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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package com.sun.tools.javac.file;

import java.io.IOException;
import java.io.InputStream;
import java.lang.ref.SoftReference;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.URL;
import java.net.URLClassLoader;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;
import java.nio.charset.CoderResult;
import java.nio.charset.CodingErrorAction;
import java.nio.charset.IllegalCharsetNameException;
import java.nio.charset.UnsupportedCharsetException;
import java.nio.file.Path;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Objects;
import java.util.Set;

import javax.tools.JavaFileManager;
import javax.tools.JavaFileObject;
import javax.tools.JavaFileObject.Kind;

import com.sun.tools.javac.main.Option;
import com.sun.tools.javac.main.OptionHelper;
import com.sun.tools.javac.main.OptionHelper.GrumpyHelper;
import com.sun.tools.javac.resources.CompilerProperties.Errors;
import com.sun.tools.javac.util.Abort;
import com.sun.tools.javac.util.Context;
import com.sun.tools.javac.util.DefinedBy;
import com.sun.tools.javac.util.DefinedBy.Api;
import com.sun.tools.javac.util.Log;
import com.sun.tools.javac.util.Options;

Utility methods for building a filemanager. There are no references here to file-system specific objects such as java.io.File or java.nio.file.Path.
/** * Utility methods for building a filemanager. * There are no references here to file-system specific objects such as * java.io.File or java.nio.file.Path. */
public abstract class BaseFileManager implements JavaFileManager { protected BaseFileManager(Charset charset) { this.charset = charset; byteBufferCache = new ByteBufferCache(); locations = createLocations(); }
Set the context for JavacPathFileManager.
Params:
  • context – the context containing items to be associated with the file manager
/** * Set the context for JavacPathFileManager. * @param context the context containing items to be associated with the file manager */
public void setContext(Context context) { log = Log.instance(context); options = Options.instance(context); classLoaderClass = options.get("procloader"); // Avoid initializing Lint boolean warn = options.isLintSet("path"); locations.update(log, warn, FSInfo.instance(context)); // Setting this option is an indication that close() should defer actually closing // the file manager until after a specified period of inactivity. // This is to accomodate clients which save references to Symbols created for use // within doclets or annotation processors, and which then attempt to use those // references after the tool exits, having closed any internally managed file manager. // Ideally, such clients should run the tool via the javax.tools API, providing their // own file manager, which can be closed by the client when all use of that file // manager is complete. // If the option has a numeric value, it will be interpreted as the duration, // in seconds, of the period of inactivity to wait for, before the file manager // is actually closed. // See also deferredClose(). String s = options.get("fileManager.deferClose"); if (s != null) { try { deferredCloseTimeout = (int) (Float.parseFloat(s) * 1000); } catch (NumberFormatException e) { deferredCloseTimeout = 60 * 1000; // default: one minute, in millis } } } protected Locations createLocations() { return new Locations(); }
The log to be used for error reporting.
/** * The log to be used for error reporting. */
public Log log;
User provided charset (through javax.tools).
/** * User provided charset (through javax.tools). */
protected Charset charset; protected Options options; protected String classLoaderClass; protected final Locations locations;
A flag for clients to use to indicate that this file manager should be closed when it is no longer required.
/** * A flag for clients to use to indicate that this file manager should * be closed when it is no longer required. */
public boolean autoClose;
Wait for a period of inactivity before calling close(). The length of the period of inactivity is given by deferredCloseTimeout
/** * Wait for a period of inactivity before calling close(). * The length of the period of inactivity is given by {@code deferredCloseTimeout} */
protected void deferredClose() { Thread t = new Thread(getClass().getName() + " DeferredClose") { @Override public void run() { try { synchronized (BaseFileManager.this) { long now = System.currentTimeMillis(); while (now < lastUsedTime + deferredCloseTimeout) { BaseFileManager.this.wait(lastUsedTime + deferredCloseTimeout - now); now = System.currentTimeMillis(); } deferredCloseTimeout = 0; close(); } } catch (InterruptedException e) { } catch (IOException e) { } } }; t.setDaemon(true); t.start(); } synchronized void updateLastUsedTime() { if (deferredCloseTimeout > 0) { // avoid updating the time unnecessarily lastUsedTime = System.currentTimeMillis(); } } private long lastUsedTime = System.currentTimeMillis(); protected long deferredCloseTimeout = 0; protected ClassLoader getClassLoader(URL[] urls) { ClassLoader thisClassLoader = getClass().getClassLoader(); // Allow the following to specify a closeable classloader // other than URLClassLoader. // 1: Allow client to specify the class to use via hidden option if (classLoaderClass != null) { try { Class<? extends ClassLoader> loader = Class.forName(classLoaderClass).asSubclass(ClassLoader.class); Class<?>[] constrArgTypes = { URL[].class, ClassLoader.class }; Constructor<? extends ClassLoader> constr = loader.getConstructor(constrArgTypes); return constr.newInstance(urls, thisClassLoader); } catch (ReflectiveOperationException t) { // ignore errors loading user-provided class loader, fall through } } return new URLClassLoader(urls, thisClassLoader); } public boolean isDefaultBootClassPath() { return locations.isDefaultBootClassPath(); } // <editor-fold defaultstate="collapsed" desc="Option handling"> @Override @DefinedBy(Api.COMPILER) public boolean handleOption(String current, Iterator<String> remaining) { OptionHelper helper = new GrumpyHelper(log) { @Override public String get(Option option) { return options.get(option); } @Override public void put(String name, String value) { options.put(name, value); } @Override public void remove(String name) { options.remove(name); } @Override public boolean handleFileManagerOption(Option option, String value) { return handleOption(option, value); } }; Option o = Option.lookup(current, javacFileManagerOptions); if (o == null) { return false; } try { o.handleOption(helper, current, remaining); } catch (Option.InvalidValueException e) { throw new IllegalArgumentException(e.getMessage(), e); } return true; } // where private static final Set<Option> javacFileManagerOptions = Option.getJavacFileManagerOptions(); @Override @DefinedBy(Api.COMPILER) public int isSupportedOption(String option) { Option o = Option.lookup(option, javacFileManagerOptions); return (o == null) ? -1 : o.hasArg() ? 1 : 0; } protected String multiReleaseValue;
Common back end for OptionHelper handleFileManagerOption.
Params:
  • option – the option whose value to be set
  • value – the value for the option
Returns:true if successful, and false otherwise
/** * Common back end for OptionHelper handleFileManagerOption. * @param option the option whose value to be set * @param value the value for the option * @return true if successful, and false otherwise */
public boolean handleOption(Option option, String value) { switch (option) { case ENCODING: encodingName = value; return true; case MULTIRELEASE: multiReleaseValue = value; locations.setMultiReleaseValue(value); return true; default: return locations.handleOption(option, value); } }
Call handleOption for collection of options and corresponding values.
Params:
  • map – a collection of options and corresponding values
Returns:true if all the calls are successful
/** * Call handleOption for collection of options and corresponding values. * @param map a collection of options and corresponding values * @return true if all the calls are successful */
public boolean handleOptions(Map<Option, String> map) { boolean ok = true; for (Map.Entry<Option, String> e: map.entrySet()) { try { ok = ok & handleOption(e.getKey(), e.getValue()); } catch (IllegalArgumentException ex) { log.error(Errors.IllegalArgumentForOption(e.getKey().getPrimaryName(), ex.getMessage())); ok = false; } } return ok; } // </editor-fold> // <editor-fold defaultstate="collapsed" desc="Encoding"> private String encodingName; private String defaultEncodingName; private String getDefaultEncodingName() { if (defaultEncodingName == null) { defaultEncodingName = Charset.defaultCharset().name(); } return defaultEncodingName; } public String getEncodingName() { return (encodingName != null) ? encodingName : getDefaultEncodingName(); } @SuppressWarnings("cast") public CharBuffer decode(ByteBuffer inbuf, boolean ignoreEncodingErrors) { String encName = getEncodingName(); CharsetDecoder decoder; try { decoder = getDecoder(encName, ignoreEncodingErrors); } catch (IllegalCharsetNameException | UnsupportedCharsetException e) { log.error("unsupported.encoding", encName); return (CharBuffer)CharBuffer.allocate(1).flip(); } // slightly overestimate the buffer size to avoid reallocation. float factor = decoder.averageCharsPerByte() * 0.8f + decoder.maxCharsPerByte() * 0.2f; CharBuffer dest = CharBuffer. allocate(10 + (int)(inbuf.remaining()*factor)); while (true) { CoderResult result = decoder.decode(inbuf, dest, true); dest.flip(); if (result.isUnderflow()) { // done reading // make sure there is at least one extra character if (dest.limit() == dest.capacity()) { dest = CharBuffer.allocate(dest.capacity()+1).put(dest); dest.flip(); } return dest; } else if (result.isOverflow()) { // buffer too small; expand int newCapacity = 10 + dest.capacity() + (int)(inbuf.remaining()*decoder.maxCharsPerByte()); dest = CharBuffer.allocate(newCapacity).put(dest); } else if (result.isMalformed() || result.isUnmappable()) { // bad character in input StringBuilder unmappable = new StringBuilder(); int len = result.length(); for (int i = 0; i < len; i++) { unmappable.append(String.format("%02X", inbuf.get())); } String charsetName = charset == null ? encName : charset.name(); log.error(dest.limit(), Errors.IllegalCharForEncoding(unmappable.toString(), charsetName)); // undo the flip() to prepare the output buffer // for more translation dest.position(dest.limit()); dest.limit(dest.capacity()); dest.put((char)0xfffd); // backward compatible } else { throw new AssertionError(result); } } // unreached } public CharsetDecoder getDecoder(String encodingName, boolean ignoreEncodingErrors) { Charset cs = (this.charset == null) ? Charset.forName(encodingName) : this.charset; CharsetDecoder decoder = cs.newDecoder(); CodingErrorAction action; if (ignoreEncodingErrors) action = CodingErrorAction.REPLACE; else action = CodingErrorAction.REPORT; return decoder .onMalformedInput(action) .onUnmappableCharacter(action); } // </editor-fold> // <editor-fold defaultstate="collapsed" desc="ByteBuffers">
Make a byte buffer from an input stream.
Params:
  • in – the stream
Throws:
  • IOException – if an error occurred while reading the stream
Returns:a byte buffer containing the contents of the stream
/** * Make a byte buffer from an input stream. * @param in the stream * @return a byte buffer containing the contents of the stream * @throws IOException if an error occurred while reading the stream */
@SuppressWarnings("cast") public ByteBuffer makeByteBuffer(InputStream in) throws IOException { int limit = in.available(); if (limit < 1024) limit = 1024; ByteBuffer result = byteBufferCache.get(limit); int position = 0; while (in.available() != 0) { if (position >= limit) // expand buffer result = ByteBuffer. allocate(limit <<= 1). put((ByteBuffer)result.flip()); int count = in.read(result.array(), position, limit - position); if (count < 0) break; result.position(position += count); } return (ByteBuffer)result.flip(); } public void recycleByteBuffer(ByteBuffer bb) { byteBufferCache.put(bb); }
A single-element cache of direct byte buffers.
/** * A single-element cache of direct byte buffers. */
@SuppressWarnings("cast") private static class ByteBufferCache { private ByteBuffer cached; ByteBuffer get(int capacity) { if (capacity < 20480) capacity = 20480; ByteBuffer result = (cached != null && cached.capacity() >= capacity) ? (ByteBuffer)cached.clear() : ByteBuffer.allocate(capacity + capacity>>1); cached = null; return result; } void put(ByteBuffer x) { cached = x; } } private final ByteBufferCache byteBufferCache; // </editor-fold> // <editor-fold defaultstate="collapsed" desc="Content cache"> public CharBuffer getCachedContent(JavaFileObject file) { ContentCacheEntry e = contentCache.get(file); if (e == null) return null; if (!e.isValid(file)) { contentCache.remove(file); return null; } return e.getValue(); } public void cache(JavaFileObject file, CharBuffer cb) { contentCache.put(file, new ContentCacheEntry(file, cb)); } public void flushCache(JavaFileObject file) { contentCache.remove(file); } protected final Map<JavaFileObject, ContentCacheEntry> contentCache = new HashMap<>(); protected static class ContentCacheEntry { final long timestamp; final SoftReference<CharBuffer> ref; ContentCacheEntry(JavaFileObject file, CharBuffer cb) { this.timestamp = file.getLastModified(); this.ref = new SoftReference<>(cb); } boolean isValid(JavaFileObject file) { return timestamp == file.getLastModified(); } CharBuffer getValue() { return ref.get(); } } // </editor-fold> public static Kind getKind(Path path) { return getKind(path.getFileName().toString()); } public static Kind getKind(String name) { if (name.endsWith(Kind.CLASS.extension)) return Kind.CLASS; else if (name.endsWith(Kind.SOURCE.extension)) return Kind.SOURCE; else if (name.endsWith(Kind.HTML.extension)) return Kind.HTML; else return Kind.OTHER; } protected static <T> T nullCheck(T o) { return Objects.requireNonNull(o); } protected static <T> Collection<T> nullCheck(Collection<T> it) { for (T t : it) Objects.requireNonNull(t); return it; } }