com.purplehillsbooks.streams

Class WriterUTF8OutputStream

java.lang.Object

java.io.OutputStream

com.purplehillsbooks.streams.WriterUTF8OutputStream

All Implemented Interfaces:

java.io.Closeable, java.io.Flushable, java.lang.AutoCloseable

public class WriterUTF8OutputStream
extends java.io.OutputStream

WriterUTF8OutputStream Lets say you have a Writer (such as the out object in a JSP) and you want to call a method that takes an OutputStream. While you can easily make a Writer on top of an OutputStream, this class is to allow you to go the other way, and "downgrade" a Writer to an OutputStream. It is an OutputStream, so it accepts byte oriented writes, which it converts to characters and writes to the wrapped writer. This does the proper conversion for UTF8 encoded byte stream to Unicode characters. Other encodings are not supported. Supports UTF-8, the ONLY encoding that guarantees that all characters in the UTF-16 based Writer can be expressed without loss of characters. Author: Keith Swenson Copyright: Keith Swenson, all rights reserved License: This code is made available under the GNU Lesser GPL license.

Constructor Summary

Constructors

Constructor and Description
WriterUTF8OutputStream(java.io.Writer writer) Composes an InputStream stream from any other Reader you may have around.

Method Summary

Modifier and Type	Method and Description
void	close() Closes the wrapped OutputStream and terminates output.
void	flush() Flush.
void	write(int b) Receives a byte value, converts properly to a UTF-16 character and writes it to the Writer.

Methods inherited from class java.io.OutputStream

write, write

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

WriterUTF8OutputStream

public WriterUTF8OutputStream(java.io.Writer writer)

Composes an InputStream stream from any other Reader you may have around.

Parameters:

writer - The object to write to. Must not be null.

Method Detail

write

public void write(int b)
           throws java.io.IOException

Receives a byte value, converts properly to a UTF-16 character and writes it to the Writer. If the value is less than 128 it is written directly. If more than 127 the character is saved and waits for the rest of the multibyte sequence before the resulting character is written.

Specified by:

write in class java.io.OutputStream

Parameters:

b - the value of the next byte of the UTF-8 stream to write.

Throws:

java.io.IOException - if the wrapped Writer fails to write

flush

public void flush()
           throws java.io.IOException

Flush. If called when part way through a multi-byte UTF-8 encoded sequence, then only the full characters written so far a flushd, and the fraction of a character waiting to be finished is held back.

Specified by:

flush in interface java.io.Flushable

Overrides:

flush in class java.io.OutputStream

Throws:

java.io.IOException - if the original Writer fails to be flushed

close

public void close()
           throws java.io.IOException

Closes the wrapped OutputStream and terminates output. If called when part way through a multi-byte UTF-8 encoded sequence, then only the full characters written so far a included in the output, and the fraction of a character left in the buffer is discarded without writing.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Overrides:

close in class java.io.OutputStream

Throws:

java.io.IOException - if the original Writer fails to be closed