return c;
209 }
210
211 int skipSpaces(CommentSkipper reader, int c) throws IOException {
212 while (c == ' ' || c == '\t' || c == '\n' || c == '\r') {
213 if (c == '\n' || c == '\r')
214 output.write(c);
215
216 c = reader.read();
217 }
218
219 return c;
220 }
221
222
233 private void runAssistant(String importname, String assistantname,
234 Vector argv)
235 throws IOException , CannotCompileException
236 {
237 Class assistant;
238 Assistant a;
239 int s = argv.size();
240 String [] args = new String [s];
241 for (int i = 0; i < s; ++i)
242 args[i] = (String )argv.elementAt(i);
243
244 try {
245 assistant = Class.forName(assistantname);
246 }
247 catch (ClassNotFoundException e) {
248 throw new CannotCompileException("Cannot find " + assistantname);
249 }
250
251 try {
252 a = (Assistant)assistant.newInstance();
253 }
254 catch (Exception e) {
255 throw new CannotCompileException(e);
256 }
257
258 CtClass[] imports = a.assist(classPool, importname, args);
259 s = imports.length;
260 if (s < 1)
261 output.write(" java.lang.Object;");
262 else {
263 output.write(' ');
264 output.write(imports[0].getName());
265 output.write(';');
266 for (int i = 1; i < s; ++i) {
267 output.write(" import ");
268 output.write(imports[1].getName());
269 output.write(';');
270 }
271 }
272 }
273
274 private String getOutputFilename(String input) {
275 int i = input.lastIndexOf('.');
276 if (i < 0)
277 i = input.length();
278
279 return input.substring(0, i) + ".java";
280 }
281
282 public static void main(String [] args) {
283 if (args.length > 0)
284 try {
285 Compiler c = new Compiler (args[0]);
286 c.process();
287 }
288 catch (IOException e) {
289 System.err.println(e);
290 }
291 catch (CannotCompileException e) {
292 System.err.println(e);
293 }
294 else {
295 System.err.println("Javassist version " + CtClass.version);
296 System.err.println("No source file is specified.");
297 }
298 }
299 }
300
301 class CommentSkipper {
302 private BufferedReader input;
303 private BufferedWriter output;
304
305 public CommentSkipper(BufferedReader reader, BufferedWriter writer) {
306 input = reader;
307 output = writer;
308 }
309
310 public int read() throws IOException {
311 int c;
312 while ((c = input.read()) != -1)
313 if (c != '/')
314 return c;
315 else {
316 c = input.read();
317 if (c == '/')
318 skipCxxComments();
319 else if (c == '*')
320 skipCComments();
321 else
322 output.write('/');
323 }
324
325 return c;
326 }
327
328 private void skipCxxComments() throws IOException {
329 int c;
330 output.write("//");
331 while ((c = input.read()) != -1) {
332 output.write(c);
333 if (c == '\n' || c == '\r')
334 break;
335 }
336 }
337
338 private void skipCComments() throws IOException {
339 int c;
340 boolean star = false;
341 output.write("/*");
342 while ((c = input.read()) != -1) {
343 output.write(c);
344 if (c == '*')
345 star = true;
346 else if(star && c == '/')
347 break;
348 else
349 star = false;
350 }
351 }
352 }
353 |
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