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/*
Calimero 2 - A library for KNX network access
Copyright (c) 2006, 2017 B. Malinowsky
This program 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.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Linking this library statically or dynamically with other modules is
making a combined work based on this library. Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.
As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under terms
of your choice, provided that you also meet, for each linked independent
module, the terms and conditions of the license of that module. An
independent module is a module which is not derived from or based on
this library. If you modify this library, you may extend this exception
to your version of the library, but you are not obligated to do so. If
you do not wish to do so, delete this exception statement from your
version.
*/
package tuwien.auto.calimero.xml;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.Writer;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.Stack;
/**
* Default XML writer implementation of the XmlWriter interface.
*
* Does not add any feature not already documented in the implemented interface. No support for XML namespaces,
* processing instructions, DTDs, and entity refs. This writer is not thread safe.
*
* @author B. Malinowsky
*/
public class DefaultXmlWriter implements XmlWriter
{
// default indentation
private static final int indentWidth = 4;
private static final String quote = "\"";
private static final String lt = "<";
private static final String gt = ">";
private static final String equal = "=";
private static final String slash = "/";
private static final String space = " ";
private final Map config = new HashMap<>();
private final BufferedWriter w;
private final boolean close;
// xml layout stack
private final Stack layout;
// current layout indentation
private int indent;
private boolean newTag;
private boolean empty;
/**
* Creates a new XML writer with output w.
*
* The writer is buffered by this XML writer.
*
* @param w the output {@link Writer}
* @param closeWriter close w when XML writer is closed
*/
DefaultXmlWriter(final Writer w, final boolean closeWriter)
{
this.w = new BufferedWriter(w);
close = closeWriter;
layout = new Stack<>();
indent = 0;
newTag = false;
};
private void writeDeclaration(final boolean standalone, final String encoding,
final String version) throws KNXMLException
{
write(" 0)
write(" encoding=", quote, encoding, quote);
write("?>");
try {
w.newLine();
}
catch (final IOException e) {
throw new KNXMLException(e.getMessage());
}
}
@Override
public void writeComment(final String comment) throws KNXMLException
{
closeStartElement();
try {
if (newTag)
w.newLine();
indent();
write("");
if (!newTag)
w.newLine();
}
catch (final IOException e) {
throw new KNXMLException(e.getMessage(), e);
}
newTag = false;
}
@Override
public void close() throws KNXMLException
{
writeEndDocument();
try {
if (close)
w.close();
}
catch (final IOException ignore) {}
}
private BufferedWriter indent() throws IOException
{
for (int i = 0; i < indent; ++i)
w.write(' ');
return w;
}
// helper class for tag writing
private final class Tag
{
private final String name;
Tag(final String localName)
{
name = localName;
}
void addAttribute(final String localName, final String value)
{
write(space, localName, equal, quote, References.replace(value, true), quote);
}
void endTag()
{
try {
if (name != null) {
indent -= indentWidth;
if (!newTag)
indent();
newTag = false;
if (empty)
write(" ", slash, gt);
else
w.write(lt + slash + name + gt);
w.newLine();
empty = false;
}
}
catch (final IOException e) {
throw new KNXMLException("endTag", e);
}
}
}
@Override
public void writeStartElement(final String localName)
{
writeStartElement(null, localName, null);
}
@Override
public void writeStartElement(final String namespaceURI, final String localName)
{
writeStartElement(null, localName, namespaceURI);
}
@Override
public void writeStartElement(final String prefix, final String localName,
final String namespaceURI)
{
closeStartElement();
try {
if (newTag) {
w.newLine();
}
indent();
}
catch (final IOException e) {
throw new KNXMLException("write start element", e);
}
write(lt);
if (prefix != null)
write(prefix, ":");
write(localName);
newTag = true;
empty = false;
layout.push(new Tag(localName));
}
private void closeStartElement()
{
if (empty)
layout.pop().endTag();
if (newTag)
write(gt);
}
@Override
public void writeEmptyElement(final String namespaceURI, final String localName)
{
writeEmptyElement(null, localName, namespaceURI);
}
@Override
public void writeEmptyElement(final String prefix, final String localName,
final String namespaceURI)
{
writeStartElement(prefix, localName, namespaceURI);
empty = true;
}
@Override
public void writeEmptyElement(final String localName)
{
writeEmptyElement(null, localName, null);
}
@Override
public void writeEndElement()
{
closeStartElement();
if (layout.empty())
throw new IllegalStateException("no elements to end");
try {
layout.pop().endTag();
if (layout.empty())
w.flush();
}
catch (final IOException e) {
throw new KNXMLException(e.getMessage());
}
}
@Override
public void writeEndDocument()
{
try {
while (!layout.empty())
layout.pop().endTag();
w.flush();
}
catch (final IOException e) {
throw new KNXMLException(e.getMessage());
}
}
@Override
public void flush()
{
try {
w.flush();
}
catch (final IOException e) {
throw new KNXMLException("close", e);
}
}
@Override
public void writeAttribute(final String localName, final String value)
{
writeAttribute(null, null, localName, value);
}
@Override
public void writeAttribute(final String prefix, final String namespaceURI,
final String localName, final String value)
{
layout.peek().addAttribute(localName, value);
}
@Override
public void writeAttribute(final String namespaceURI, final String localName, final String value)
{
writeAttribute(null, null, localName, value);
}
@Override
public void writeNamespace(final String prefix, final String namespaceURI)
{}
@Override
public void writeDefaultNamespace(final String namespaceURI)
{}
@Override
public void writeProcessingInstruction(final String target)
{}
@Override
public void writeProcessingInstruction(final String target, final String data)
{}
@Override
public void writeCData(final String data)
{
write("");
}
@Override
public void writeDTD(final String dtd)
{}
@Override
public void writeEntityRef(final String name)
{}
@Override
public void writeStartDocument()
{
writeDeclaration(true, "utf-8", "1.0");
}
@Override
public void writeStartDocument(final String version)
{
writeDeclaration(true, "utf-8", version);
}
@Override
public void writeStartDocument(final String encoding, final String version)
{
writeDeclaration(true, encoding, version);
}
@Override
public void writeCharacters(final String text)
{
closeStartElement();
write(References.replace(text, true));
newTag = false;
}
@Override
public void writeCharacters(final char[] text, final int start, final int len)
{
final String s = new String(Arrays.copyOfRange(text, start, start + len));
writeCharacters(s);
}
@Override
public String getPrefix(final String uri)
{
return (String) config.get("prefix");
}
@Override
public void setPrefix(final String prefix, final String uri)
{
config.put("prefix", uri);
}
@Override
public void setDefaultNamespace(final String uri)
{
config.put("namespace", uri);
}
@Override
public Object getProperty(final String name) throws IllegalArgumentException
{
return config.get(name);
}
private void write(final String... items)
{
try {
for (final String s : items)
if (s != null)
w.write(s);
}
catch (final IOException e) {
throw new KNXMLException("write", e);
}
}
}