java.lang.Object | +--java.io.OutputStream | +--java.io.FileOutputStream
Safe: A file output stream is an output stream for writing data to a
File 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 using
FileWriter.
java.io.File,
java.io.FileDescriptor,
java.io.FileInputStreamFileOutputStream(File file)
File object.
FileOutputStream(File file,
boolean append)
File object.
FileOutputStream(FileDescriptor fdObj)
FileOutputStream(String name)
FileOutputStream(String name,
boolean append)
name.
void
close()
protected void
finalize()
close method of this file output stream is
called when there are no more references to this stream.
java.nio.channels.FileChannel
getChannel()
FileChannel
object associated with this file output stream.
void
write(byte[] b)
b.length bytes from the specified byte array
to this file output stream.
void
write(byte[] b,
int off,
int len)
len bytes from the specified byte array
starting at offset off to this file output stream.
private FileDescriptor fd
private java.nio.channels.FileChannel channel
private boolean append
public FileOutputStream(String name) throws FileNotFoundException
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.
name - the system-dependent filenamejava.lang.SecurityManager#checkWrite(java.lang.String)public FileOutputStream(String name, boolean append) throws FileNotFoundException
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.
name - the system-dependent file nameappend - if true, then bytes will be written
to the end of the file rather than the beginningjava.lang.SecurityManager#checkWrite(java.lang.String)public FileOutputStream(File file) throws FileNotFoundException
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.
file - the file to be opened for writing.java.io.File#getPath(),
java.lang.SecurityException,
java.lang.SecurityManager#checkWrite(java.lang.String)public FileOutputStream(File file, boolean append) throws FileNotFoundException
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.
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 beginningjava.io.File#getPath(),
java.lang.SecurityException,
java.lang.SecurityManager#checkWrite(java.lang.String)public FileOutputStream(FileDescriptor fdObj)
First, if there is a security manager, its checkWrite
method is called with the file descriptor fdObj
argument as its argument.
fdObj - the file descriptor to be opened for writingjava.lang.SecurityManager#checkWrite(java.io.FileDescriptor)private void open(String name) throws FileNotFoundException
name - name of file to be opened
FileNotFoundExceptionprivate void openAppend(String name) throws FileNotFoundException
name - name of file to be opened
FileNotFoundExceptionpublic void write(int b) throws IOException
write method of OutputStream.
write in class OutputStreamb - the byte to be written.
IOExceptionprivate void writeBytes(byte[] b, int off, int len) throws IOException
b - the data to be writtenoff - the start offset in the datalen - the number of bytes that are written
IOExceptionpublic void write(byte[] b) throws IOException
b.length bytes from the specified byte array
to this file output stream.
write in class OutputStreamb - the data.
IOExceptionjava.io.OutputStream#write(byte[], int, int)public void write(byte[] b, int off, int len) throws IOException
len bytes from the specified byte array
starting at offset off to this file output stream.
write in class OutputStreamb - the data.off - the start offset in the data.len - the number of bytes to write.
IOExceptionpublic void close() throws IOException
If this stream has an associated channel then the channel is closed as well.
close in class OutputStreampublic final FileDescriptor getFD() throws IOException
FileDescriptor object that represents
the connection to the file in the file system being used
by this FileOutputStream object.
IOExceptionjava.io.FileDescriptorpublic java.nio.channels.FileChannel getChannel()
FileChannel
object associated with this file output stream.
The initial position 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.
protected void finalize() throws IOException
close method of this file output stream is
called when there are no more references to this stream.
IOExceptionjava.io.FileInputStream#close()private void close0() throws IOException
private static void initIDs()