--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/java/io/FileOutputStream.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,469 @@
+/*
+ * Copyright (c) 1994, 2017, 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.channels.FileChannel;
+import jdk.internal.misc.SharedSecrets;
+import jdk.internal.misc.JavaIOFileDescriptorAccess;
+import sun.nio.ch.FileChannelImpl;
+
+
+/**
+ * A file output stream is an output stream for writing data to a
+ * <code>File</code> or to a <code>FileDescriptor</code>. 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</code> is meant for writing streams of raw bytes
+ * such as image data. For writing streams of characters, consider using
+ * <code>FileWriter</code>.
+ *
+ * @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 fdAccess =
+ SharedSecrets.getJavaIOFileDescriptorAccess();
+
+ /**
+ * 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;
+
+ /**
+ * Creates a file output stream to write to the file with the
+ * specified name. A new <code>FileDescriptor</code> object is
+ * created to represent this file connection.
+ * <p>
+ * First, if there is a security manager, its <code>checkWrite</code>
+ * method is called with <code>name</code> as its argument.
+ * <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</code> 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
+ * @exception 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
+ * @exception SecurityException if a security manager exists and its
+ * <code>checkWrite</code> method denies write access
+ * to the file.
+ * @see java.lang.SecurityManager#checkWrite(java.lang.String)
+ */
+ 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 second argument is <code>true</code>, then
+ * bytes will be written to the end of the file rather than the beginning.
+ * A new <code>FileDescriptor</code> object is created to represent this
+ * file connection.
+ * <p>
+ * First, if there is a security manager, its <code>checkWrite</code>
+ * method is called with <code>name</code> as its argument.
+ * <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</code> is thrown.
+ *
+ * @param name the system-dependent file name
+ * @param append if <code>true</code>, then bytes will be written
+ * to the end of the file rather than the beginning
+ * @exception 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.
+ * @exception SecurityException if a security manager exists and its
+ * <code>checkWrite</code> method denies write access
+ * to the file.
+ * @see java.lang.SecurityManager#checkWrite(java.lang.String)
+ * @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</code> object. A new
+ * <code>FileDescriptor</code> object is created to represent this
+ * file connection.
+ * <p>
+ * First, if there is a security manager, its <code>checkWrite</code>
+ * method is called with the path represented by the <code>file</code>
+ * argument as its argument.
+ * <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</code> is thrown.
+ *
+ * @param file the file to be opened for writing.
+ * @exception 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
+ * @exception SecurityException if a security manager exists and its
+ * <code>checkWrite</code> method denies write access
+ * to the file.
+ * @see java.io.File#getPath()
+ * @see java.lang.SecurityException
+ * @see java.lang.SecurityManager#checkWrite(java.lang.String)
+ */
+ 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</code> object. If the second argument is
+ * <code>true</code>, then bytes will be written to the end of the file
+ * rather than the beginning. A new <code>FileDescriptor</code> object is
+ * created to represent this file connection.
+ * <p>
+ * First, if there is a security manager, its <code>checkWrite</code>
+ * method is called with the path represented by the <code>file</code>
+ * argument as its argument.
+ * <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</code> is thrown.
+ *
+ * @param file the file to be opened for writing.
+ * @param append if <code>true</code>, then bytes will be written
+ * to the end of the file rather than the beginning
+ * @exception 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
+ * @exception SecurityException if a security manager exists and its
+ * <code>checkWrite</code> method denies write access
+ * to the file.
+ * @see java.io.File#getPath()
+ * @see java.lang.SecurityException
+ * @see java.lang.SecurityManager#checkWrite(java.lang.String)
+ * @since 1.4
+ */
+ public FileOutputStream(File file, boolean append)
+ throws FileNotFoundException
+ {
+ String name = (file != null ? file.getPath() : null);
+ SecurityManager security = System.getSecurityManager();
+ if (security != null) {
+ security.checkWrite(name);
+ }
+ if (name == null) {
+ throw new NullPointerException();
+ }
+ if (file.isInvalid()) {
+ throw new FileNotFoundException("Invalid file path");
+ }
+ this.fd = new FileDescriptor();
+ fd.attach(this);
+ this.path = name;
+
+ open(name, append);
+ }
+
+ /**
+ * 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>
+ * First, if there is a security manager, its <code>checkWrite</code>
+ * method is called with the file descriptor <code>fdObj</code>
+ * argument as its argument.
+ * <p>
+ * If <code>fdObj</code> is null then a <code>NullPointerException</code>
+ * is thrown.
+ * <p>
+ * This constructor does not throw an exception if <code>fdObj</code>
+ * 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</code> is thrown.
+ *
+ * @param fdObj the file descriptor to be opened for writing
+ * @exception SecurityException if a security manager exists and its
+ * <code>checkWrite</code> method denies
+ * write access to the file descriptor
+ * @see java.lang.SecurityManager#checkWrite(java.io.FileDescriptor)
+ */
+ public FileOutputStream(FileDescriptor fdObj) {
+ SecurityManager security = System.getSecurityManager();
+ if (fdObj == null) {
+ throw new NullPointerException();
+ }
+ if (security != null) {
+ security.checkWrite(fdObj);
+ }
+ 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;
+
+ /**
+ * Writes the specified byte to this file output stream. Implements
+ * the <code>write</code> method of <code>OutputStream</code>.
+ *
+ * @param b the byte to be written.
+ * @exception IOException if an I/O error occurs.
+ */
+ public void write(int b) throws IOException {
+ write(b, fdAccess.getAppend(fd));
+ }
+
+ /**
+ * 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
+ * @exception IOException If an I/O error has occurred.
+ */
+ private native void writeBytes(byte b[], int off, int len, boolean append)
+ throws IOException;
+
+ /**
+ * Writes <code>b.length</code> bytes from the specified byte array
+ * to this file output stream.
+ *
+ * @param b the data.
+ * @exception IOException if an I/O error occurs.
+ */
+ public void write(byte b[]) throws IOException {
+ writeBytes(b, 0, b.length, fdAccess.getAppend(fd));
+ }
+
+ /**
+ * Writes <code>len</code> bytes from the specified byte array
+ * starting at offset <code>off</code> to this file output stream.
+ *
+ * @param b the data.
+ * @param off the start offset in the data.
+ * @param len the number of bytes to write.
+ * @exception IOException if an I/O error occurs.
+ */
+ public void write(byte b[], int off, int len) throws IOException {
+ writeBytes(b, off, len, fdAccess.getAppend(fd));
+ }
+
+ /**
+ * 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.
+ *
+ * @exception IOException if an I/O error occurs.
+ *
+ * @revised 1.4
+ * @spec JSR-51
+ */
+ 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();
+ }
+
+ fd.closeAll(new Closeable() {
+ public void close() throws IOException {
+ close0();
+ }
+ });
+ }
+
+ /**
+ * Returns the file descriptor associated with this stream.
+ *
+ * @return the <code>FileDescriptor</code> object that represents
+ * the connection to the file in the file system being used
+ * by this <code>FileOutputStream</code> object.
+ *
+ * @exception 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
+ * @spec JSR-51
+ */
+ public FileChannel getChannel() {
+ FileChannel fc = this.channel;
+ if (fc == null) {
+ synchronized (this) {
+ fc = this.channel;
+ if (fc == null) {
+ this.channel = fc = FileChannelImpl.open(fd, path, false, true, this);
+ 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;
+ }
+
+ /**
+ * Cleans up the connection to the file, and ensures that the
+ * <code>close</code> method of this file output stream is
+ * called when there are no more references to this stream.
+ *
+ * @deprecated The {@code finalize} method has been deprecated.
+ * Subclasses that override {@code finalize} in order to perform cleanup
+ * should be modified to use alternative cleanup mechanisms and
+ * to remove the overriding {@code finalize} method.
+ * When overriding the {@code finalize} method, its implementation must explicitly
+ * ensure that {@code super.finalize()} is invoked as described in {@link Object#finalize}.
+ * See the specification for {@link Object#finalize()} for further
+ * information about migration options.
+ * @exception IOException if an I/O error occurs.
+ * @see java.io.FileInputStream#close()
+ */
+ @Deprecated(since="9")
+ protected void finalize() throws IOException {
+ if (fd != null) {
+ if (fd == FileDescriptor.out || fd == FileDescriptor.err) {
+ flush();
+ } else {
+ /* if fd is shared, the references in FileDescriptor
+ * will ensure that finalizer is only called when
+ * safe to do so. All references using the fd have
+ * become unreachable. We can call close()
+ */
+ close();
+ }
+ }
+ }
+
+ private native void close0() throws IOException;
+
+ private static native void initIDs();
+
+ static {
+ initIDs();
+ }
+
+}