1 /*

     2  * Copyright (c) 2009, 2014, 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.IOException;

    30 import java.io.InputStream;

    31 import java.io.OutputStreamWriter;

    32 import java.lang.ref.SoftReference;

    33 import java.lang.reflect.Constructor;

    34 import java.net.URL;

    35 import java.net.URLClassLoader;

    36 import java.nio.ByteBuffer;

    37 import java.nio.CharBuffer;

    38 import java.nio.charset.Charset;

    39 import java.nio.charset.CharsetDecoder;

    40 import java.nio.charset.CoderResult;

    41 import java.nio.charset.CodingErrorAction;

    42 import java.nio.charset.IllegalCharsetNameException;

    43 import java.nio.charset.UnsupportedCharsetException;

    44 import java.nio.file.Path;

    45 import java.util.Collection;

    46 import java.util.HashMap;

    47 import java.util.Iterator;

    48 import java.util.Map;

    49 import java.util.Objects;

    50 import java.util.Set;

    51 

    52 import javax.tools.JavaFileManager;

    53 import javax.tools.JavaFileObject;

    54 import javax.tools.JavaFileObject.Kind;

    55 

    56 import com.sun.tools.javac.code.Lint;

    57 import com.sun.tools.javac.code.Source;

    58 import com.sun.tools.javac.file.FSInfo;

    59 import com.sun.tools.javac.file.Locations;

    60 import com.sun.tools.javac.main.Option;

    61 import com.sun.tools.javac.main.OptionHelper;

    62 import com.sun.tools.javac.main.OptionHelper.GrumpyHelper;

    63 import com.sun.tools.javac.util.DefinedBy.Api;

    64 import com.sun.tools.javac.util.JCDiagnostic.SimpleDiagnosticPosition;

    65 

    66 /**

    67  * Utility methods for building a filemanager.

    68  * There are no references here to file-system specific objects such as

    69  * java.io.File or java.nio.file.Path.

    70  */

    71 public abstract class BaseFileManager implements JavaFileManager {

    72     protected BaseFileManager(Charset charset) {

    73         this.charset = charset;

    74         byteBufferCache = new ByteBufferCache();

    75         locations = createLocations();

    76     }

    77 

    78     /**

    79      * Set the context for JavacPathFileManager.

    80      * @param context the context containing items to be associated with the file manager

    81      */

    82     public void setContext(Context context) {

    83         log = Log.instance(context);

    84         options = Options.instance(context);

    85         classLoaderClass = options.get("procloader");

    86         locations.update(log, Lint.instance(context), FSInfo.instance(context));

    87     }

    88 

    89     protected Locations createLocations() {

    90         return new Locations();

    91     }

    92 

    93     /**

    94      * The log to be used for error reporting.

    95      */

    96     public Log log;

    97 

    98     /**

    99      * User provided charset (through javax.tools).

   100      */

   101     protected Charset charset;

   102 

   103     protected Options options;

   104 

   105     protected String classLoaderClass;

   106 

   107     protected Locations locations;

   108 

   109     /**

   110      * A flag for clients to use to indicate that this file manager should

   111      * be closed when it is no longer required.

   112      */

   113     public boolean autoClose;

   114 

   115     protected Source getSource() {

   116         String sourceName = options.get(Option.SOURCE);

   117         Source source = null;

   118         if (sourceName != null)

   119             source = Source.lookup(sourceName);

   120         return (source != null ? source : Source.DEFAULT);

   121     }

   122 

   123     protected ClassLoader getClassLoader(URL[] urls) {

   124         ClassLoader thisClassLoader = getClass().getClassLoader();

   125 

   126         // Allow the following to specify a closeable classloader

   127         // other than URLClassLoader.

   128 

   129         // 1: Allow client to specify the class to use via hidden option

   130         if (classLoaderClass != null) {

   131             try {

   132                 Class<? extends ClassLoader> loader =

   133                         Class.forName(classLoaderClass).asSubclass(ClassLoader.class);

   134                 Class<?>[] constrArgTypes = { URL[].class, ClassLoader.class };

   135                 Constructor<? extends ClassLoader> constr = loader.getConstructor(constrArgTypes);

   136                 return constr.newInstance(urls, thisClassLoader);

   137             } catch (ReflectiveOperationException t) {

   138                 // ignore errors loading user-provided class loader, fall through

   139             }

   140         }

   141         return new URLClassLoader(urls, thisClassLoader);

   142     }

   143 

   144     public boolean isDefaultBootClassPath() {

   145         return locations.isDefaultBootClassPath();

   146     }

   147 

   148     // <editor-fold defaultstate="collapsed" desc="Option handling">

   149     @Override @DefinedBy(Api.COMPILER)

   150     public boolean handleOption(String current, Iterator<String> remaining) {

   151         OptionHelper helper = new GrumpyHelper(log) {

   152             @Override

   153             public String get(Option option) {

   154                 return options.get(option.getText());

   155             }

   156 

   157             @Override

   158             public void put(String name, String value) {

   159                 options.put(name, value);

   160             }

   161 

   162             @Override

   163             public void remove(String name) {

   164                 options.remove(name);

   165             }

   166 

   167             @Override

   168             public boolean handleFileManagerOption(Option option, String value) {

   169                 return handleOption(option, value);

   170             }

   171         };

   172 

   173         for (Option o: javacFileManagerOptions) {

   174             if (o.matches(current))  {

   175                 if (o.hasArg()) {

   176                     if (remaining.hasNext()) {

   177                         if (!o.process(helper, current, remaining.next()))

   178                             return true;

   179                     }

   180                 } else {

   181                     if (!o.process(helper, current))

   182                         return true;

   183                 }

   184                 // operand missing, or process returned true

   185                 throw new IllegalArgumentException(current);

   186             }

   187         }

   188 

   189         return false;

   190     }

   191     // where

   192         private static final Set<Option> javacFileManagerOptions =

   193             Option.getJavacFileManagerOptions();

   194 

   195     @Override @DefinedBy(Api.COMPILER)

   196     public int isSupportedOption(String option) {

   197         for (Option o : javacFileManagerOptions) {

   198             if (o.matches(option))

   199                 return o.hasArg() ? 1 : 0;

   200         }

   201         return -1;

   202     }

   203 

   204     /**

   205      * Common back end for OptionHelper handleFileManagerOption.

   206      * @param option the option whose value to be set

   207      * @param value the value for the option

   208      * @return true if successful, and false otherwise

   209      */

   210     public boolean handleOption(Option option, String value) {

   211         return locations.handleOption(option, value);

   212     }

   213 

   214     /**

   215      * Call handleOption for collection of options and corresponding values.

   216      * @param map a collection of options and corresponding values

   217      * @return true if all the calls are successful

   218      */

   219     public boolean handleOptions(Map<Option, String> map) {

   220         boolean ok = true;

   221         for (Map.Entry<Option, String> e: map.entrySet())

   222             ok = ok & handleOption(e.getKey(), e.getValue());

   223         return ok;

   224     }

   225 

   226     // </editor-fold>

   227 

   228     // <editor-fold defaultstate="collapsed" desc="Encoding">

   229     private String defaultEncodingName;

   230     private String getDefaultEncodingName() {

   231         if (defaultEncodingName == null) {

   232             defaultEncodingName =

   233                 new OutputStreamWriter(new ByteArrayOutputStream()).getEncoding();

   234         }

   235         return defaultEncodingName;

   236     }

   237 

   238     public String getEncodingName() {

   239         String encName = options.get(Option.ENCODING);

   240         if (encName == null)

   241             return getDefaultEncodingName();

   242         else

   243             return encName;

   244     }

   245 

   246     @SuppressWarnings("cast")

   247     public CharBuffer decode(ByteBuffer inbuf, boolean ignoreEncodingErrors) {

   248         String encodingName = getEncodingName();

   249         CharsetDecoder decoder;

   250         try {

   251             decoder = getDecoder(encodingName, ignoreEncodingErrors);

   252         } catch (IllegalCharsetNameException | UnsupportedCharsetException e) {

   253             log.error("unsupported.encoding", encodingName);

   254             return (CharBuffer)CharBuffer.allocate(1).flip();

   255         }

   256 

   257         // slightly overestimate the buffer size to avoid reallocation.

   258         float factor =

   259             decoder.averageCharsPerByte() * 0.8f +

   260             decoder.maxCharsPerByte() * 0.2f;

   261         CharBuffer dest = CharBuffer.

   262             allocate(10 + (int)(inbuf.remaining()*factor));

   263 

   264         while (true) {

   265             CoderResult result = decoder.decode(inbuf, dest, true);

   266             dest.flip();

   267 

   268             if (result.isUnderflow()) { // done reading

   269                 // make sure there is at least one extra character

   270                 if (dest.limit() == dest.capacity()) {

   271                     dest = CharBuffer.allocate(dest.capacity()+1).put(dest);

   272                     dest.flip();

   273                 }

   274                 return dest;

   275             } else if (result.isOverflow()) { // buffer too small; expand

   276                 int newCapacity =

   277                     10 + dest.capacity() +

   278                     (int)(inbuf.remaining()*decoder.maxCharsPerByte());

   279                 dest = CharBuffer.allocate(newCapacity).put(dest);

   280             } else if (result.isMalformed() || result.isUnmappable()) {

   281                 // bad character in input

   282 

   283                 log.error(new SimpleDiagnosticPosition(dest.limit()),

   284                           "illegal.char.for.encoding",

   285                           charset == null ? encodingName : charset.name());

   286 

   287                 // skip past the coding error

   288                 inbuf.position(inbuf.position() + result.length());

   289 

   290                 // undo the flip() to prepare the output buffer

   291                 // for more translation

   292                 dest.position(dest.limit());

   293                 dest.limit(dest.capacity());

   294                 dest.put((char)0xfffd); // backward compatible

   295             } else {

   296                 throw new AssertionError(result);

   297             }

   298         }

   299         // unreached

   300     }

   301 

   302     public CharsetDecoder getDecoder(String encodingName, boolean ignoreEncodingErrors) {

   303         Charset cs = (this.charset == null)

   304             ? Charset.forName(encodingName)

   305             : this.charset;

   306         CharsetDecoder decoder = cs.newDecoder();

   307 

   308         CodingErrorAction action;

   309         if (ignoreEncodingErrors)

   310             action = CodingErrorAction.REPLACE;

   311         else

   312             action = CodingErrorAction.REPORT;

   313 

   314         return decoder

   315             .onMalformedInput(action)

   316             .onUnmappableCharacter(action);

   317     }

   318     // </editor-fold>

   319 

   320     // <editor-fold defaultstate="collapsed" desc="ByteBuffers">

   321     /**

   322      * Make a byte buffer from an input stream.

   323      * @param in the stream

   324      * @return a byte buffer containing the contents of the stream

   325      * @throws IOException if an error occurred while reading the stream

   326      */

   327     @SuppressWarnings("cast")

   328     public ByteBuffer makeByteBuffer(InputStream in)

   329         throws IOException {

   330         int limit = in.available();

   331         if (limit < 1024) limit = 1024;

   332         ByteBuffer result = byteBufferCache.get(limit);

   333         int position = 0;

   334         while (in.available() != 0) {

   335             if (position >= limit)

   336                 // expand buffer

   337                 result = ByteBuffer.

   338                     allocate(limit <<= 1).

   339                     put((ByteBuffer)result.flip());

   340             int count = in.read(result.array(),

   341                 position,

   342                 limit - position);

   343             if (count < 0) break;

   344             result.position(position += count);

   345         }

   346         return (ByteBuffer)result.flip();

   347     }

   348 

   349     public void recycleByteBuffer(ByteBuffer bb) {

   350         byteBufferCache.put(bb);

   351     }

   352 

   353     /**

   354      * A single-element cache of direct byte buffers.

   355      */

   356     @SuppressWarnings("cast")

   357     private static class ByteBufferCache {

   358         private ByteBuffer cached;

   359         ByteBuffer get(int capacity) {

   360             if (capacity < 20480) capacity = 20480;

   361             ByteBuffer result =

   362                 (cached != null && cached.capacity() >= capacity)

   363                 ? (ByteBuffer)cached.clear()

   364                 : ByteBuffer.allocate(capacity + capacity>>1);

   365             cached = null;

   366             return result;

   367         }

   368         void put(ByteBuffer x) {

   369             cached = x;

   370         }

   371     }

   372 

   373     private final ByteBufferCache byteBufferCache;

   374     // </editor-fold>

   375 

   376     // <editor-fold defaultstate="collapsed" desc="Content cache">

   377     public CharBuffer getCachedContent(JavaFileObject file) {

   378         ContentCacheEntry e = contentCache.get(file);

   379         if (e == null)

   380             return null;

   381 

   382         if (!e.isValid(file)) {

   383             contentCache.remove(file);

   384             return null;

   385         }

   386 

   387         return e.getValue();

   388     }

   389 

   390     public void cache(JavaFileObject file, CharBuffer cb) {

   391         contentCache.put(file, new ContentCacheEntry(file, cb));

   392     }

   393 

   394     public void flushCache(JavaFileObject file) {

   395         contentCache.remove(file);

   396     }

   397 

   398     protected final Map<JavaFileObject, ContentCacheEntry> contentCache = new HashMap<>();

   399 

   400     protected static class ContentCacheEntry {

   401         final long timestamp;

   402         final SoftReference<CharBuffer> ref;

   403 

   404         ContentCacheEntry(JavaFileObject file, CharBuffer cb) {

   405             this.timestamp = file.getLastModified();

   406             this.ref = new SoftReference<>(cb);

   407         }

   408 

   409         boolean isValid(JavaFileObject file) {

   410             return timestamp == file.getLastModified();

   411         }

   412 

   413         CharBuffer getValue() {

   414             return ref.get();

   415         }

   416     }

   417     // </editor-fold>

   418 

   419     public static Kind getKind(Path path) {

   420         return getKind(path.getFileName().toString());

   421     }

   422 

   423     public static Kind getKind(String name) {

   424         if (name.endsWith(Kind.CLASS.extension))

   425             return Kind.CLASS;

   426         else if (name.endsWith(Kind.SOURCE.extension))

   427             return Kind.SOURCE;

   428         else if (name.endsWith(Kind.HTML.extension))

   429             return Kind.HTML;

   430         else

   431             return Kind.OTHER;

   432     }

   433 

   434     protected static <T> T nullCheck(T o) {

   435         return Objects.requireNonNull(o);

   436     }

   437 

   438     protected static <T> Collection<T> nullCheck(Collection<T> it) {

   439         for (T t : it)

   440             Objects.requireNonNull(t);

   441         return it;

   442     }

   443 }