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/OpenJDK 8

Class FileImageOutputStream

All Implemented Interfaces:
Closeable, DataInput, DataOutput, AutoCloseable, ImageInputStream, ImageOutputStream
public class FileImageOutputStream
extends ImageOutputStreamImpl

An implementation of ImageOutputStream that writes its output directly to a File or RandomAccessFile.

Fields

Fields inherited from class javax.imageio.stream.ImageInputStreamImpl

bitOffset, byteOrder, flushedPos, streamPos

Constructors

FileImageOutputStream

public FileImageOutputStream(File f)
                      throws FileNotFoundException,
                             IOException

Constructs a FileImageOutputStream that will write to a given File.

Parameters:
f - a File to write to.
Throws:
IllegalArgumentException - if f is null.
SecurityException - if a security manager exists and does not allow write access to the file.
FileNotFoundException - if f does not denote a regular file or it cannot be opened for reading and writing for any other reason.
IOException - if an I/O error occurs.

FileImageOutputStream

public FileImageOutputStream(RandomAccessFile raf)

Constructs a FileImageOutputStream that will write to a given RandomAccessFile.

Parameters:
raf - a RandomAccessFile to write to.
Throws:
IllegalArgumentException - if raf is null.

Methods

read

public int read()
         throws IOException

Description copied from class: ImageInputStreamImpl

Reads a single byte from the stream and returns it as an int between 0 and 255. If EOF is reached, -1 is returned.

Subclasses must provide an implementation for this method. The subclass implementation should update the stream position before exiting.

The bit offset within the stream must be reset to zero before the read occurs.

Specified by:
read in interface ImageInputStream
Specified by:
read in class ImageInputStreamImpl
Returns:
the value of the next byte in the stream, or -1 if EOF is reached.
Throws:
IOException - if the stream has been closed.

read

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

Description copied from class: ImageInputStreamImpl

Reads up to len bytes from the stream, and stores them into b starting at index off. If no bytes can be read because the end of the stream has been reached, -1 is returned.

The bit offset within the stream must be reset to zero before the read occurs.

Subclasses must provide an implementation for this method. The subclass implementation should update the stream position before exiting.

Specified by:
read in interface ImageInputStream
Specified by:
read in class ImageInputStreamImpl
Parameters:
b - an array of bytes to be written to.
off - the starting position within b to write to.
len - the maximum number of bytes to read.
Returns:
the number of bytes actually read, or -1 to indicate EOF.
Throws:
IOException - if an I/O error occurs.

write

public void write(int b)
           throws IOException

Description copied from interface: ImageOutputStream

Writes a single byte to the stream at the current position. The 24 high-order bits of b are ignored.

If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write. Implementers can use the flushBits method of ImageOutputStreamImpl to guarantee this.

Specified by:
write in interface DataOutput
Specified by:
write in interface ImageOutputStream
Specified by:
write in class ImageOutputStreamImpl
Parameters:
b - an int whose lower 8 bits are to be written.
Throws:
IOException - if an I/O error occurs.

write

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

Description copied from interface: ImageOutputStream

Writes a sequence of bytes to the stream at the current position. If len is 0, nothing is written. The byte b[off] is written first, then the byte b[off + 1], and so on.

If the bit offset within the stream is non-zero, the remainder of the current byte is padded with 0s and written out first. The bit offset will be 0 after the write. Implementers can use the flushBits method of ImageOutputStreamImpl to guarantee this.

Specified by:
write in interface DataOutput
Specified by:
write in interface ImageOutputStream
Specified by:
write in class ImageOutputStreamImpl
Parameters:
b - an array of bytes to be written.
off - the start offset in the data.
len - the number of bytes to write.
Throws:
IOException - if an I/O error occurs.

length

public long length()

Description copied from class: ImageInputStreamImpl

Returns -1L to indicate that the stream has unknown length. Subclasses must override this method to provide actual length information.

Specified by:
length in interface ImageInputStream
Overrides:
length in class ImageInputStreamImpl
Returns:
-1L to indicate unknown length.

seek

public void seek(long pos)
          throws IOException

Sets the current stream position and resets the bit offset to 0. It is legal to seeking past the end of the file; an EOFException will be thrown only if a read is performed. The file length will not be increased until a write is performed.

Specified by:
seek in interface ImageInputStream
Overrides:
seek in class ImageInputStreamImpl
Parameters:
pos - a long containing the desired file pointer position.
Throws:
IndexOutOfBoundsException - if pos is smaller than the flushed position.
IOException - if any other I/O error occurs.

close

public void close()
           throws IOException

Description copied from interface: ImageInputStream

Closes the stream. Attempts to access a stream that has been closed may result in IOExceptions or incorrect behavior. Calling this method may allow classes implementing this interface to release resources associated with the stream such as memory, disk space, or file descriptors.

Specified by:
close in interface Closeable
Specified by:
close in interface AutoCloseable
Specified by:
close in interface ImageInputStream
Overrides:
close in class ImageInputStreamImpl
Throws:
IOException - if an I/O error occurs.

finalize

protected void finalize()
                 throws Throwable

Finalizes this object prior to garbage collection. The close method is called to close any open input source. This method should not be called from application code.

Overrides:
finalize in class ImageInputStreamImpl
Throws:
Throwable - if an error occurs during superclass finalization.
See Also:
WeakReference, PhantomReference

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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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