1 /*
2 * Copyright (c) 2009, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.util;
27
28 import java.io.ByteArrayOutputStream;
29 import java.io.Closeable;
30 import java.io.IOException;
31 import java.io.InputStream;
32 import java.io.OutputStreamWriter;
33 import java.lang.ref.SoftReference;
34 import java.lang.reflect.Constructor;
35 import java.net.URL;
36 import java.net.URLClassLoader;
37 import java.nio.ByteBuffer;
38 import java.nio.CharBuffer;
39 import java.nio.charset.Charset;
40 import java.nio.charset.CharsetDecoder;
41 import java.nio.charset.CoderResult;
42 import java.nio.charset.CodingErrorAction;
43 import java.nio.charset.IllegalCharsetNameException;
44 import java.nio.charset.UnsupportedCharsetException;
45 import java.util.Collection;
46 import java.util.HashMap;
47 import java.util.Iterator;
48 import java.util.Map;
49 import java.util.Set;
50 import javax.tools.JavaFileObject;
51 import javax.tools.JavaFileObject.Kind;
52
53 import com.sun.tools.javac.code.Lint;
54 import com.sun.tools.javac.code.Source;
55 import com.sun.tools.javac.file.FSInfo;
56 import com.sun.tools.javac.file.Locations;
57 import com.sun.tools.javac.main.Option;
58 import com.sun.tools.javac.main.OptionHelper;
59 import com.sun.tools.javac.main.OptionHelper.GrumpyHelper;
60 import com.sun.tools.javac.util.JCDiagnostic.SimpleDiagnosticPosition;
61
62 /**
63 * Utility methods for building a filemanager.
64 * There are no references here to file-system specific objects such as
65 * java.io.File or java.nio.file.Path.
66 */
67 public abstract class BaseFileManager {
68 protected BaseFileManager(Charset charset) {
69 this.charset = charset;
70 byteBufferCache = new ByteBufferCache();
71 locations = createLocations();
72 }
73
74 /**
75 * Set the context for JavacPathFileManager.
76 */
77 public void setContext(Context context) {
78 log = Log.instance(context);
79 options = Options.instance(context);
80 classLoaderClass = options.get("procloader");
81 locations.update(log, options, Lint.instance(context), FSInfo.instance(context));
82 }
83
84 protected Locations createLocations() {
85 return new Locations();
86 }
87
88 /**
89 * The log to be used for error reporting.
90 */
91 public Log log;
92
93 /**
94 * User provided charset (through javax.tools).
95 */
96 protected Charset charset;
97
98 protected Options options;
99
100 protected String classLoaderClass;
101
102 protected Locations locations;
103
104 protected Source getSource() {
105 String sourceName = options.get(Option.SOURCE);
106 Source source = null;
107 if (sourceName != null)
108 source = Source.lookup(sourceName);
109 return (source != null ? source : Source.DEFAULT);
110 }
111
112 protected ClassLoader getClassLoader(URL[] urls) {
113 ClassLoader thisClassLoader = getClass().getClassLoader();
114
115 // Bug: 6558476
116 // Ideally, ClassLoader should be Closeable, but before JDK7 it is not.
117 // On older versions, try the following, to get a closeable classloader.
118
119 // 1: Allow client to specify the class to use via hidden option
120 if (classLoaderClass != null) {
121 try {
122 Class<? extends ClassLoader> loader =
123 Class.forName(classLoaderClass).asSubclass(ClassLoader.class);
124 Class<?>[] constrArgTypes = { URL[].class, ClassLoader.class };
125 Constructor<? extends ClassLoader> constr = loader.getConstructor(constrArgTypes);
126 return constr.newInstance(new Object[] { urls, thisClassLoader });
127 } catch (Throwable t) {
128 // ignore errors loading user-provided class loader, fall through
129 }
130 }
131
132 // 2: If URLClassLoader implements Closeable, use that.
133 if (Closeable.class.isAssignableFrom(URLClassLoader.class))
134 return new URLClassLoader(urls, thisClassLoader);
135
136 // 3: Try using private reflection-based CloseableURLClassLoader
137 try {
138 return new CloseableURLClassLoader(urls, thisClassLoader);
139 } catch (Throwable t) {
140 // ignore errors loading workaround class loader, fall through
141 }
142
143 // 4: If all else fails, use plain old standard URLClassLoader
144 return new URLClassLoader(urls, thisClassLoader);
145 }
146
147 // <editor-fold defaultstate="collapsed" desc="Option handling">
148 public boolean handleOption(String current, Iterator<String> remaining) {
149 OptionHelper helper = new GrumpyHelper(log) {
150 @Override
151 public String get(Option option) {
152 return options.get(option.getText());
153 }
154
155 @Override
156 public void put(String name, String value) {
157 options.put(name, value);
158 }
159
160 @Override
161 public void remove(String name) {
162 options.remove(name);
163 }
164 };
165 for (Option o: javacFileManagerOptions) {
166 if (o.matches(current)) {
167 if (o.hasArg()) {
168 if (remaining.hasNext()) {
169 if (!o.process(helper, current, remaining.next()))
170 return true;
171 }
172 } else {
173 if (!o.process(helper, current))
174 return true;
175 }
176 // operand missing, or process returned false
177 throw new IllegalArgumentException(current);
178 }
179 }
180
181 return false;
182 }
183 // where
184 private static final Set<Option> javacFileManagerOptions =
185 Option.getJavacFileManagerOptions();
186
187 public int isSupportedOption(String option) {
188 for (Option o : javacFileManagerOptions) {
189 if (o.matches(option))
190 return o.hasArg() ? 1 : 0;
191 }
192 return -1;
193 }
194
195 public abstract boolean isDefaultBootClassPath();
196
197 // </editor-fold>
198
199 // <editor-fold defaultstate="collapsed" desc="Encoding">
200 private String defaultEncodingName;
201 private String getDefaultEncodingName() {
202 if (defaultEncodingName == null) {
203 defaultEncodingName =
204 new OutputStreamWriter(new ByteArrayOutputStream()).getEncoding();
205 }
206 return defaultEncodingName;
207 }
208
209 public String getEncodingName() {
210 String encName = options.get(Option.ENCODING);
211 if (encName == null)
212 return getDefaultEncodingName();
213 else
214 return encName;
215 }
216
217 public CharBuffer decode(ByteBuffer inbuf, boolean ignoreEncodingErrors) {
218 String encodingName = getEncodingName();
219 CharsetDecoder decoder;
220 try {
221 decoder = getDecoder(encodingName, ignoreEncodingErrors);
222 } catch (IllegalCharsetNameException e) {
223 log.error("unsupported.encoding", encodingName);
224 return (CharBuffer)CharBuffer.allocate(1).flip();
225 } catch (UnsupportedCharsetException e) {
226 log.error("unsupported.encoding", encodingName);
227 return (CharBuffer)CharBuffer.allocate(1).flip();
228 }
229
230 // slightly overestimate the buffer size to avoid reallocation.
231 float factor =
232 decoder.averageCharsPerByte() * 0.8f +
233 decoder.maxCharsPerByte() * 0.2f;
234 CharBuffer dest = CharBuffer.
235 allocate(10 + (int)(inbuf.remaining()*factor));
236
237 while (true) {
238 CoderResult result = decoder.decode(inbuf, dest, true);
239 dest.flip();
240
241 if (result.isUnderflow()) { // done reading
242 // make sure there is at least one extra character
243 if (dest.limit() == dest.capacity()) {
244 dest = CharBuffer.allocate(dest.capacity()+1).put(dest);
245 dest.flip();
246 }
247 return dest;
248 } else if (result.isOverflow()) { // buffer too small; expand
249 int newCapacity =
250 10 + dest.capacity() +
251 (int)(inbuf.remaining()*decoder.maxCharsPerByte());
252 dest = CharBuffer.allocate(newCapacity).put(dest);
253 } else if (result.isMalformed() || result.isUnmappable()) {
254 // bad character in input
255
256 // report coding error (warn only pre 1.5)
257 if (!getSource().allowEncodingErrors()) {
258 log.error(new SimpleDiagnosticPosition(dest.limit()),
259 "illegal.char.for.encoding",
260 charset == null ? encodingName : charset.name());
261 } else {
262 log.warning(new SimpleDiagnosticPosition(dest.limit()),
263 "illegal.char.for.encoding",
264 charset == null ? encodingName : charset.name());
265 }
266
267 // skip past the coding error
268 inbuf.position(inbuf.position() + result.length());
269
270 // undo the flip() to prepare the output buffer
271 // for more translation
272 dest.position(dest.limit());
273 dest.limit(dest.capacity());
274 dest.put((char)0xfffd); // backward compatible
275 } else {
276 throw new AssertionError(result);
277 }
278 }
279 // unreached
280 }
281
282 public CharsetDecoder getDecoder(String encodingName, boolean ignoreEncodingErrors) {
283 Charset cs = (this.charset == null)
284 ? Charset.forName(encodingName)
285 : this.charset;
286 CharsetDecoder decoder = cs.newDecoder();
287
288 CodingErrorAction action;
289 if (ignoreEncodingErrors)
290 action = CodingErrorAction.REPLACE;
291 else
292 action = CodingErrorAction.REPORT;
293
294 return decoder
295 .onMalformedInput(action)
296 .onUnmappableCharacter(action);
297 }
298 // </editor-fold>
299
300 // <editor-fold defaultstate="collapsed" desc="ByteBuffers">
301 /**
302 * Make a byte buffer from an input stream.
303 */
304 public ByteBuffer makeByteBuffer(InputStream in)
305 throws IOException {
306 int limit = in.available();
307 if (limit < 1024) limit = 1024;
308 ByteBuffer result = byteBufferCache.get(limit);
309 int position = 0;
310 while (in.available() != 0) {
311 if (position >= limit)
312 // expand buffer
313 result = ByteBuffer.
314 allocate(limit <<= 1).
315 put((ByteBuffer)result.flip());
316 int count = in.read(result.array(),
317 position,
318 limit - position);
319 if (count < 0) break;
320 result.position(position += count);
321 }
322 return (ByteBuffer)result.flip();
323 }
324
325 public void recycleByteBuffer(ByteBuffer bb) {
326 byteBufferCache.put(bb);
327 }
328
329 /**
330 * A single-element cache of direct byte buffers.
331 */
332 private static class ByteBufferCache {
333 private ByteBuffer cached;
334 ByteBuffer get(int capacity) {
335 if (capacity < 20480) capacity = 20480;
336 ByteBuffer result =
337 (cached != null && cached.capacity() >= capacity)
338 ? (ByteBuffer)cached.clear()
339 : ByteBuffer.allocate(capacity + capacity>>1);
340 cached = null;
341 return result;
342 }
343 void put(ByteBuffer x) {
344 cached = x;
345 }
346 }
347
348 private final ByteBufferCache byteBufferCache;
349 // </editor-fold>
350
351 // <editor-fold defaultstate="collapsed" desc="Content cache">
352 public CharBuffer getCachedContent(JavaFileObject file) {
353 ContentCacheEntry e = contentCache.get(file);
354 if (e == null)
355 return null;
356
357 if (!e.isValid(file)) {
358 contentCache.remove(file);
359 return null;
360 }
361
362 return e.getValue();
363 }
364
365 public void cache(JavaFileObject file, CharBuffer cb) {
366 contentCache.put(file, new ContentCacheEntry(file, cb));
367 }
368
369 public void flushCache(JavaFileObject file) {
370 contentCache.remove(file);
371 }
372
373 protected final Map<JavaFileObject, ContentCacheEntry> contentCache
374 = new HashMap<JavaFileObject, ContentCacheEntry>();
375
376 protected static class ContentCacheEntry {
377 final long timestamp;
378 final SoftReference<CharBuffer> ref;
379
380 ContentCacheEntry(JavaFileObject file, CharBuffer cb) {
381 this.timestamp = file.getLastModified();
382 this.ref = new SoftReference<CharBuffer>(cb);
383 }
384
385 boolean isValid(JavaFileObject file) {
386 return timestamp == file.getLastModified();
387 }
388
389 CharBuffer getValue() {
390 return ref.get();
391 }
392 }
393 // </editor-fold>
394
395 public static Kind getKind(String name) {
396 if (name.endsWith(Kind.CLASS.extension))
397 return Kind.CLASS;
398 else if (name.endsWith(Kind.SOURCE.extension))
399 return Kind.SOURCE;
400 else if (name.endsWith(Kind.HTML.extension))
401 return Kind.HTML;
402 else
403 return Kind.OTHER;
404 }
405
406 protected static <T> T nullCheck(T o) {
407 o.getClass(); // null check
408 return o;
409 }
410
411 protected static <T> Collection<T> nullCheck(Collection<T> it) {
412 for (T t : it)
413 t.getClass(); // null check
414 return it;
415 }
416 }