java.io

Class FileOutputStream

Implemented Interfaces:
AutoCloseable, Closeable, Flushable

public class FileOutputStream
extends OutputStream

This classes allows a stream of data to be written to a disk file or any open FileDescriptor.

Constructor Summary

FileOutputStream(File file)
This method initializes a FileOutputStream object to write to the specified File object.
FileOutputStream(File file, boolean append)
This method initializes a FileOutputStream object to write to the specified File object.
FileOutputStream(FileDescriptor fdObj)
This method initializes a FileOutputStream object to write to the file represented by the specified FileDescriptor object.
FileOutputStream(String path)
This method initializes a FileOutputStream object to write to the named file.
FileOutputStream(String path, boolean append)
This method initializes a FileOutputStream object to write to the named file.

Method Summary

void
close()
This method closes the underlying file.
protected void
finalize()
FileChannel
getChannel()
This method creates a java.nio.channels.FileChannel.
FileDescriptor
getFD()
This method returns a FileDescriptor object representing the file that is currently being written to
void
write(byte[] buf)
This method writes all the bytes in the specified array to the file.
void
write(byte[] buf, int offset, int len)
This method writes len bytes from the byte array buf to the file starting at index offset.
void
write(int b)
This method writes a single byte of data to the file.

Methods inherited from class java.io.OutputStream

close, flush, write, write, write

Methods inherited from class java.lang.Object

clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

FileOutputStream

public FileOutputStream(File file)
            throws SecurityException,
                   FileNotFoundException
This method initializes a FileOutputStream object to write to the specified File object. The file is created if it does not exist, and the bytes written are written starting at the beginning of the file.

Before opening a file, a security check is performed by calling the checkWrite method of the SecurityManager (if one exists) with the name of the file to be opened. An exception is thrown if writing is not allowed.

Parameters:
file - The File object this stream should write to
Throws:
SecurityException - If write access to the file is not allowed
FileNotFoundException - If a non-security error occurs

FileOutputStream

public FileOutputStream(File file,
                        boolean append)
            throws FileNotFoundException
This method initializes a FileOutputStream object to write to the specified File object. The file is created if it does not exist, and the bytes written are written starting at the beginning of the file if the append parameter is false. Otherwise bytes are written at the end of the file.

Before opening a file, a security check is performed by calling the checkWrite method of the SecurityManager (if one exists) with the name of the file to be opened. An exception is thrown if writing is not allowed.

Parameters:
file - The File object this stream should write to
append - true to append bytes to the end of the file, or false to write bytes to the beginning
Throws:
SecurityException - If write access to the file is not allowed
FileNotFoundException - If a non-security error occurs

FileOutputStream

public FileOutputStream(FileDescriptor fdObj)
            throws SecurityException
This method initializes a FileOutputStream object to write to the file represented by the specified FileDescriptor object. This method does not create any underlying disk file or reposition the file pointer of the given descriptor. It assumes that this descriptor is ready for writing as is.

Before opening a file, a security check is performed by calling the checkWrite method of the SecurityManager (if one exists) with the specified FileDescriptor as an argument. An exception is thrown if writing is not allowed.

Parameters:
fdObj - The FileDescriptor this stream should write to
Throws:
SecurityException - If write access to the file is not allowed

FileOutputStream

public FileOutputStream(String path)
            throws SecurityException,
                   FileNotFoundException
This method initializes a FileOutputStream object to write to the named file. The file is created if it does not exist, and the bytes written are written starting at the beginning of the file.

Before opening a file, a security check is performed by calling the checkWrite method of the SecurityManager (if one exists) with the name of the file to be opened. An exception is thrown if writing is not allowed.

Parameters:
path - The name of the file this stream should write to
Throws:
SecurityException - If write access to the file is not allowed
FileNotFoundException - If a non-security error occurs

FileOutputStream

public FileOutputStream(String path,
                        boolean append)
            throws SecurityException,
                   FileNotFoundException
This method initializes a FileOutputStream object to write to the named file. The file is created if it does not exist, and the bytes written are written starting at the beginning of the file if the append argument is false or at the end of the file if the append argument is true.

Before opening a file, a security check is performed by calling the checkWrite method of the SecurityManager (if one exists) with the name of the file to be opened. An exception is thrown if writing is not allowed.

Parameters:
path - The name of the file this stream should write to
append - true to append bytes to the end of the file, or false to write bytes to the beginning
Throws:
SecurityException - If write access to the file is not allowed
FileNotFoundException - If a non-security error occurs

Method Details

close

public void close()
            throws IOException
This method closes the underlying file. Any further attempts to write to this stream will likely generate an exception since the file is closed.
Specified by:
close in interface Closeable
close in interface AutoCloseable
Overrides:
close in interface OutputStream
Throws:
IOException - If an error occurs

finalize

protected void finalize()
            throws IOException
Overrides:
finalize in interface Object

getChannel

public FileChannel getChannel()
This method creates a java.nio.channels.FileChannel. Nio does not allow one to create a file channel directly. A file channel must be created by first creating an instance of Input/Output/RandomAccessFile and invoking the getChannel() method on it.

getFD

public final FileDescriptor getFD()
            throws IOException
This method returns a FileDescriptor object representing the file that is currently being written to
Returns:
A FileDescriptor object for this stream
Throws:
IOException - If an error occurs

write

public void write(byte[] buf)
            throws IOException
This method writes all the bytes in the specified array to the file.
Overrides:
write in interface OutputStream
Parameters:
buf - The array of bytes to write to the file
Throws:
IOException - If an error occurs

write

public void write(byte[] buf,
                  int offset,
                  int len)
            throws IOException
This method writes len bytes from the byte array buf to the file starting at index offset.
Overrides:
write in interface OutputStream
Parameters:
buf - The array of bytes to write to the file
offset - The offset into the array to start writing bytes from
len - The number of bytes to write to the file
Throws:
IOException - If an error occurs

write

public void write(int b)
            throws IOException
This method writes a single byte of data to the file.
Overrides:
write in interface OutputStream
Parameters:
b - The byte of data to write, passed as an int
Throws:
IOException - If an error occurs

FileOutputStream.java -- Writes to a file on disk. Copyright (C) 1998, 2001, 2003, 2004, 2005 Free Software Foundation, Inc. This file is part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Classpath 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 for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.