/*
* Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
* Free SoftwareFoundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.vfs;
import com.caucho.util.CharBuffer;
import java.io.CharConversionException;
import java.io.EOFException;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
public class StringWriter extends StreamImpl {
private WriteStream _ws;
private CharBuffer _cb;
public StringWriter()
{
}
public StringWriter(CharBuffer cb)
{
this._cb = cb;
}
/**
* Opens a write stream using this StringWriter as the resulting string
*/
public WriteStream openWrite()
{
if (_cb != null)
_cb.clear();
else
_cb = CharBuffer.allocate();
if (_ws == null)
_ws = new WriteStream(this);
else
_ws.init(this);
try {
_ws.setEncoding("utf-8");
} catch (UnsupportedEncodingException e) {
}
return _ws;
}
public String getString()
{
try {
_ws.close();
} catch (IOException e) {
}
String str = _cb.close();
_cb = null;
return str;
}
/**
* Returns true since StringWriter is for writing.
*/
public boolean canWrite()
{
return true;
}
/**
* Writes a utf-8 encoded buffer to the underlying string.
*
* @param buf byte buffer containing the bytes
* @param offset offset where to start writing
* @param length number of bytes to write
* @param isEnd true when the write is flushing a close.
*/
@Override
public void write(byte []buf, int offset, int length, boolean isEnd)
throws IOException
{
int end = offset + length;
while (offset < end) {
int ch1 = buf[offset++] & 0xff;
if (ch1 < 0x80)
_cb.append((char) ch1);
else if ((ch1 & 0xe0) == 0xc0) {
if (offset >= end)
throw new EOFException("unexpected end of file in utf8 character");
int ch2 = buf[offset++] & 0xff;
if ((ch2 & 0xc0) != 0x80)
throw new CharConversionException("illegal utf8 encoding");
_cb.append((char) (((ch1 & 0x1f) << 6) + (ch2 & 0x3f)));
}
else if ((ch1 & 0xf0) == 0xe0) {
if (offset + 1 >= end)
throw new EOFException("unexpected end of file in utf8 character");
int ch2 = buf[offset++] & 0xff;
int ch3 = buf[offset++] & 0xff;
if ((ch2 & 0xc0) != 0x80)
throw new CharConversionException("illegal utf8 encoding");
if ((ch3 & 0xc0) != 0x80)
throw new CharConversionException("illegal utf8 encoding");
_cb.append((char) (((ch1 & 0x1f) << 12) + ((ch2 & 0x3f) << 6) + (ch3 & 0x3f)));
}
else
throw new CharConversionException("illegal utf8 encoding at (" +
(int) ch1 + ")");
}
}
}