package org.freeplane.core.util;
/*
* XHTMLWriter -- A simple XHTML document writer (C) 2004 Richard "Shred"
* Koerber http://www.shredzone.net/ This is free software. You can modify and
* use it at will.
*/
import java.io.FileReader;
import java.io.FileWriter;
import java.io.FilterWriter;
import java.io.IOException;
import java.io.Reader;
import java.io.Writer;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.Element;
import javax.swing.text.StyleConstants;
import javax.swing.text.html.HTML;
import javax.swing.text.html.HTMLDocument;
import javax.swing.text.html.HTMLEditorKit;
import javax.swing.text.html.Option;
/**
* Create a new XHTMLWriter which is able to write out a HTMLDocument as XHTML.
* <p>
* The result will be a valid XML file, but it is not granted that the file will
* really be XHTML 1.0 transitional conformous. The basic purpose of this class
* is to give an XSL processor access to plain HTML files.
*
* @author Richard "Shred" Koerber
*/
class XHTMLWriter extends FixedHTMLWriter {
/**
* This FilterWriter will convert the output of Swing's HTMLWriter to XHTML
* format. This is done by converting tags like <br> to
* <br />. Also, special characters in tag attributes are
* escaped.
* <p>
* This filter relies on known flaws of the HTMLWriter. It is known to work
* with Java 1.4, but might not work with future Java releases.
*/
public static class XHTMLFilterWriter extends FilterWriter {
private boolean insideTag = false;
private boolean insideValue = false;
/**
* Create a new XHTMLFilterWriter.
*
* @param writer
* Writer to write to
*/
public XHTMLFilterWriter(final Writer writer) {
super(writer);
}
/**
* Write a char array to the Writer.
*
* @param cbuf
* Char array to be written
* @param off
* Start offset within the array
* @param len
* Number of chars to be written
*/
@Override
public void write(final char[] cbuf, int off, int len) throws IOException {
while (len-- > 0) {
write(cbuf[off++]);
}
}
/**
* Write a single char to the Writer.
*
* @param c
* Char to be written
*/
@Override
public void write(final int c) throws IOException {
if (insideValue) {
if (c == '&') {
super.write("&", 0, 5);
return;
}
else if (c == '<') {
super.write("<", 0, 4);
return;
}
else if (c == '>') {
super.write(">", 0, 4);
return;
}
else if (c == '"') {
insideValue = false;
}
}
else if (insideTag) {
if (c == '"') {
insideValue = true;
}
else if (c == '>') {
insideTag = false;
}
}
else if (c == '<') {
insideTag = true;
}
if (c > 126) {
super.write("&#x", 0, 3);
super.write(Integer.toString(c, 16));
super.write(';');
return;
}
super.write(c);
}
/**
* Write a String to the Writer.
*
* @param str
* String to be written
* @param off
* Start offset within the String
* @param len
* Number of chars to be written
*/
@Override
public void write(final String str, final int off, final int len) throws IOException {
write(str.toCharArray(), off, len);
}
}
/**
* Read HTML from the Reader, and send XHTML to the writer. Common mistakes
* in the HTML code will also be corrected. The result is pretty-printed.
*
* @param reader
* HTML source
* @param writer
* XHTML target
*/
public static void html2xhtml(final Reader reader, final Writer writer) throws IOException, BadLocationException {
final HTMLEditorKit kit = new HTMLEditorKit();
final Document doc = kit.createDefaultDocument();
kit.read(reader, doc, doc.getLength());
final XHTMLWriter xhw = new XHTMLWriter(writer, (HTMLDocument) doc);
xhw.write();
}
/**
* External call to convert a source HTML file to a target XHTML file.
* <p>
* Usage: <tt>java XHTMLWriter <source file> <target file></tt>
*
* @param args
* Shell arguments
*/
public static void main(final String[] args) {
try {
final FileReader reader = new FileReader(args[0]);
final FileWriter writer = new FileWriter(args[1]);
XHTMLWriter.html2xhtml(reader, writer);
writer.close();
reader.close();
}
catch (final Exception e) {
LogUtils.severe(e);
}
}
private boolean writeLineSeparatorEnabled = true;
private boolean insideEmptyTag;
/**
* Create a new XHTMLWriter that will write the entire HTMLDocument.
*
* @param writer
* Writer to write to
* @param doc
* Source document
*/
public XHTMLWriter(final Writer writer, final HTMLDocument doc) {
this(writer, doc, 0, doc.getLength());
}
/**
* Create a new XHTMLWriter that will write a part of a HTMLDocument.
*
* @param writer
* Writer to write to
* @param doc
* Source document
* @param pos
* Starting position
* @param len
* Length
*/
public XHTMLWriter(final Writer writer, final HTMLDocument doc, final int pos, final int len) {
super(new XHTMLFilterWriter(writer), doc, pos, len);
setLineLength(Integer.MAX_VALUE);
}
/**
* Start the writing process. An XML and DOCTYPE header will be written
* prior to the XHTML output.
*/
@Override
public void write() throws IOException, BadLocationException {
super.write();
}
@Override
protected void writeLineSeparator() throws IOException {
if (writeLineSeparatorEnabled) {
super.writeLineSeparator();
}
}
@Override
protected void writeOption(final Option option) throws IOException {
writeLineSeparatorEnabled = false;
super.writeOption(option);
writeLineSeparatorEnabled = true;
write("</option>");
writeLineSeparator();
}
/* (non-Javadoc)
* @see javax.swing.text.html.HTMLWriter#writeAttributes(javax.swing.text.AttributeSet)
*/
@Override
protected void writeAttributes(final AttributeSet attributeSet) throws IOException {
final Object nameTag = (attributeSet != null) ? attributeSet.getAttribute(StyleConstants.NameAttribute) : null;
final Object endTag = (attributeSet != null) ? attributeSet.getAttribute(HTML.Attribute.ENDTAG) : null;
// write no attributes for end tags
if (nameTag != null && endTag != null && (endTag instanceof String) && ((String) endTag).equals("true")) {
return;
}
super.writeAttributes(attributeSet);
if (insideEmptyTag) {
write('/');
}
}
// remove invalid characters
@Override
protected void output(final char[] chars, final int start, final int length) throws IOException {
for (int i = start; i < start + length; i++) {
final char c = chars[i];
if (c < 32 && c != '\r' && c != '\n' && c != '\t') {
chars[i] = ' ';
}
}
super.output(chars, start, length);
}
@Override
protected void emptyTag(final Element elem) throws BadLocationException, IOException {
try {
final boolean isEndtag = isEndtag(elem);
final int balance = balance(elem, isEndtag);
if (balance == 0 || balance > 0 && isEndtag || balance < 0 && !isEndtag) {
super.emptyTag(elem);
return;
}
if (isEndtag) {
write('<');
write(elem.getName());
write('/');
write('>');
return;
}
insideEmptyTag = true;
super.emptyTag(elem);
}
finally {
insideEmptyTag = false;
}
}
private int balance(final Element elem, final boolean isEndtag) {
final Element parentElement = elem.getParentElement();
final int elementCount = parentElement.getElementCount();
int balance = 0;
final String elemName = elem.getName();
for (int i = 0; i < elementCount; i++) {
final Element childElement = parentElement.getElement(i);
if (isEndtag) {
if (childElement.equals(elem)) {
balance--;
break;
}
}
else {
if (childElement.equals(elem)) {
balance = 1;
continue;
}
if (balance == 0) {
continue;
}
}
if (!elemName.equals(childElement.getName())) {
continue;
}
if (isEndtag(childElement)) {
if (balance > 0) {
balance--;
continue;
}
}
else {
balance++;
}
}
return balance;
}
private boolean isEndtag(final Element elem) {
final AttributeSet attributes = elem.getAttributes();
final Object endTag = attributes.getAttribute(HTML.Attribute.ENDTAG);
final boolean isEndtag = (endTag instanceof String) && ((String) endTag).equals("true");
return isEndtag;
}
@Override
protected void closeOutUnwantedEmbeddedTags(final AttributeSet attr) throws IOException {
final boolean insideEmptyTag = this.insideEmptyTag;
this.insideEmptyTag = false;
try {
super.closeOutUnwantedEmbeddedTags(attr);
}
finally {
this.insideEmptyTag = insideEmptyTag;
}
}
@Override
protected void writeEmbeddedTags(final AttributeSet attr) throws IOException {
final boolean insideEmptyTag = this.insideEmptyTag;
this.insideEmptyTag = false;
try {
super.writeEmbeddedTags(attr);
}
finally {
this.insideEmptyTag = insideEmptyTag;
}
}
}