JDK14/Java14源码在线阅读
/*
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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.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package jdk.jshell;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URI;
import java.nio.file.FileSystems;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.TreeMap;
import javax.tools.JavaFileObject.Kind;
import static javax.tools.StandardLocation.CLASS_PATH;
import javax.tools.FileObject;
import javax.tools.JavaFileManager;
import javax.tools.JavaFileObject;
import javax.tools.SimpleJavaFileObject;
import javax.tools.StandardJavaFileManager;
import javax.tools.StandardLocation;
import static jdk.internal.jshell.debug.InternalDebugControl.DBG_FMGR;
/**
* File manager for the compiler API. Reads from memory (Strings) and writes
* class files to memory (cached OutputMemoryJavaFileObject).
*
* @author Robert Field
*/
class MemoryFileManager implements JavaFileManager {
private final StandardJavaFileManager stdFileManager;
private final Map<String, OutputMemoryJavaFileObject> classObjects = new TreeMap<>();
private ClassFileCreationListener classListener = null;
private final JShell proc;
Iterable<? extends Path> getLocationAsPaths(Location loc) {
return this.stdFileManager.getLocationAsPaths(loc);
}
static abstract class MemoryJavaFileObject extends SimpleJavaFileObject {
public MemoryJavaFileObject(String name, JavaFileObject.Kind kind) {
super(URI.create("string:///" + name.replace('.', '/')
+ kind.extension), kind);
}
}
class SourceMemoryJavaFileObject extends MemoryJavaFileObject {
private final String src;
private final Object origin;
SourceMemoryJavaFileObject(Object origin, String className, String code) {
super(className, JavaFileObject.Kind.SOURCE);
this.origin = origin;
this.src = code;
}
public Object getOrigin() {
return origin;
}
@Override
public CharSequence getCharContent(boolean ignoreEncodingErrors) {
return src;
}
}
static class OutputMemoryJavaFileObject extends MemoryJavaFileObject {
/**
* Byte code created by the compiler will be stored in this
* ByteArrayOutputStream.
*/
private ByteArrayOutputStream bos = new ByteArrayOutputStream();
private byte[] bytes = null;
private final String className;
public OutputMemoryJavaFileObject(String name, JavaFileObject.Kind kind) {
super(name, kind);
this.className = name;
}
public byte[] getBytes() {
if (bytes == null) {
bytes = bos.toByteArray();
bos = null;
}
return bytes;
}
public void dump() {
try {
Path dumpDir = FileSystems.getDefault().getPath("dump");
if (Files.notExists(dumpDir)) {
Files.createDirectory(dumpDir);
}
Path file = FileSystems.getDefault().getPath("dump", getName() + ".class");
Files.write(file, getBytes());
} catch (IOException ex) {
throw new RuntimeException(ex);
}
}
@Override
public String getName() {
return className;
}
/**
* Will provide the compiler with an output stream that leads to our
* byte array.
*/
@Override
public OutputStream openOutputStream() throws IOException {
return bos;
}
@Override
public InputStream openInputStream() throws IOException {
return new ByteArrayInputStream(getBytes());
}
}
public MemoryFileManager(StandardJavaFileManager standardManager, JShell proc) {
this.stdFileManager = proc.fileManagerMapping != null
? proc.fileManagerMapping.apply(standardManager)
: standardManager;
this.proc = proc;
}
private Collection<OutputMemoryJavaFileObject> generatedClasses() {
return classObjects.values();
}
// For debugging dumps
public void dumpClasses() {
for (OutputMemoryJavaFileObject co : generatedClasses()) {
co.dump();
}
}
public JavaFileObject createSourceFileObject(Object origin, String name, String code) {
return new SourceMemoryJavaFileObject(origin, name, code);
}
/**
* Returns a class loader for loading plug-ins from the given location. For
* example, to load annotation processors, a compiler will request a class
* loader for the {@link
* StandardLocation#ANNOTATION_PROCESSOR_PATH
* ANNOTATION_PROCESSOR_PATH} location.
*
* @param location a location
* @return a class loader for the given location; or {@code null}
* if loading plug-ins from the given location is disabled or if
* the location is not known
* @throws SecurityException if a class loader can not be created
* in the current security context
* @throws IllegalStateException if {@link #close} has been called
* and this file manager cannot be reopened
*/
@Override
public ClassLoader getClassLoader(JavaFileManager.Location location) {
proc.debug(DBG_FMGR, "getClassLoader: location\n", location);
return stdFileManager.getClassLoader(location);
}
/**
* Lists all file objects matching the given criteria in the given
* location. List file objects in "subpackages" if recurse is
* true.
*
* <p>Note: even if the given location is unknown to this file
* manager, it may not return {@code null}. Also, an unknown
* location may not cause an exception.
*
* @param location a location
* @param packageName a package name
* @param kinds return objects only of these kinds
* @param recurse if true include "subpackages"
* @return an Iterable of file objects matching the given criteria
* @throws IOException if an I/O error occurred, or if {@link
* #close} has been called and this file manager cannot be
* reopened
* @throws IllegalStateException if {@link #close} has been called
* and this file manager cannot be reopened
*/
@Override
public Iterable<JavaFileObject> list(JavaFileManager.Location location,
String packageName,
Set<JavaFileObject.Kind> kinds,
boolean recurse)
throws IOException {
Iterable<JavaFileObject> stdList = stdFileManager.list(location, packageName, kinds, recurse);
if (location==CLASS_PATH && packageName.equals("REPL")) {
// if the desired list is for our JShell package, lazily iterate over
// first the standard list then any generated classes.
return () -> new Iterator<JavaFileObject>() {
boolean stdDone = false;
Iterator<? extends JavaFileObject> it;
@Override
public boolean hasNext() {
if (it == null) {
it = stdList.iterator();
}
if (it.hasNext()) {
return true;
}
if (stdDone) {
return false;
} else {
stdDone = true;
it = generatedClasses().iterator();
return it.hasNext();
}
}
@Override
public JavaFileObject next() {
if (!hasNext()) {
throw new NoSuchElementException();
}
return it.next();
}
};
} else {
return stdList;
}
}
/**
* Infers a binary name of a file object based on a location. The
* binary name returned might not be a valid binary name according to
* <cite>The Java&trade { throw new UnsupportedOperationException("Not supported yet."); } Language Specification</cite>.
*
* @param location a location
* @param file a file object
* @return a binary name or {@code null} the file object is not
* found in the given location
* @throws IllegalStateException if {@link #close} has been called
* and this file manager cannot be reopened
*/
@Override
public String inferBinaryName(JavaFileManager.Location location, JavaFileObject file) {
if (file instanceof OutputMemoryJavaFileObject) {
OutputMemoryJavaFileObject ofo = (OutputMemoryJavaFileObject) file;
proc.debug(DBG_FMGR, "inferBinaryName %s => %s\n", file, ofo.getName());
return ofo.getName();
} else {
return stdFileManager.inferBinaryName(location, file);
}
}
/**
* Compares two file objects and return true if they represent the
* same underlying object.
*
* @param a a file object
* @param b a file object
* @return true if the given file objects represent the same
* underlying object
*
* @throws IllegalArgumentException if either of the arguments
* were created with another file manager and this file manager
* does not support foreign file objects
*/
@Override
public boolean isSameFile(FileObject a, FileObject b) {
return stdFileManager.isSameFile(b, b);
}
/**
* Determines if the given option is supported and if so, the
* number of arguments the option takes.
*
* @param option an option
* @return the number of arguments the given option takes or -1 if
* the option is not supported
*/
@Override
public int isSupportedOption(String option) {
proc.debug(DBG_FMGR, "isSupportedOption: %s\n", option);
return stdFileManager.isSupportedOption(option);
}
/**
* Handles one option. If {@code current} is an option to this
* file manager it will consume any arguments to that option from
* {@code remaining} and return true, otherwise return false.
*
* @param current current option
* @param remaining remaining options
* @return true if this option was handled by this file manager,
* false otherwise
* @throws IllegalArgumentException if this option to this file
* manager is used incorrectly
* @throws IllegalStateException if {@link #close} has been called
* and this file manager cannot be reopened
*/
@Override
public boolean handleOption(String current, Iterator<String> remaining) {
proc.debug(DBG_FMGR, "handleOption: current: %s\n", current +
", remaining: " + remaining);
return stdFileManager.handleOption(current, remaining);
}
/**
* Determines if a location is known to this file manager.
*
* @param location a location
* @return true if the location is known
*/
@Override
public boolean hasLocation(JavaFileManager.Location location) {
proc.debug(DBG_FMGR, "hasLocation: location: %s\n", location);
return stdFileManager.hasLocation(location);
}
interface ClassFileCreationListener {
void newClassFile(OutputMemoryJavaFileObject jfo, JavaFileManager.Location location,
String className, Kind kind, FileObject sibling);
}
void registerClassFileCreationListener(ClassFileCreationListener listen) {
this.classListener = listen;
}
/**
* Returns a {@linkplain JavaFileObject file object} for input
* representing the specified class of the specified kind in the
* given location.
*
* @param location a location
* @param className the name of a class
* @param kind the kind of file, must be one of {@link
* JavaFileObject.Kind#SOURCE SOURCE} or {@link
* JavaFileObject.Kind#CLASS CLASS}
* @return a file object, might return {@code null} if the
* file does not exist
* @throws IllegalArgumentException if the location is not known
* to this file manager and the file manager does not support
* unknown locations, or if the kind is not valid
* @throws IOException if an I/O error occurred, or if {@link
* #close} has been called and this file manager cannot be
* reopened
* @throws IllegalStateException if {@link #close} has been called
* and this file manager cannot be reopened
*/
@Override
public JavaFileObject getJavaFileForInput(JavaFileManager.Location location,
String className,
JavaFileObject.Kind kind)
throws IOException {
return stdFileManager.getJavaFileForInput(location, className, kind);
}
/**
* Returns a {@linkplain JavaFileObject file object} for output
* representing the specified class of the specified kind in the
* given location.
*
* <p>Optionally, this file manager might consider the sibling as
* a hint for where to place the output. The exact semantics of
* this hint is unspecified. The JDK compiler, javac, for
* example, will place class files in the same directories as
* originating source files unless a class file output directory
* is provided. To facilitate this behavior, javac might provide
* the originating source file as sibling when calling this
* method.
*
* @param location a location
* @param className the name of a class
* @param kind the kind of file, must be one of {@link
* JavaFileObject.Kind#SOURCE SOURCE} or {@link
* JavaFileObject.Kind#CLASS CLASS}
* @param sibling a file object to be used as hint for placement;
* might be {@code null}
* @return a file object for output
* @throws IllegalArgumentException if sibling is not known to
* this file manager, or if the location is not known to this file
* manager and the file manager does not support unknown
* locations, or if the kind is not valid
* @throws IOException if an I/O error occurred, or if {@link
* #close} has been called and this file manager cannot be
* reopened
* @throws IllegalStateException {@link #close} has been called
* and this file manager cannot be reopened
*/
@Override
public JavaFileObject getJavaFileForOutput(JavaFileManager.Location location,
String className, Kind kind, FileObject sibling) throws IOException {
OutputMemoryJavaFileObject fo;
fo = new OutputMemoryJavaFileObject(className, kind);
classObjects.put(className, fo);
proc.debug(DBG_FMGR, "Set out file: %s = %s\n", className, fo);
if (classListener != null) {
classListener.newClassFile(fo, location, className, kind, sibling);
}
return fo;
}
/**
* Returns a {@linkplain FileObject file object} for input
* representing the specified <a href="JavaFileManager.html#relative_name">relative
* name</a> in the specified package in the given location.
*
* <p>If the returned object represents a {@linkplain
* JavaFileObject.Kind#SOURCE source} or {@linkplain
* JavaFileObject.Kind#CLASS class} file, it must be an instance
* of {@link JavaFileObject}.
*
* <p>Informally, the file object returned by this method is
* located in the concatenation of the location, package name, and
* relative name. For example, to locate the properties file
* "resources/compiler.properties" in the package
* "com.sun.tools.javac" in the {@linkplain
* StandardLocation#SOURCE_PATH SOURCE_PATH} location, this method
* might be called like so:
*
* <pre>getFileForInput(SOURCE_PATH, "com.sun.tools.javac", "resources/compiler.properties");</pre>
*
* <p>If the call was executed on Windows, with SOURCE_PATH set to
* <code>"C:\Documents and Settings\UncleBob\src\share\classes"</code>,
* a valid result would be a file object representing the file
* <code>"C:\Documents and Settings\UncleBob\src\share\classes\com\sun\tools\javac\resources\compiler.properties"</code>.
*
* @param location a location
* @param packageName a package name
* @param relativeName a relative name
* @return a file object, might return {@code null} if the file
* does not exist
* @throws IllegalArgumentException if the location is not known
* to this file manager and the file manager does not support
* unknown locations, or if {@code relativeName} is not valid
* @throws IOException if an I/O error occurred, or if {@link
* #close} has been called and this file manager cannot be
* reopened
* @throws IllegalStateException if {@link #close} has been called
* and this file manager cannot be reopened
*/
@Override
public FileObject getFileForInput(JavaFileManager.Location location,
String packageName,
String relativeName)
throws IOException {
proc.debug(DBG_FMGR, "getFileForInput location=%s packageName=%s\n", location, packageName);
return stdFileManager.getFileForInput(location, packageName, relativeName);
}
/**
* Returns a {@linkplain FileObject file object} for output
* representing the specified <a href="JavaFileManager.html#relative_name">relative
* name</a> in the specified package in the given location.
*
* <p>Optionally, this file manager might consider the sibling as
* a hint for where to place the output. The exact semantics of
* this hint is unspecified. The JDK compiler, javac, for
* example, will place class files in the same directories as
* originating source files unless a class file output directory
* is provided. To facilitate this behavior, javac might provide
* the originating source file as sibling when calling this
* method.
*
* <p>If the returned object represents a {@linkplain
* JavaFileObject.Kind#SOURCE source} or {@linkplain
* JavaFileObject.Kind#CLASS class} file, it must be an instance
* of {@link JavaFileObject}.
*
* <p>Informally, the file object returned by this method is
* located in the concatenation of the location, package name, and
* relative name or next to the sibling argument. See {@link
* #getFileForInput getFileForInput} for an example.
*
* @param location a location
* @param packageName a package name
* @param relativeName a relative name
* @param sibling a file object to be used as hint for placement;
* might be {@code null}
* @return a file object
* @throws IllegalArgumentException if sibling is not known to
* this file manager, or if the location is not known to this file
* manager and the file manager does not support unknown
* locations, or if {@code relativeName} is not valid
* @throws IOException if an I/O error occurred, or if {@link
* #close} has been called and this file manager cannot be
* reopened
* @throws IllegalStateException if {@link #close} has been called
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