FileOutputStream (Java Platform SE 7 ) (original) (raw)

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 aFile or to a 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
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 usingFileWriter.
Since:
JDK1.0
See Also:
File, FileDescriptor, FileInputStream, Files.newOutputStream(java.nio.file.Path, java.nio.file.OpenOption...)

Constructor Summary

Constructors

Constructor and 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(FileDescriptor fdObj) 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.
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

Methods

Modifier and Type	Method and Description
void	close() Closes this file output stream and releases any system resources associated with this stream.
protected void	finalize() Cleans up the connection to the file, and ensures that theclose method of this file output stream is called when there are no more references to this stream.
FileChannel	getChannel() Returns the unique FileChannel object associated with this file output stream.
FileDescriptor	getFD() Returns the file descriptor 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](../../java/io/OutputStream.html "class in java.io")  
   `[flush](../../java/io/OutputStream.html#flush%28%29)`  
   * ### Methods inherited from class java.lang.[Object](../../java/lang/Object.html "class in java.lang")  
   `[clone](../../java/lang/Object.html#clone%28%29), [equals](../../java/lang/Object.html#equals%28java.lang.Object%29), [getClass](../../java/lang/Object.html#getClass%28%29), [hashCode](../../java/lang/Object.html#hashCode%28%29), [notify](../../java/lang/Object.html#notify%28%29), [notifyAll](../../java/lang/Object.html#notifyAll%28%29), [toString](../../java/lang/Object.html#toString%28%29), [wait](../../java/lang/Object.html#wait%28%29), [wait](../../java/lang/Object.html#wait%28long%29), [wait](../../java/lang/Object.html#wait%28long,%20int%29)`

Constructor Detail

 * #### FileOutputStream  
 public FileOutputStream([String](../../java/lang/String.html "class in java.lang") name)  
                  throws [FileNotFoundException](../../java/io/FileNotFoundException.html "class in java.io")  
 Creates a file output stream to write to the file with the specified name. A new `FileDescriptor` object is created to represent this file connection.  
  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](../../java/io/FileNotFoundException.html "class in java.io")` \- 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](../../java/lang/SecurityException.html "class in java.lang")` \- if a security manager exists and its`checkWrite` method denies write access to the file.  
 See Also:  
 [SecurityManager.checkWrite(java.lang.String)](../../java/lang/SecurityManager.html#checkWrite%28java.lang.String%29)  
 * #### FileOutputStream  
 public FileOutputStream([String](../../java/lang/String.html "class in java.lang") name,  
                 boolean append)  
                  throws [FileNotFoundException](../../java/io/FileNotFoundException.html "class in java.io")  
 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. A new `FileDescriptor` object is created to represent this file connection.  
  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](../../java/io/FileNotFoundException.html "class in java.io")` \- 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](../../java/lang/SecurityException.html "class in java.lang")` \- if a security manager exists and its`checkWrite` method denies write access to the file.  
 Since:  
 JDK1.1  
 See Also:  
 [SecurityManager.checkWrite(java.lang.String)](../../java/lang/SecurityManager.html#checkWrite%28java.lang.String%29)  
 * #### FileOutputStream  
 public FileOutputStream([File](../../java/io/File.html "class in java.io") file)  
                  throws [FileNotFoundException](../../java/io/FileNotFoundException.html "class in java.io")  
 Creates a file output stream to write to the file represented by the specified `File` object. A new`FileDescriptor` object is created to represent this file connection.  
  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](../../java/io/FileNotFoundException.html "class in java.io")` \- 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](../../java/lang/SecurityException.html "class in java.lang")` \- if a security manager exists and its`checkWrite` method denies write access to the file.  
 See Also:  
 [File.getPath()](../../java/io/File.html#getPath%28%29), [SecurityException](../../java/lang/SecurityException.html "class in java.lang"), [SecurityManager.checkWrite(java.lang.String)](../../java/lang/SecurityManager.html#checkWrite%28java.lang.String%29)  
 * #### FileOutputStream  
 public FileOutputStream([File](../../java/io/File.html "class in java.io") file,  
                 boolean append)  
                  throws [FileNotFoundException](../../java/io/FileNotFoundException.html "class in java.io")  
 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. A new `FileDescriptor` object is created to represent this file connection.  
  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](../../java/io/FileNotFoundException.html "class in java.io")` \- 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](../../java/lang/SecurityException.html "class in java.lang")` \- if a security manager exists and its`checkWrite` method denies write access to the file.  
 Since:  
 1.4  
 See Also:  
 [File.getPath()](../../java/io/File.html#getPath%28%29), [SecurityException](../../java/lang/SecurityException.html "class in java.lang"), [SecurityManager.checkWrite(java.lang.String)](../../java/lang/SecurityManager.html#checkWrite%28java.lang.String%29)  
 * #### FileOutputStream  
 public FileOutputStream([FileDescriptor](../../java/io/FileDescriptor.html "class in java.io") fdObj)  
 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.  
  First, if there is a security manager, its `checkWrite` method is called with the file descriptor `fdObj` argument as its argument.  
  If `fdObj` is null then a `NullPointerException` is thrown.  
  This constructor does not throw an exception if `fdObj` is [invalid](../../java/io/FileDescriptor.html#valid%28%29). However, if the methods are invoked on the resulting stream to attempt I/O on the stream, an `IOException` is thrown.  
 Parameters:  
 `fdObj` \- the file descriptor to be opened for writing  
 Throws:  
 `[SecurityException](../../java/lang/SecurityException.html "class in java.lang")` \- if a security manager exists and its`checkWrite` method denies write access to the file descriptor  
 See Also:  
 [SecurityManager.checkWrite(java.io.FileDescriptor)](../../java/lang/SecurityManager.html#checkWrite%28java.io.FileDescriptor%29)

Method Detail

* #### write  
public void write(int b)  
           throws [IOException](../../java/io/IOException.html "class in java.io")  
Writes the specified byte to this file output stream. Implements the `write` method of `OutputStream`.  
**Specified by:**  
`[write](../../java/io/OutputStream.html#write%28int%29)` in class `[OutputStream](../../java/io/OutputStream.html "class in java.io")`  
Parameters:  
`b` \- the byte to be written.  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- if an I/O error occurs.  
* #### write  
public void write(byte[] b)  
           throws [IOException](../../java/io/IOException.html "class in java.io")  
Writes `b.length` bytes from the specified byte array to this file output stream.  
**Overrides:**  
`[write](../../java/io/OutputStream.html#write%28byte[]%29)` in class `[OutputStream](../../java/io/OutputStream.html "class in java.io")`  
Parameters:  
`b` \- the data.  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- if an I/O error occurs.  
See Also:  
[OutputStream.write(byte\[\], int, int)](../../java/io/OutputStream.html#write%28byte[],%20int,%20int%29)  
* #### write  
public void write(byte[] b,  
         int off,  
         int len)  
           throws [IOException](../../java/io/IOException.html "class in java.io")  
Writes `len` bytes from the specified byte array starting at offset `off` to this file output stream.  
**Overrides:**  
`[write](../../java/io/OutputStream.html#write%28byte[],%20int,%20int%29)` in class `[OutputStream](../../java/io/OutputStream.html "class in java.io")`  
Parameters:  
`b` \- the data.  
`off` \- the start offset in the data.  
`len` \- the number of bytes to write.  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- if an I/O error occurs.  
* #### close  
public void close()  
           throws [IOException](../../java/io/IOException.html "class in java.io")  
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](../../java/io/Closeable.html#close%28%29)` in interface `[Closeable](../../java/io/Closeable.html "interface in java.io")`  
**Specified by:**  
`[close](../../java/lang/AutoCloseable.html#close%28%29)` in interface `[AutoCloseable](../../java/lang/AutoCloseable.html "interface in java.lang")`  
**Overrides:**  
`[close](../../java/io/OutputStream.html#close%28%29)` in class `[OutputStream](../../java/io/OutputStream.html "class in java.io")`  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- if an I/O error occurs.  
* #### getFD  
public final [FileDescriptor](../../java/io/FileDescriptor.html "class in java.io") getFD()  
                           throws [IOException](../../java/io/IOException.html "class in java.io")  
Returns the file descriptor associated with this stream.  
Returns:  
the `FileDescriptor` object that represents the connection to the file in the file system being used by this `FileOutputStream` object.  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- if an I/O error occurs.  
See Also:  
[FileDescriptor](../../java/io/FileDescriptor.html "class in java.io")  
* #### getChannel  
public [FileChannel](../../java/nio/channels/FileChannel.html "class in java.nio.channels") getChannel()  
Returns the unique [FileChannel](../../java/nio/channels/FileChannel.html "class in java.nio.channels") object associated with this file output stream.  
 The initial [position](../../java/nio/channels/FileChannel.html#position%28%29) 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.  
Returns:  
the file channel associated with this file output stream  
Since:  
1.4  
* #### finalize  
protected void finalize()  
                 throws [IOException](../../java/io/IOException.html "class in java.io")  
Cleans up the connection to the file, and ensures that the`close` method of this file output stream is called when there are no more references to this stream.  
**Overrides:**  
`[finalize](../../java/lang/Object.html#finalize%28%29)` in class `[Object](../../java/lang/Object.html "class in java.lang")`  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- if an I/O error occurs.  
See Also:  
[FileInputStream.close()](../../java/io/FileInputStream.html#close%28%29)

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FileOutputStream (Java Platform SE 7 ) (original) (raw)

Constructor Summary

Method Summary

Constructor Detail

Method Detail