mirror of
https://github.com/JetBrains/JetBrainsRuntime.git
synced 2026-02-05 07:06:32 +01:00
fbfee8b2be
It doesn't happen in any default implementation with default attribute classes, but some 3rd party implementations can do that.
568 lines
22 KiB
Java
568 lines
22 KiB
Java
/*
|
|
* Copyright (c) 1994, 2025, 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 java.io;
|
|
|
|
import java.nio.ByteBuffer;
|
|
import java.nio.channels.FileChannel;
|
|
import java.nio.file.Files;
|
|
import java.nio.file.OpenOption;
|
|
import java.nio.file.Path;
|
|
import java.nio.file.StandardOpenOption;
|
|
import java.nio.file.attribute.DosFileAttributeView;
|
|
import java.nio.file.attribute.DosFileAttributes;
|
|
import java.util.Set;
|
|
|
|
import com.jetbrains.internal.IoOverNio;
|
|
import jdk.internal.access.SharedSecrets;
|
|
import jdk.internal.access.JavaIOFileDescriptorAccess;
|
|
import jdk.internal.event.FileWriteEvent;
|
|
import sun.nio.ch.FileChannelImpl;
|
|
import static com.jetbrains.internal.IoOverNio.DEBUG;
|
|
|
|
|
|
/**
|
|
* A file output stream is an output stream for writing data to a
|
|
* {@code File} or to a {@code FileDescriptor}. Whether or not
|
|
* a file is available or may be created depends upon the underlying
|
|
* platform. Some platforms, in particular, allow a file to be opened
|
|
* for writing by only one {@code FileOutputStream} (or other
|
|
* file-writing object) at a time. In such situations the constructors in
|
|
* this class will fail if the file involved is already open.
|
|
*
|
|
* <p>{@code FileOutputStream} is meant for writing streams of raw bytes
|
|
* such as image data. For writing streams of characters, consider using
|
|
* {@code FileWriter}.
|
|
*
|
|
* @apiNote
|
|
* The {@link #close} method should be called to release resources used by this
|
|
* stream, either directly, or with the {@code try}-with-resources statement.
|
|
*
|
|
* @implSpec
|
|
* Subclasses are responsible for the cleanup of resources acquired by the subclass.
|
|
* Subclasses requiring that resource cleanup take place after a stream becomes
|
|
* unreachable should use {@link java.lang.ref.Cleaner} or some other mechanism.
|
|
*
|
|
* @author Arthur van Hoff
|
|
* @see java.io.File
|
|
* @see java.io.FileDescriptor
|
|
* @see java.io.FileInputStream
|
|
* @see java.nio.file.Files#newOutputStream
|
|
* @since 1.0
|
|
*/
|
|
public class FileOutputStream extends OutputStream
|
|
{
|
|
/**
|
|
* Access to FileDescriptor internals.
|
|
*/
|
|
private static final JavaIOFileDescriptorAccess FD_ACCESS =
|
|
SharedSecrets.getJavaIOFileDescriptorAccess();
|
|
|
|
/**
|
|
* Flag set by jdk.internal.event.JFRTracing to indicate if
|
|
* file writes should be traced by JFR.
|
|
*/
|
|
private static boolean jfrTracing;
|
|
|
|
/**
|
|
* The system dependent file descriptor.
|
|
*/
|
|
private final FileDescriptor fd;
|
|
|
|
/**
|
|
* The associated channel, initialized lazily.
|
|
*/
|
|
private volatile FileChannel channel;
|
|
|
|
/**
|
|
* The path of the referenced file
|
|
* (null if the stream is created with a file descriptor)
|
|
*/
|
|
private final String path;
|
|
|
|
private final Object closeLock = new Object();
|
|
|
|
private volatile boolean closed;
|
|
|
|
private final boolean useNio;
|
|
|
|
@SuppressWarnings({
|
|
"FieldCanBeLocal",
|
|
"this-escape", // It immediately converts into a phantom reference.
|
|
})
|
|
private final NioChannelCleanable channelCleanable = new NioChannelCleanable(this);
|
|
|
|
private final ExternalChannelHolder externalChannelHolder;
|
|
|
|
/**
|
|
* Creates a file output stream to write to the file with the
|
|
* specified name. If the file exists, it is truncated, otherwise a
|
|
* new file is created. {@linkplain java.nio.file##links Symbolic links}
|
|
* are automatically redirected to the <i>target</i> of the link.
|
|
* A new {@code FileDescriptor} object is
|
|
* created to represent this file connection.
|
|
* <p>
|
|
* If the file exists but is a directory rather than a regular file, does
|
|
* not exist but cannot be created, or cannot be opened for any other
|
|
* reason then a {@code FileNotFoundException} is thrown.
|
|
*
|
|
* @implSpec Invoking this constructor with the parameter {@code name} is
|
|
* equivalent to invoking {@link #FileOutputStream(String,boolean)
|
|
* new FileOutputStream(name, false)}.
|
|
*
|
|
* @param name the system-dependent filename
|
|
* @throws FileNotFoundException if the file exists but is a directory
|
|
* rather than a regular file, does not exist but cannot
|
|
* be created, or cannot be opened for any other reason
|
|
*/
|
|
public FileOutputStream(String name) throws FileNotFoundException {
|
|
this(name != null ? new File(name) : null, false);
|
|
}
|
|
|
|
/**
|
|
* Creates a file output stream to write to the file with the specified
|
|
* name. If the file exists, it is truncated unless the second
|
|
* argument is {@code true}, in which case bytes will be written to the
|
|
* end of the file rather than the beginning. If the file does not exist,
|
|
* it is created. {@linkplain java.nio.file##links Symbolic links}
|
|
* are automatically redirected to the <i>target</i> of the link.
|
|
* A new {@code FileDescriptor} object is created to represent this
|
|
* file connection.
|
|
* <p>
|
|
* If the file exists but is a directory rather than a regular file, does
|
|
* not exist but cannot be created, or cannot be opened for any other
|
|
* reason then a {@code FileNotFoundException} is thrown.
|
|
*
|
|
* @param name the system-dependent file name
|
|
* @param append if {@code true}, then bytes will be written
|
|
* to the end of the file rather than the beginning
|
|
* @throws FileNotFoundException if the file exists but is a directory
|
|
* rather than a regular file, does not exist but cannot
|
|
* be created, or cannot be opened for any other reason.
|
|
* @since 1.1
|
|
*/
|
|
public FileOutputStream(String name, boolean append)
|
|
throws FileNotFoundException
|
|
{
|
|
this(name != null ? new File(name) : null, append);
|
|
}
|
|
|
|
/**
|
|
* Creates a file output stream to write to the file represented by
|
|
* the specified {@code File} object.
|
|
* If the file exists, it is truncated, otherwise a
|
|
* new file is created. {@linkplain java.nio.file##links Symbolic links}
|
|
* are automatically redirected to the <i>target</i> of the link.
|
|
* A new {@code FileDescriptor} object is
|
|
* created to represent this file connection.
|
|
* <p>
|
|
* If the file exists but is a directory rather than a regular file, does
|
|
* not exist but cannot be created, or cannot be opened for any other
|
|
* reason then a {@code FileNotFoundException} is thrown.
|
|
*
|
|
* @param file the file to be opened for writing.
|
|
* @throws FileNotFoundException if the file exists but is a directory
|
|
* rather than a regular file, does not exist but cannot
|
|
* be created, or cannot be opened for any other reason
|
|
* @see java.io.File#getPath()
|
|
*/
|
|
public FileOutputStream(File file) throws FileNotFoundException {
|
|
this(file, false);
|
|
}
|
|
|
|
/**
|
|
* Creates a file output stream to write to the file represented by
|
|
* the specified {@code File} object.
|
|
* If the file exists, it is truncated unless the second
|
|
* argument is {@code true}, in which case bytes will be written to the
|
|
* end of the file rather than the beginning. If the file does not exist,
|
|
* it is created. {@linkplain java.nio.file##links Symbolic links}
|
|
* are automatically redirected to the <i>target</i> of the link.
|
|
* A new {@code FileDescriptor} object is created to represent this
|
|
* file connection.
|
|
* <p>
|
|
* If the file exists but is a directory rather than a regular file, does
|
|
* not exist but cannot be created, or cannot be opened for any other
|
|
* reason then a {@code FileNotFoundException} is thrown.
|
|
*
|
|
* @param file the file to be opened for writing.
|
|
* @param append if {@code true}, then bytes will be written
|
|
* to the end of the file rather than the beginning
|
|
* @throws FileNotFoundException if the file exists but is a directory
|
|
* rather than a regular file, does not exist but cannot
|
|
* be created, or cannot be opened for any other reason
|
|
* @see java.io.File#getPath()
|
|
* @since 1.4
|
|
*/
|
|
@SuppressWarnings("this-escape")
|
|
public FileOutputStream(File file, boolean append)
|
|
throws FileNotFoundException
|
|
{
|
|
if (file.isInvalid()) {
|
|
throw new FileNotFoundException("Invalid file path");
|
|
}
|
|
this.path = file.getPath();
|
|
|
|
java.nio.file.FileSystem nioFs = IoOverNioFileSystem.acquireNioFs(path);
|
|
useNio = path != null && nioFs != null;
|
|
if (useNio) {
|
|
Path nioPath = nioFs.getPath(path);
|
|
|
|
// java.io backend doesn't open DOS hidden files for writing, but java.nio.file opens.
|
|
// This code mimics the old behavior.
|
|
if (nioFs.getSeparator().equals("\\")) {
|
|
DosFileAttributes attrs = null;
|
|
try {
|
|
var view = Files.getFileAttributeView(nioPath, DosFileAttributeView.class);
|
|
if (view != null) {
|
|
attrs = view.readAttributes();
|
|
}
|
|
} catch (IOException | UnsupportedOperationException _) {
|
|
// Windows paths without DOS attributes? Not a problem in this case.
|
|
}
|
|
if (attrs != null && (attrs.isHidden() || attrs.isDirectory())) {
|
|
throw new FileNotFoundException(file.getPath() + " (Access is denied)");
|
|
}
|
|
}
|
|
|
|
Set<OpenOption> options = append
|
|
? Set.of(StandardOpenOption.WRITE, StandardOpenOption.CREATE, StandardOpenOption.APPEND)
|
|
: Set.of(StandardOpenOption.WRITE, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING);
|
|
var bundle = IoOverNioFileSystem.initializeStreamUsingNio(
|
|
this, nioFs, file, nioPath, options, channelCleanable);
|
|
channel = bundle.channel();
|
|
fd = bundle.fd();
|
|
externalChannelHolder = bundle.externalChannelHolder();
|
|
} else {
|
|
this.fd = new FileDescriptor();
|
|
fd.attach(this);
|
|
|
|
open(this.path, append);
|
|
FileCleanable.register(fd); // open sets the fd, register the cleanup
|
|
externalChannelHolder = null;
|
|
}
|
|
if (DEBUG.writeTraces()) {
|
|
System.err.printf("Created a FileOutputStream for %s%n", file);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Creates a file output stream to write to the specified file
|
|
* descriptor, which represents an existing connection to an actual
|
|
* file in the file system.
|
|
* <p>
|
|
* If {@code fdObj} is null then a {@code NullPointerException}
|
|
* is thrown.
|
|
* <p>
|
|
* This constructor does not throw an exception if {@code fdObj}
|
|
* is {@link java.io.FileDescriptor#valid() invalid}.
|
|
* However, if the methods are invoked on the resulting stream to attempt
|
|
* I/O on the stream, an {@code IOException} is thrown.
|
|
*
|
|
* @param fdObj the file descriptor to be opened for writing
|
|
*/
|
|
@SuppressWarnings("this-escape")
|
|
public FileOutputStream(FileDescriptor fdObj) {
|
|
useNio = false;
|
|
externalChannelHolder = null;
|
|
|
|
if (fdObj == null) {
|
|
throw new NullPointerException();
|
|
}
|
|
this.fd = fdObj;
|
|
this.path = null;
|
|
|
|
fd.attach(this);
|
|
}
|
|
|
|
/**
|
|
* Opens a file, with the specified name, for overwriting or appending.
|
|
* @param name name of file to be opened
|
|
* @param append whether the file is to be opened in append mode
|
|
*/
|
|
private native void open0(String name, boolean append)
|
|
throws FileNotFoundException;
|
|
|
|
// wrap native call to allow instrumentation
|
|
/**
|
|
* Opens a file, with the specified name, for overwriting or appending.
|
|
* @param name name of file to be opened
|
|
* @param append whether the file is to be opened in append mode
|
|
*/
|
|
private void open(String name, boolean append) throws FileNotFoundException {
|
|
open0(name, append);
|
|
}
|
|
|
|
/**
|
|
* Writes the specified byte to this file output stream.
|
|
*
|
|
* @param b the byte to be written.
|
|
* @param append {@code true} if the write operation first
|
|
* advances the position to the end of file
|
|
*/
|
|
private native void write(int b, boolean append) throws IOException;
|
|
|
|
private void traceWrite(int b, boolean append) throws IOException {
|
|
long bytesWritten = 0;
|
|
long start = FileWriteEvent.timestamp();
|
|
try {
|
|
start = FileWriteEvent.timestamp();
|
|
implWrite(b, append);
|
|
bytesWritten = 1;
|
|
} finally {
|
|
FileWriteEvent.offer(start, path, bytesWritten);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Writes the specified byte to this file output stream. Implements
|
|
* the {@code write} method of {@code OutputStream}.
|
|
*
|
|
* @param b the byte to be written.
|
|
* @throws IOException if an I/O error occurs.
|
|
*/
|
|
@Override
|
|
public void write(int b) throws IOException {
|
|
boolean append = FD_ACCESS.getAppend(fd);
|
|
if (jfrTracing && FileWriteEvent.enabled() && !IoOverNio.isAllowedInThisThread()) {
|
|
traceWrite(b, append);
|
|
return;
|
|
}
|
|
implWrite(b, append);
|
|
}
|
|
|
|
private void implWrite(int b, boolean append) throws IOException {
|
|
if (!useNio) {
|
|
write(b, append);
|
|
} else {
|
|
// 'append' is ignored; the channel is supposed to obey the mode in which the file was opened
|
|
byte[] array = new byte[1];
|
|
array[0] = (byte) b;
|
|
ByteBuffer buffer = ByteBuffer.wrap(array);
|
|
do {
|
|
channel.write(buffer);
|
|
} while (buffer.hasRemaining());
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Writes a sub array as a sequence of bytes.
|
|
* @param b the data to be written
|
|
* @param off the start offset in the data
|
|
* @param len the number of bytes that are written
|
|
* @param append {@code true} to first advance the position to the
|
|
* end of file
|
|
* @throws IOException If an I/O error has occurred.
|
|
*/
|
|
private native void writeBytes(byte[] b, int off, int len, boolean append)
|
|
throws IOException;
|
|
|
|
private void traceWriteBytes(byte b[], int off, int len, boolean append) throws IOException {
|
|
long bytesWritten = 0;
|
|
long start = FileWriteEvent.timestamp();
|
|
try {
|
|
start = FileWriteEvent.timestamp();
|
|
implWriteBytes(b, off, len, append);
|
|
bytesWritten = len;
|
|
} finally {
|
|
FileWriteEvent.offer(start, path, bytesWritten);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Writes {@code b.length} bytes from the specified byte array
|
|
* to this file output stream.
|
|
*
|
|
* @param b {@inheritDoc}
|
|
* @throws IOException {@inheritDoc}
|
|
*/
|
|
@Override
|
|
public void write(byte[] b) throws IOException {
|
|
boolean append = FD_ACCESS.getAppend(fd);
|
|
if (jfrTracing && FileWriteEvent.enabled() && !IoOverNio.isAllowedInThisThread()) {
|
|
traceWriteBytes(b, 0, b.length, append);
|
|
return;
|
|
}
|
|
|
|
implWriteBytes(b, 0, b.length, append);
|
|
}
|
|
|
|
/**
|
|
* Writes {@code len} bytes from the specified byte array
|
|
* starting at offset {@code off} to this file output stream.
|
|
*
|
|
* @param b {@inheritDoc}
|
|
* @param off {@inheritDoc}
|
|
* @param len {@inheritDoc}
|
|
* @throws IOException if an I/O error occurs.
|
|
* @throws IndexOutOfBoundsException {@inheritDoc}
|
|
*/
|
|
@Override
|
|
public void write(byte[] b, int off, int len) throws IOException {
|
|
boolean append = FD_ACCESS.getAppend(fd);
|
|
if (jfrTracing && FileWriteEvent.enabled() && !IoOverNio.isAllowedInThisThread()) {
|
|
traceWriteBytes(b, off, len, append);
|
|
return;
|
|
}
|
|
implWriteBytes(b, off, len, append);
|
|
}
|
|
|
|
private void implWriteBytes(byte[] b, int off, int len, boolean append) throws IOException {
|
|
if (!useNio) {
|
|
writeBytes(b, off, len, append);
|
|
} else {
|
|
// 'append' is ignored; the channel is supposed to obey the mode in which the file was opened
|
|
try {
|
|
ByteBuffer buffer = ByteBuffer.wrap(b, off, len);
|
|
do {
|
|
channel.write(buffer);
|
|
} while (buffer.hasRemaining());
|
|
} catch (OutOfMemoryError e) {
|
|
// May fail to allocate direct buffer memory due to small -XX:MaxDirectMemorySize
|
|
writeBytes(b, off, len, append);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Closes this file output stream and releases any system resources
|
|
* associated with this stream. This file output stream may no longer
|
|
* be used for writing bytes.
|
|
*
|
|
* <p> If this stream has an associated channel then the channel is closed
|
|
* as well.
|
|
*
|
|
* @apiNote
|
|
* Overriding {@link #close} to perform cleanup actions is reliable
|
|
* only when called directly or when called by try-with-resources.
|
|
*
|
|
* @implSpec
|
|
* Subclasses requiring that resource cleanup take place after a stream becomes
|
|
* unreachable should use the {@link java.lang.ref.Cleaner} mechanism.
|
|
*
|
|
* <p>
|
|
* If this stream has an associated channel then this method will close the
|
|
* channel, which in turn will close this stream. Subclasses that override
|
|
* this method should be prepared to handle possible reentrant invocation.
|
|
*
|
|
* @throws IOException if an I/O error occurs.
|
|
*/
|
|
@Override
|
|
public void close() throws IOException {
|
|
if (closed) {
|
|
return;
|
|
}
|
|
synchronized (closeLock) {
|
|
if (closed) {
|
|
return;
|
|
}
|
|
closed = true;
|
|
}
|
|
|
|
FileChannel fc = channel;
|
|
if (fc != null) {
|
|
// possible race with getChannel(), benign since
|
|
// FileChannel.close is final and idempotent
|
|
fc.close();
|
|
}
|
|
|
|
if (externalChannelHolder != null) {
|
|
externalChannelHolder.close();
|
|
}
|
|
|
|
fd.closeAll(new Closeable() {
|
|
public void close() throws IOException {
|
|
fd.close();
|
|
}
|
|
});
|
|
}
|
|
|
|
/**
|
|
* Returns the file descriptor associated with this stream.
|
|
*
|
|
* @return the {@code FileDescriptor} object that represents
|
|
* the connection to the file in the file system being used
|
|
* by this {@code FileOutputStream} object.
|
|
*
|
|
* @throws IOException if an I/O error occurs.
|
|
* @see java.io.FileDescriptor
|
|
*/
|
|
public final FileDescriptor getFD() throws IOException {
|
|
if (fd != null) {
|
|
return fd;
|
|
}
|
|
throw new IOException();
|
|
}
|
|
|
|
/**
|
|
* Returns the unique {@link java.nio.channels.FileChannel FileChannel}
|
|
* object associated with this file output stream.
|
|
*
|
|
* <p> The initial {@link java.nio.channels.FileChannel#position()
|
|
* position} of the returned channel will be equal to the
|
|
* number of bytes written to the file so far unless this stream is in
|
|
* append mode, in which case it will be equal to the size of the file.
|
|
* Writing bytes to this stream will increment the channel's position
|
|
* accordingly. Changing the channel's position, either explicitly or by
|
|
* writing, will change this stream's file position.
|
|
*
|
|
* @return the file channel associated with this file output stream
|
|
*
|
|
* @since 1.4
|
|
*/
|
|
public FileChannel getChannel() {
|
|
if (externalChannelHolder != null) {
|
|
return externalChannelHolder.getInterruptibleChannel();
|
|
}
|
|
|
|
FileChannel fc = this.channel;
|
|
if (fc == null) {
|
|
synchronized (this) {
|
|
fc = this.channel;
|
|
if (fc == null) {
|
|
fc = FileChannelImpl.open(fd, path, false, true, false, false, this);
|
|
this.channel = fc;
|
|
if (closed) {
|
|
try {
|
|
// possible race with close(), benign since
|
|
// FileChannel.close is final and idempotent
|
|
fc.close();
|
|
} catch (IOException ioe) {
|
|
throw new InternalError(ioe); // should not happen
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return fc;
|
|
}
|
|
|
|
private static native void initIDs();
|
|
|
|
static {
|
|
initIDs();
|
|
}
|
|
}
|