Prev Class | Next Class | Frames | No Frames |
Summary: Nested | Field | Method | Constr | Detail: Nested | Field | Method | Constr |
java.lang.Object
java.io.OutputStream
java.io.FileOutputStream
public class FileOutputStream
extends OutputStream
FileDescriptor
.
Constructor Summary | |
| |
| |
| |
| |
|
Method Summary | |
void |
|
protected void |
|
FileChannel |
|
FileDescriptor |
|
void |
|
void |
|
void |
|
Methods inherited from class java.lang.Object | |
clone , equals , extends Object> getClass , finalize , hashCode , notify , notifyAll , toString , wait , wait , wait |
public FileOutputStream(File file) throws SecurityException, FileNotFoundException
This method initializes aFileOutputStream
object to write to the specifiedFile
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 theSecurityManager
(if one exists) with the name of the file to be opened. An exception is thrown if writing is not allowed.
- Parameters:
file
- TheFile
object this stream should write to
- Throws:
SecurityException
- If write access to the file is not allowedFileNotFoundException
- If a non-security error occurs
public FileOutputStream(File file, boolean append) throws FileNotFoundException
This method initializes aFileOutputStream
object to write to the specifiedFile
object. The file is created if it does not exist, and the bytes written are written starting at the beginning of the file if theappend
parameter isfalse
. 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 theSecurityManager
(if one exists) with the name of the file to be opened. An exception is thrown if writing is not allowed.
- Parameters:
file
- TheFile
object this stream should write toappend
-true
to append bytes to the end of the file, orfalse
to write bytes to the beginning
- Throws:
SecurityException
- If write access to the file is not allowedFileNotFoundException
- If a non-security error occurs
public FileOutputStream(FileDescriptor fdObj) throws SecurityException
This method initializes aFileOutputStream
object to write to the file represented by the specifiedFileDescriptor
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 theSecurityManager
(if one exists) with the specifiedFileDescriptor
as an argument. An exception is thrown if writing is not allowed.
- Parameters:
fdObj
- TheFileDescriptor
this stream should write to
- Throws:
SecurityException
- If write access to the file is not allowed
public FileOutputStream(String path) throws SecurityException, FileNotFoundException
This method initializes aFileOutputStream
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 theSecurityManager
(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 allowedFileNotFoundException
- If a non-security error occurs
public FileOutputStream(String path, boolean append) throws SecurityException, FileNotFoundException
This method initializes aFileOutputStream
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 theappend
argument isfalse
or at the end of the file if theappend
argument is true.Before opening a file, a security check is performed by calling the
checkWrite
method of theSecurityManager
(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 toappend
-true
to append bytes to the end of the file, orfalse
to write bytes to the beginning
- Throws:
SecurityException
- If write access to the file is not allowedFileNotFoundException
- If a non-security error occurs
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
protected void finalize() throws IOException
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. You would think that this means it eventually is called on every Object, but this is not necessarily the case. If execution terminates abnormally, garbage collection does not always happen. Thus you cannot rely on this method to always work. For finer control over garbage collection, use references from thejava.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.
- See Also:
System.gc()
,System.runFinalizersOnExit(boolean)
,java.lang.ref
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.
public final FileDescriptor getFD() throws IOException
This method returns aFileDescriptor
object representing the file that is currently being written to
- Returns:
- A
FileDescriptor
object for this stream
- Throws:
IOException
- If an error occurs
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
public void write(byte[] buf, int offset, int len) throws IOException
This method writeslen
bytes from the byte arraybuf
to the file starting at indexoffset
.
- Overrides:
- write in interface OutputStream
- Parameters:
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 file
- Throws:
IOException
- If an error occurs
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 anint
- Throws:
IOException
- If an error occurs