public class FileOutputStream extends OutputStream
FileDescriptor
.Constructor and Description |
---|
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. |
Modifier and Type | Method and Description |
---|---|
void |
close()
This method closes the underlying file.
|
protected void |
finalize()
Called on an object by the Virtual Machine at most once,
at some point after the Object is determined unreachable
but before it is destroyed.
|
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.
|
flush
public FileOutputStream(String path, boolean append) throws SecurityException, FileNotFoundException
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.
path
- The name of the file this stream should write toappend
- true
to append bytes to the end of the file,
or false
to write bytes to the beginningSecurityException
- If write access to the file is not allowedFileNotFoundException
- If a non-security error occurspublic FileOutputStream(String path) throws SecurityException, FileNotFoundException
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.
path
- The name of the file this stream should write toSecurityException
- If write access to the file is not allowedFileNotFoundException
- If a non-security error occurspublic FileOutputStream(File file) throws SecurityException, FileNotFoundException
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.
file
- The File
object this stream should write toSecurityException
- If write access to the file is not allowedFileNotFoundException
- If a non-security error occurspublic FileOutputStream(File file, boolean append) throws FileNotFoundException
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.
file
- The File
object this stream should write toappend
- true
to append bytes to the end of the file,
or false
to write bytes to the beginningSecurityException
- If write access to the file is not allowedFileNotFoundException
- If a non-security error occurspublic FileOutputStream(FileDescriptor fdObj) throws SecurityException
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.
fdObj
- The FileDescriptor
this stream should write toSecurityException
- If write access to the file is not allowedprotected void finalize() throws IOException
Object
java.lang.ref
package.
Virtual Machines are free to not call this method if
they can determine that it does nothing important; for
example, if your class extends Object and overrides
finalize to do simply super.finalize()
.
finalize() will be called by a Thread
that has no
locks on any Objects, and may be called concurrently.
There are no guarantees on the order in which multiple
objects are finalized. This means that finalize() is
usually unsuited for performing actions that must be
thread-safe, and that your implementation must be
use defensive programming if it is to always work.
If an Exception is thrown from finalize() during garbage collection, it will be patently ignored and the Object will still be destroyed.
It is allowed, although not typical, for user code to call finalize() directly. User invocation does not affect whether automatic invocation will occur. It is also permitted, although not recommended, for a finalize() method to "revive" an object by making it reachable from normal code again.
Unlike constructors, finalize() does not get called
for an object's superclass unless the implementation
specifically calls super.finalize()
.
The default implementation does nothing.
finalize
in class Object
IOException
System.gc()
,
System.runFinalizersOnExit(boolean)
,
java.lang.ref
public final FileDescriptor getFD() throws IOException
FileDescriptor
object representing
the file that is currently being written toFileDescriptor
object for this streamIOException
- If an error occurspublic void write(int b) throws IOException
write
in class OutputStream
b
- The byte of data to write, passed as an int
IOException
- If an error occurspublic void write(byte[] buf) throws IOException
write
in class OutputStream
buf
- The array of bytes to write to the fileIOException
- If an error occurspublic void write(byte[] buf, int offset, int len) throws IOException
len
bytes from the byte array
buf
to the file starting at index offset
.write
in class OutputStream
buf
- The array of bytes to write to the fileoffset
- The offset into the array to start writing bytes fromlen
- The number of bytes to write to the fileIOException
- If an error occurspublic void close() throws IOException
close
in interface Closeable
close
in class OutputStream
IOException
- If an error occurspublic FileChannel getChannel()