/*
* Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
* 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
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.nio.fs;
import java.nio.file.*;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.io.IOException;
import static sun.nio.fs.WindowsNativeDispatcher.*;
import static sun.nio.fs.WindowsConstants.*;
/**
* Windows implementation of DirectoryStream
*/
class WindowsDirectoryStream
implements DirectoryStream<Path>
{
private final WindowsPath dir;
private final DirectoryStream.Filter<? super Path> filter;
// handle to directory
private final long handle;
// first entry in the directory
private final String firstName;
// buffer for WIN32_FIND_DATA structure that receives information about file
private final NativeBuffer findDataBuffer;
private final Object closeLock = new Object();
// need closeLock to access these
private boolean isOpen = true;
private Iterator<Path> iterator;
WindowsDirectoryStream(WindowsPath dir, DirectoryStream.Filter<? super Path> filter)
throws IOException
{
this.dir = dir;
this.filter = filter;
try {
// Need to append * or \* to match entries in directory.
String search = dir.getPathForWin32Calls();
char last = search.charAt(search.length() -1);
if (last == ':' || last == '\\') {
search += "*";
} else {
search += "\\*";
}
FirstFile first = FindFirstFile(search);
this.handle = first.handle();
this.firstName = first.name();
this.findDataBuffer = WindowsFileAttributes.getBufferForFindData();
} catch (WindowsException x) {
if (x.lastError() == ERROR_DIRECTORY) {
throw new NotDirectoryException(dir.getPathForExceptionMessage());
}
x.rethrowAsIOException(dir);
// keep compiler happy
throw new AssertionError();
}
}
@Override
public void close()
throws IOException
{
synchronized (closeLock) {
if (!isOpen)
return;
isOpen = false;
}
findDataBuffer.release();
try {
FindClose(handle);
} catch (WindowsException x) {
x.rethrowAsIOException(dir);
}
}
@Override
public Iterator<Path> iterator() {
if (!isOpen) {
throw new IllegalStateException("Directory stream is closed");
}
synchronized (this) {
if (iterator != null)
throw new IllegalStateException("Iterator already obtained");
iterator = new WindowsDirectoryIterator(firstName);
return iterator;
}
}
private class WindowsDirectoryIterator implements Iterator<Path> {
private boolean atEof;
private String first;
private Path nextEntry;
private String prefix;
WindowsDirectoryIterator(String first) {
atEof = false;
this.first = first;
if (dir.needsSlashWhenResolving()) {
prefix = dir.toString() + "\\";
} else {
prefix = dir.toString();
}
}
// links to self and parent directories are ignored
private boolean isSelfOrParent(String name) {
return name.equals(".") || name.equals("..");
}
// applies filter and also ignores "." and ".."
private Path acceptEntry(String s, BasicFileAttributes attrs) {
Path entry = WindowsPath
.createFromNormalizedPath(dir.getFileSystem(), prefix + s, attrs);
try {
if (filter.accept(entry))
return entry;
} catch (IOException ioe) {
throw new DirectoryIteratorException(ioe);
}
return null;
}
// reads next directory entry
private Path readNextEntry() {
// handle first element returned by search
if (first != null) {
nextEntry = isSelfOrParent(first) ? null : acceptEntry(first, null);
first = null;
if (nextEntry != null)
return nextEntry;
}
for (;;) {
String name = null;
WindowsFileAttributes attrs;
// synchronize on closeLock to prevent close while reading
synchronized (closeLock) {
try {
if (isOpen) {
name = FindNextFile(handle, findDataBuffer.address());
}
} catch (WindowsException x) {
IOException ioe = x.asIOException(dir);
throw new DirectoryIteratorException(ioe);
}
// NO_MORE_FILES or stream closed
if (name == null) {
atEof = true;
return null;
}
// ignore link to self and parent directories
if (isSelfOrParent(name))
continue;
// grab the attributes from the WIN32_FIND_DATA structure
// (needs to be done while holding closeLock because close
// will release the buffer)
attrs = WindowsFileAttributes
.fromFindData(findDataBuffer.address());
}
// return entry if accepted by filter
Path entry = acceptEntry(name, attrs);
if (entry != null)
/**代码未完, 请加载全部代码(NowJava.com).**/