/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 1999 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xalan" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 1999, Lotus
* Development Corporation., http://www.lotus.com. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package org.apache.xalan.serialize;
import java.io.*;
/**
* This class writes ASCII to a byte stream as quickly as possible. For the
* moment it does not do buffering, though I reserve the right to do some
* buffering down the line if I can prove that it will be faster even if the
* output stream is buffered.
*/
public final class WriterToUTF8Buffered extends Writer
{
/** The byte stream to write to. (sc & sb remove final to compile in JDK 1.1.8) */
private OutputStream m_os;
/**
* The internal buffer where data is stored.
* (sc & sb remove final to compile in JDK 1.1.8)
*/
private byte buf[];
/**
* The number of valid bytes in the buffer. This value is always
* in the range <tt>0</tt> through <tt>buf.length</tt>; elements
* <tt>buf[0]</tt> through <tt>buf[count-1]</tt> contain valid
* byte data.
*/
private int count;
/**
* Create an buffered UTF-8 writer.
*
*
* @param out the underlying output stream.
*
* @throws UnsupportedEncodingException
*/
public WriterToUTF8Buffered(OutputStream out)
throws UnsupportedEncodingException
{
this(out, 8 * 1024);
}
/**
* Create an buffered UTF-8 writer to write data to the
* specified underlying output stream with the specified buffer
* size.
*
* @param out the underlying output stream.
* @param size the buffer size.
* @exception IllegalArgumentException if size <= 0.
*/
public WriterToUTF8Buffered(final OutputStream out, final int size)
{
m_os = out;
if (size <= 0)
{
throw new IllegalArgumentException("Buffer size <= 0");
}
buf = new byte[size];
count = 0;
}
/**
* Write a single character. The character to be written is contained in
* the 16 low-order bits of the given integer value; the 16 high-order bits
* are ignored.
*
* <p> Subclasses that intend to support efficient single-character output
* should override this method.
*
* @param c int specifying a character to be written.
* @exception IOException If an I/O error occurs
*/
public void write(final int c) throws IOException
{
if (count >= buf.length)
{
flushBuffer();
}
if (c < 0x80)
buf[count++] = (byte) (c);
else if (c < 0x800)
{
buf[count++] = (byte) (0xc0 + (c >> 6));
buf[count++] = (byte) (0x80 + (c & 0x3f));
}
else
{
buf[count++] = (byte) (0xe0 + (c >> 12));
buf[count++] = (byte) (0x80 + ((c >> 6) & 0x3f));
buf[count++] = (byte) (0x80 + (c & 0x3f));
}
}
/**
* Write a portion of an array of characters.
*
* @param chars Array of characters
* @param start Offset from which to start writing characters
* @param length Number of characters to write
*
* @exception IOException If an I/O error occurs
*
* @throws java.io.IOException
*/
private final void writeDirect(
final char chars[], final int start, final int length)
throws java.io.IOException
{
final OutputStream os = m_os;
int n = length+start;
for (int i = start; i < n; i++)
{
final char c = chars[i];
if (c < 0x80)
os.write(c);
else if (c < 0x800)
{
os.write(0xc0 + (c >> 6));
os.write(0x80 + (c & 0x3f));
}
else
{
os.write(0xe0 + (c >> 12));
os.write(0x80 + ((c >> 6) & 0x3f));
os.write(0x80 + (c & 0x3f));
}
}
}
/**
* Write a string.
*
* @param s String to be written
*
* @exception IOException If an I/O error occurs
*/
private final void writeDirect(final String s) throws IOException
{
final int n = s.length();
final OutputStream os = m_os;
for (int i = 0; i < n; i++)
{
final char c = s.charAt(i);
if (c < 0x80)
os.write(c);
else if (c < 0x800)
{
os.write(0xc0 + (c >> 6));
os.write(0x80 + (c & 0x3f));
}
else
{
os.write(0xe0 + (c >> 12));
os.write(0x80 + ((c >> 6) & 0x3f));
os.write(0x80 + (c & 0x3f));
}
}
}
/**
* Write a portion of an array of characters.
*
* @param chars Array of characters
* @param start Offset from which to start writing characters
* @param length Number of characters to write
*
* @exception IOException If an I/O error occurs
*
* @throws java.io.IOException
*/
public void write(final char chars[], final int start, final int length)
throws java.io.IOException
{
if (length >= buf.length)
{
/* If the request length exceeds the size of the output buffer,
flush the output buffer and then write the data directly.
In this way buffered streams will cascade harmlessly. */
flushBuffer();
writeDirect(chars, start, length);
return;
}
if (length > buf.length - count)
{
flushBuffer();
}
final OutputStream os = m_os;
int n = length+start;
for (int i = start; i < n; i++)
{
final char c = chars[i];
if (c < 0x80)
buf[count++] = (byte) (c);
else if (c < 0x800)
{
buf[count++] = (byte) (0xc0 + (c >> 6));
buf[count++] = (byte) (0x80 + (c & 0x3f));
}
else
{
buf[count++] = (byte) (0xe0 + (c >> 12));
buf[count++] = (byte) (0x80 + ((c >> 6) & 0x3f));
buf[count++] = (byte) (0x80 + (c & 0x3f));
}
}
}
/**
* Write a string.
*
* @param s String to be written
*
* @exception IOException If an I/O error occurs
*/
public void write(final String s) throws IOException
{
final int length = s.length();
if (length >= buf.length)
{
/* If the request length exceeds the size of the output buffer,
flush the output buffer and then write the data directly.
In this way buffered streams will cascade harmlessly. */
flushBuffer();
writeDirect(s);
return;
}
if (length > buf.length - count)
{
flushBuffer();
}
final OutputStream os = m_os;
for (int i = 0; i < length; i++)
{
final char c = s.charAt(i);
if (c < 0x80)
buf[count++] = (byte) (c);
else if (c < 0x800)
{
buf[count++] = (byte) (0xc0 + (c >> 6));
buf[count++] = (byte) (0x80 + (c & 0x3f));
}
else
{
buf[count++] = (byte) (0xe0 + (c >> 12));
buf[count++] = (byte) (0x80 + ((c >> 6) & 0x3f));
buf[count++] = (byte) (0x80 + (c & 0x3f));
}
}
}
/**
* Flush the internal buffer
*
* @throws IOException
*/
public void flushBuffer() throws IOException
{
if (count > 0)
{
m_os.write(buf, 0, count);
count = 0;
}
}
/**
* Flush the stream. If the stream has saved any characters from the
* various write() methods in a buffer, write them immediately to their
* intended destination. Then, if that destination is another character or
* byte stream, flush it. Thus one flush() invocation will flush all the
* buffers in a chain of Writers and OutputStreams.
*
* @exception IOException If an I/O error occurs
*
* @throws java.io.IOException
*/
public void flush() throws java.io.IOException
{
flushBuffer();
m_os.flush();
}
/**
* Close the stream, flushing it first. Once a stream has been closed,
* further write() or flush() invocations will cause an IOException to be
* thrown. Closing a previously-closed stream, however, has no effect.
*
* @exception IOException If an I/O error occurs
*
* @throws java.io.IOException
*/
public void close() throws java.io.IOException
{
flushBuffer();
m_os.close();
}
/**
* Get the output stream where the events will be serialized to.
*
* @return reference to the result stream, or null of only a writer was
* set.
*/
public OutputStream getOutputStream()
{
return m_os;
}
}