/**
* David Bismut, david.bismut@gmail.com
* Intern, SETLabs, Infosys Technologies Ltd. May 2004 - Jul 2004
* Ecole des Mines de Nantes, France
*/
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import javax.accessibility.AccessibleHypertext;
import javax.swing.JEditorPane;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.Element;
import javax.swing.text.html.HTML;
import javax.swing.text.html.HTMLDocument;
import javax.swing.text.html.HTMLEditorKit;
import javax.swing.text.html.StyleSheet;
import javax.swing.text.html.parser.ParserDelegator;
/**
* A "HTML" JEditorPane embedded with a special HTMLDocument that detects urls
* and displays them as hyperlinks. When CTRL is pressed, the urls are
* clickable.
*
* @author David Bismut
*
*/
public class EditorPaneLinkDetector extends JEditorPane {
/**
* Creates a <code>EditorPaneLinkDetector</code>.
*/
public EditorPaneLinkDetector() {
HTMLEditorKit htmlkit = new HTMLEditorKit();
StyleSheet styles = htmlkit.getStyleSheet();
StyleSheet ss = new StyleSheet();
ss.addStyleSheet(styles);
ss.addRule("body {font-family:arial;font-size:12pt}");
ss.addRule("p {font-family:arial;margin:2}");
HTMLDocument doc = new HTMLDocLinkDetector(ss);
setEditorKit(htmlkit);
setDocument(doc);
addMouseMotionListener(new MouseMotionAdapter() {
public void mouseMoved(MouseEvent e) {
AccessibleJTextComponent context = (AccessibleJTextComponent) getAccessibleContext()
.getAccessibleEditableText();
AccessibleHypertext accText = (AccessibleHypertext) context
.getAccessibleText();
int index = accText.getIndexAtPoint(e.getPoint());
int linkIndex = accText.getLinkIndex(index);
if (linkIndex == -1) {
setToolTipText(null);
return;
}
String linkDesc = accText.getLink(linkIndex)
.getAccessibleActionDescription(0);
String toolTipText = "<html><body style='margin: 3'>"
+ linkDesc
+ "<br><b>CTRL + click to follow link</b></body></html>";
setToolTipText(toolTipText);
}
});
addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_CONTROL) {
if (isEditable())
setEditable(false);
} else {
if (!isEditable())
setEditable(true);
}
}
public void keyReleased(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_CONTROL) {
setEditable(true);
}
}
});
}
protected class HTMLDocLinkDetector extends HTMLDocument {
public HTMLDocLinkDetector(StyleSheet ss) {
super(ss);
setAsynchronousLoadPriority(4);
setTokenThreshold(100);
setParser(new ParserDelegator());
}
/**
* Returns true if the Element contains a HTML.Tag.A attribute, false
* otherwise.
*
* @param e
* the Element to be checkd
* @return
*/
protected boolean isLink(Element e) {
return (e.getAttributes().getAttribute(HTML.Tag.A) != null);
}
/**
* This method corrects or creates a url contained in an Element as an
* hyperlink.
*
* @param e
* the Element to be computed
* @throws BadLocationException
*/
protected void computeLinks(Element e) throws BadLocationException {
int caretPos = getCaretPosition();
try {
if (isLink(e))
correctLink(e);
else
createLink(e);
} catch (IOException ex) {
ex.printStackTrace();
}
setCaretPosition(Math.min(caretPos, getLength()));
}
/**
* The method corrects the url inside an Element, that is supposed to be
* an element containing a link only. This function is typically called
* when the url is beeing edited. What the function does is to remove
* the html tags, so the url is actually edited in plain text and not as
* an hyperlink.
*
* @param e
* the Element that contains the url
* @throws BadLocationException
* @throws IOException
*/
protected void correctLink(Element e) throws BadLocationException,
IOException {
int length = e.getEndOffset() - e.getStartOffset();
boolean endOfDoc = e.getEndOffset() == getLength() + 1;
// to avoid catching the final '\n' of the document.
if (endOfDoc)
length--;
String text = getText(e.getStartOffset(), length);
setOuterHTML(e, text);
// insert final spaces ignored by the html
Matcher spaceMatcher = Pattern.compile("(\\s+)$").matcher(text);
if (spaceMatcher.find()) {
String endingSpaces = spaceMatcher.group(1);
insertString(Math.min(getLength(), e.getEndOffset()),
endingSpaces, null);
}
}
/**
* The method check if the element contains a url in plain text, and if
* so, it creates the html tag HTML.Tag.A to have the url displayed as
* an hyperlink.
*
* @param e
* element that contains the url
* @throws BadLocationException
* @throws IOException
*/
protected void createLink(Element e) throws BadLocationException,
IOException {
int caretPos = getCaretPosition();
int startOffset = e.getStartOffset();
int length = e.getEndOffset() - e.getStartOffset();
boolean endOfDoc = e.getEndOffset() == getLength() + 1;
// to avoid catching the final '\n' of the document.
if (endOfDoc)
length--;
String text = getText(startOffset, length);
Matcher matcher = Pattern.compile(
"(?i)(\\b(http://|https://|www.|ftp://|file:/|mailto:)\\S+)(\\s+)")
.matcher(text);
if (matcher.find()) {
String url = matcher.group(1);
String prefix = matcher.group(2);
String endingSpaces = matcher.group(3);
// to ignore characters after the caret
int validPos = startOffset + matcher.start(3) + 1;
if (validPos > caretPos)
return;
Matcher dotEndMatcher = Pattern.compile("([\\W&&[^/]]+)$")
.matcher(url);
//Ending non alpha characters like [.,?%] shouldn't be included
// in the url.
String endingDots = "";
if (dotEndMatcher.find()) {
endingDots = dotEndMatcher.group(1);
url = dotEndMatcher.replaceFirst("");
}
text = matcher.replaceFirst("<a href='" + url + "'>" + url
+ "</a>" + endingDots + endingSpaces);
setOuterHTML(e, text);
// insert initial spaces ignored by the html
Matcher spaceMatcher = Pattern.compile("^(\\s+)").matcher(text);
if (spaceMatcher.find()) {
String initialSpaces = spaceMatcher.group(1);
insertString(startOffset, initialSpaces, null);
}
// insert final spaces ignored by the html
spaceMatcher = Pattern.compile("(\\s+)$").matcher(text);
if (spaceMatcher.find()) {
String extraSpaces = spaceMatcher.group(1);
int endoffset = e.getEndOffset();
if (extraSpaces.charAt(extraSpaces.length() - 1) == '\n') {
extraSpaces = extraSpaces.substring(0, extraSpaces
.length() - 1);
endoffset--;
}
insertString(Math.min(getLength(), endoffset), extraSpaces,
null);
}
}
}
public void remove(int offs, int len) throws BadLocationException {
super.remove(offs, len);
Element e = getCharacterElement(offs - len);
computeLinks(e);
}
public void insertString(int offs, String str, AttributeSet a)
throws BadLocationException {
super.insertString(offs, str, a);
Element e = getCharacterElement(offs);
computeLinks(e);
}
}
}