Package java.io

Class FileOutputStream

java.lang.Object

java.io.OutputStream

java.io.FileOutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

public class FileOutputStream
extends OutputStream

A file output stream is an output stream for writing data to a File. 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 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.

FileOutputStream is meant for writing streams of raw bytes such as image data. For writing streams of characters, consider using FileWriter.

Since:

JDK1.0

See Also:

File, FileInputStream

Constructor Summary

Constructors

Constructor	Description
FileOutputStream(File file)	Creates a file output stream to write to the file represented by the specified File object.
FileOutputStream(File file, boolean append)	Creates a file output stream to write to the file represented by the specified File object.
FileOutputStream(String name)	Creates a file output stream to write to the file with the specified name.
FileOutputStream(String name, boolean append)	Creates a file output stream to write to the file with the specified name.

Method Summary

Modifier and Type	Method	Description
void	close()	Closes this file output stream and releases any system resources associated with this stream.
void	write(byte[] b)	Writes b.length bytes from the specified byte array to this file output stream.
void	write(byte[] b, int off, int len)	Writes len bytes from the specified byte array starting at offset off to this file output stream.
void	write(int b)	Writes the specified byte to this file output stream.

Methods inherited from class java.io.OutputStream

flush

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FileOutputStream

public FileOutputStream(String name)
                 throws FileNotFoundException

Creates a file output stream to write to the file with the specified name.

First, if there is a security manager, its checkWrite method is called with name as its argument.

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 FileNotFoundException is thrown.

Parameters:

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

SecurityException - if a security manager exists and its checkWrite method denies write access to the file.

FileOutputStream

public FileOutputStream(String name,
                        boolean append)
                 throws FileNotFoundException

Creates a file output stream to write to the file with the specified name. If the second argument is true, then bytes will be written to the end of the file rather than the beginning.

First, if there is a security manager, its checkWrite method is called with name as its argument.

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 FileNotFoundException is thrown.

Parameters:

name - the system-dependent file name

append - if 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.

SecurityException - if a security manager exists and its checkWrite method denies write access to the file.

Since:

JDK1.1

FileOutputStream

public FileOutputStream(File file)
                 throws FileNotFoundException

Creates a file output stream to write to the file represented by the specified File object.

First, if there is a security manager, its checkWrite method is called with the path represented by the file argument as its argument.

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 FileNotFoundException is thrown.

Parameters:

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

SecurityException - if a security manager exists and its checkWrite method denies write access to the file.

See Also:

File.getPath(), SecurityException

FileOutputStream

public FileOutputStream(File file,
                        boolean append)
                 throws FileNotFoundException

Creates a file output stream to write to the file represented by the specified File object. If the second argument is true, then bytes will be written to the end of the file rather than the beginning.

First, if there is a security manager, its checkWrite method is called with the path represented by the file argument as its argument.

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 FileNotFoundException is thrown.

Parameters:

file - the file to be opened for writing.

append - if 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

SecurityException - if a security manager exists and its checkWrite method denies write access to the file.

Since:

1.4

See Also:

File.getPath(), SecurityException

Method Detail

write

public void write(int b)
           throws IOException

Writes the specified byte to this file output stream. Implements the write method of OutputStream.

Specified by:

write in class OutputStream

Parameters:

b - the byte to be written.

Throws:

IOException - if an I/O error occurs.

write

public void write(byte[] b)
           throws IOException

Writes b.length bytes from the specified byte array to this file output stream.

Overrides:

write in class OutputStream

Parameters:

b - the data.

Throws:

IOException - if an I/O error occurs.

See Also:

OutputStream.write(byte[], int, int)

write

public void write(byte[] b,
                  int off,
                  int len)
           throws IOException

Writes len bytes from the specified byte array starting at offset off to this file output stream.

Overrides:

write in class OutputStream

Parameters:

b - the data.

off - the start offset in the data.

len - the number of bytes to write.

Throws:

IOException - if an I/O error occurs.

close

public void close()
           throws IOException

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.

If this stream has an associated channel then the channel is closed as well.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class OutputStream

Throws:

IOException - if an I/O error occurs.