/*
* JBoss, Home of Professional Open Source.
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA.
*/
package org.teiid.util;
import java.io.IOException;
import java.io.Reader;
import java.io.Writer;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLEventWriter;
import javax.xml.stream.XMLOutputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.events.XMLEvent;
import javax.xml.transform.stax.StAXSource;
import org.teiid.core.types.XMLType;
/**
* Provides a {@link Reader} adapter for StAX
*/
public class XMLReader extends Reader {
private static final int BUFFER_SIZE = 1<<13;
private int pos = 0;
private StringBuilder builder = new StringBuilder(BUFFER_SIZE);
private XMLEventReader reader;
private XMLEventWriter writer;
public XMLReader(StAXSource source, XMLOutputFactory outFactory) throws XMLStreamException {
reader = source.getXMLEventReader();
if (reader == null) {
this.reader = XMLType.getXmlInputFactory().createXMLEventReader(source.getXMLStreamReader());
}
this.writer = outFactory.createXMLEventWriter(new Writer() {
@Override
public void write(char[] cbuf, int off, int len) throws IOException {
builder.append(cbuf, off, len);
}
@Override
public void flush() throws IOException {
}
@Override
public void write(String str, int off, int len) throws IOException {
builder.append(str, off, len);
}
@Override
public void close() throws IOException {
}
});
}
@Override
public int read() throws IOException {
while (pos >= builder.length()) {
if (!reader.hasNext()) {
return -1;
}
if (builder.length() > BUFFER_SIZE) {
builder.setLength(0);
pos = 0;
}
try {
XMLEvent event = reader.nextEvent();
writer.add(event);
writer.flush();
} catch (XMLStreamException e) {
throw new IOException(e);
}
}
return builder.charAt(pos++);
}
@Override
public void close() throws IOException {
try {
reader.close();
} catch (XMLStreamException e) {
throw new IOException(e);
}
}
@Override
public int read(char[] cbuf, int off, int len) throws IOException {
int i = 0;
int c = 0;
for (i = 0; i < len; i++) {
c = read();
if (c == -1) {
if (i == 0) {
return -1;
}
break;
}
cbuf[i+off] = (char)c;
}
return i;
}
}