FilterOutputStream

This class is the superclass of all classes that filter output streams. These streams sit on top of an already existing output stream (the underlying output stream) which it uses as its basic sink of data, but possibly transforming the data along the way or providing additional functionality. The class <code>FilterOutputStream</code> itself simply overrides all methods of <code>OutputStream</code> with versions that pass all requests to the underlying output stream. Subclasses of <code>FilterOutputStream</code> may further override some of these methods as well as provide additional methods and fields.

@author Jonathan Payne

class FilterOutputStream : OutputStream {

protected

OutputStream outputStream;

this(OutputStream outputStream);

void write(int b);

void write(byte[] b);

void write(byte[] b, int off, int len);

void flush();

void close();

}

Constructors

this this(OutputStream outputStream): Creates an output stream filter built on top of the specified underlying output stream.

Members

Functions

close void close(): Closes this output stream and releases any system resources associated with the stream. When not already closed, the {@code close} method of {@code FilterOutputStream} calls its {@code flush} method, and then calls the {@code close} method of its underlying output stream.
flush void flush(): Flushes this output stream and forces any buffered output bytes to be written out to the stream. The <code>flush</code> method of <code>FilterOutputStream</code> calls the <code>flush</code> method of its underlying output stream.
write void write(int b): Writes the specified <code>byte</code> to this output stream. The <code>write</code> method of <code>FilterOutputStream</code> calls the <code>write</code> method of its underlying output stream, that is, it performs {@code outputStream.write(b)}. Implements the abstract {@code write} method of {@code OutputStream}.
write void write(byte[] b): Writes <code>b.length</code> bytes to this output stream. The <code>write</code> method of <code>FilterOutputStream</code> calls its <code>write</code> method of three arguments with the arguments <code>b</code>, <code>0</code>, and <code>b.length</code>. Note that this method does not call the one-argument <code>write</code> method of its underlying output stream with the single argument <code>b</code>.
write void write(byte[] b, int off, int len): Writes <code>len</code> bytes from the specified <code>byte</code> array starting at offset <code>off</code> to this output stream. The <code>write</code> method of <code>FilterOutputStream</code> calls the <code>write</code> method of one argument on each <code>byte</code> to output. Note that this method does not call the <code>write</code> method of its underlying output stream with the same arguments. Subclasses of <code>FilterOutputStream</code> should provide a more efficient implementation of this method.

Variables

outputStream OutputStream outputStream;: The underlying output stream to be filtered.

Inherited Members

From OutputStream

write void write(int b): Writes the specified byte to this output stream. The general contract for <code>write</code> is that one byte is written to the output stream. The byte to be written is the eight low-order bits of the argument <code>b</code>. The 24 high-order bits of <code>b</code> are ignored. Subclasses of <code>OutputStream</code> must provide an implementation for this method.
write void write(string b): Undocumented in source. Be warned that the author may not have intended to support it.
write void write(byte[] b): Writes <code>b.length</code> bytes from the specified byte array to this output stream. The general contract for <code>write(b)</code> is that it should have exactly the same effect as the call <code>write(b, 0, b.length)</code>.
write void write(byte[] b, int off, int len): Writes <code>len</code> bytes from the specified byte array starting at offset <code>off</code> to this output stream. The general contract for <code>write(b, off, len)</code> is that some of the bytes in the array <code>b</code> are written to the output stream in order; element <code>boff</code> is the first byte written and <code>b[off+len-1]</code> is the last byte written by this operation. The <code>write</code> method of <code>OutputStream</code> calls the write method of one argument on each of the bytes to be written out. Subclasses are encouraged to override this method and provide a more efficient implementation. If <code>b</code> is <code>null</code>, a <code>NullPointerException</code> is thrown. If <code>off</code> is negative, or <code>len</code> is negative, or <code>off+len</code> is greater than the length of the array <code>b</code>, then an <tt>IndexOutOfBoundsException</tt> is thrown.
flush void flush(): Flushes this output stream and forces any buffered output bytes to be written out. The general contract of <code>flush</code> is that calling it is an indication that, if any bytes previously written have been buffered by the implementation of the output stream, such bytes should immediately be written to their intended destination. If the intended destination of this stream is an abstraction provided by the underlying operating system, for example a file, then flushing the stream guarantees only that bytes previously written to the stream are passed to the operating system for writing; it does not guarantee that they are actually written to a physical device such as a disk drive. The <code>flush</code> method of <code>OutputStream</code> does nothing.
close void close(): Closes this output stream and releases any system resources associated with this stream. The general contract of <code>close</code> is that it closes the output stream. A closed stream cannot perform output operations and cannot be reopened. The <code>close</code> method of <code>OutputStream</code> does nothing.