/*
 
* Copyright (c) 1994, 2013, 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 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 <tt>FileOutputStream</tt> (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
   
JDK1.0
 
*/

public
class
FileOutputStream extends OutputStream
{
    
/**
     
* The system dependent file descriptor.
     
*/
    
private final FileDescriptor fd;

    
/**
     
* True if the file is opened for append.
     
*/
    
private final boolean append;

    
/**
     
* The associated channel, initialized lazily.
     
*/
    
private 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 = false;

    
/**
     
* 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.
     
*
     
* @param
      
name
   
the system-dependent filename
     
* @exception
  
FileNotFoundExceptionif 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
  
SecurityExceptionif 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.
     
*
     
* @paramname
        
the system-dependent file name
     
* @paramappend
      
if <code>true</code>, then bytes will be written
     
*
                   
to the end of the file rather than the beginning
     
* @exception
  
FileNotFoundExceptionif 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
  
SecurityExceptionif a security manager exists and its
     
*
               
<code>checkWrite</code> method denies write access
     
*
               
to the file.
     
* @see
        
java.lang.SecurityManager#checkWrite(java.lang.String)
     
* @sinceJDK1.1
     
*/

    
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
  
FileNotFoundExceptionif 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
  
SecurityExceptionif 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.
     
* @paramappend
      
if <code>true</code>, then bytes will be written
     
*
                   
to the end of the file rather than the beginning
     
* @exception
  
FileNotFoundExceptionif 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
  
SecurityExceptionif 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.append = append;
        
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
  
SecurityExceptionif 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.append = false;
        
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
   
bthe 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
  
IOExceptionif an I/O error occurs.
     
*/

    
public void write(int b) throws IOException {
        
write(b, append);
    
}

    
/**
     
* 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
  
IOExceptionif an I/O error occurs.
     
*/

    
public void write(byte b[]) throws IOException {
        
writeBytes(b, 0, b.length, append);
    
}

    
/**
     
* Writes <code>len</code> bytes from the specified byte array
     
* starting at offset <code>off</code> to this file output stream.
     
*
     
* @param
      
bthe data.
     
* @param
      
off
   
the start offset in the data.
     
* @param
      
len
   
the number of bytes to write.
     
* @exception
  
IOExceptionif an I/O error occurs.
     
*/

    
public void write(byte b[], int off, int len) throws IOException {
        
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.
     
*
     
* @exception
  
IOExceptionif an I/O error occurs.
     
*
     
* @revised 1.4
     
* @spec JSR-51
     
*/

    
public void close() throws IOException {
        
synchronized (closeLock) {
            
if (closed) {
                
return;
            
}
            
closed = true;
        
}

        
if (channel != null) {
            
channel.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
  
IOExceptionif 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() {
        
synchronized (this) {
            
if (channel == null) {
                
channel = FileChannelImpl.open(fd, path, false, true, append, this);
            
}
            
return channel;
        
}
    
}

    
/**
     
* 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.
     
*
     
* @exception
  
IOExceptionif an I/O error occurs.
     
* @see
        
java.io.FileInputStream#close()
     
*/

    
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();
    
}

}