package info.bliki.api;
import info.bliki.htmlcleaner.util.HtmlForm;
import java.io.IOException;
import java.io.StringReader;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
/**
* TODO: delete this class file!
*
* Sources adopted from the article <a href=
* "http://www.javaworld.com/javaworld/jw-08-2008/jw-08-java-wiki-extensions.html"
* >Add Java extensions to your wiki</a> with permission from Randall Scarberry.
*
*
*/
public class HtmlUtilities {
public static final String FORM_TAG = "form";
public static final String INPUT_TAG = "input";
public static final String TEXTAREA_TAG = "textarea";
// Factory used in parseForm().
private static SAXParserFactory mParserFactory = SAXParserFactory.newInstance();
/**
* Extracts and parses an HTML form from a page of HTML.
*
* @param formID
* @param html
* @return
*/
public static HtmlForm extractForm(String formID, String html) {
String lowerCaseHtml = html.toLowerCase();
String startTag = "<" + FORM_TAG + " ";
String endTag = "</" + FORM_TAG + ">";
int ndx = lowerCaseHtml.indexOf(startTag);
while (ndx >= 0) {
int ndx2 = lowerCaseHtml.indexOf(endTag, ndx + startTag.length());
if (ndx2 > ndx) {
String formHTML = html.substring(ndx, ndx2 + endTag.length());
try {
HtmlForm form = parseForm(formID, formHTML, true);
if (form != null) {
return form;
}
} catch (IOException ioe) {
}
ndx = lowerCaseHtml.indexOf(startTag, ndx2 + endTag.length());
} else {
break;
}
}
return null;
}
public static HtmlForm parseForm(String formID, String html, boolean trapExceptions) throws IOException {
HtmlFormHandler handler = new HtmlFormHandler(formID);
try {
// screws up the parsing. What a delicate flower SAX is.
html = html.replaceAll(" ", " ");
// html = StringUtils.replace(html, " ", " ");
SAXParser parser = mParserFactory.newSAXParser();
XMLReader reader = parser.getXMLReader();
reader.setContentHandler(handler);
reader.parse(new InputSource(new StringReader(html)));
return handler.getForm();
} catch (Exception e) {
e.printStackTrace();
if (trapExceptions) {
return handler.getForm();
}
String errMsg = e.getMessage();
String ioeMsg = null;
if (errMsg != null && errMsg.length() > 0) {
ioeMsg = "invalid HTML (" + errMsg + ")";
} else {
ioeMsg = "invalid HTML";
}
throw new IOException(ioeMsg);
}
}
public static class HtmlFormHandler extends DefaultHandler {
private String mFormID;
private boolean mInForm;
private HtmlForm mForm;
private HtmlForm.Element mCurrentElement;
private StringBuffer mCurrentElementBuffer;
public HtmlFormHandler(String formID) {
if (formID == null) {
throw new NullPointerException();
}
mFormID = formID;
}
public HtmlForm getForm() {
return mForm;
}
/**
* Receive notification of the start of an element.
*
* <p>
* By default, do nothing. Application writers may override this method in a
* subclass to take specific actions at the start of each element (such as
* allocating a new tree node or writing output to a file).
* </p>
*
* @param uri
* The Namespace URI, or the empty string if the element has no
* Namespace URI or if Namespace processing is not being performed.
* @param localName
* The local name (without prefix), or the empty string if
* Namespace processing is not being performed.
* @param qName
* The qualified name (with prefix), or the empty string if
* qualified names are not available.
* @param attributes
* The attributes attached to the element. If there are no
* attributes, it shall be an empty Attributes object.
* @exception org.xml.sax.SAXException
* Any SAX exception, possibly wrapping another exception.
* @see org.xml.sax.ContentHandler#startElement
*/
@Override
public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
String elementName = localName;
if (elementName.length() == 0) {
elementName = qName;
}
if (elementName.equalsIgnoreCase("form")) {
String id = null, name = null, action = null, encType = null;
int method = HtmlForm.POST;
int sz = attributes.getLength();
for (int i = 0; i < sz; i++) {
String lname = attributes.getLocalName(i);
if (lname.length() == 0)
lname = attributes.getQName(i);
String value = attributes.getValue(i);
if (lname.equalsIgnoreCase("id")) {
if (!mFormID.equals(value)) {
// Not interested in this form.
return;
} else {
id = value;
mInForm = true;
}
} else if (lname.equalsIgnoreCase("name")) {
name = value;
} else if (lname.equalsIgnoreCase("method")) {
if ("get".equalsIgnoreCase(value)) {
method = HtmlForm.GET;
}
} else if (lname.equalsIgnoreCase("action")) {
action = value;
} else if (lname.equalsIgnoreCase("enctype")) {
encType = value;
}
} // for
if (mInForm) {
mForm = new HtmlForm(id, name, method, action, encType);
}
} else if (mInForm) { // It's an element nested within the desired form.
if (elementName.equalsIgnoreCase(INPUT_TAG) || elementName.equalsIgnoreCase(TEXTAREA_TAG)) {
int sz = attributes.getLength();
HtmlForm.ElementAttribute[] elementAttributes = new HtmlForm.ElementAttribute[sz];
for (int i = 0; i < sz; i++) {
String aname = attributes.getLocalName(i);
if (aname.length() == 0)
aname = attributes.getQName(i);
elementAttributes[i] = new HtmlForm.ElementAttribute(aname, attributes.getType(i), attributes.getValue(i));
}
mCurrentElement = new HtmlForm.Element(elementName, elementAttributes);
mForm.addElement(mCurrentElement);
}
}
}
/**
* Receive notification of the end of an element.
*
* <p>
* By default, do nothing. Application writers may override this method in a
* subclass to take specific actions at the end of each element (such as
* finalising a tree node or writing output to a file).
* </p>
*
* @param uri
* The Namespace URI, or the empty string if the element has no
* Namespace URI or if Namespace processing is not being performed.
* @param localName
* The local name (without prefix), or the empty string if
* Namespace processing is not being performed.
* @param qName
* The qualified name (with prefix), or the empty string if
* qualified names are not available.
* @exception org.xml.sax.SAXException
* Any SAX exception, possibly wrapping another exception.
* @see org.xml.sax.ContentHandler#endElement
*/
@Override
public void endElement(String uri, String localName, String qName) throws SAXException {
String elementName = localName;
if (elementName.length() == 0) {
elementName = qName;
}
if (mInForm) {
if (elementName.equalsIgnoreCase("form")) {
mInForm = false;
} else if (mCurrentElement != null && elementName.equalsIgnoreCase(mCurrentElement.getTag())) {
if (mCurrentElementBuffer != null) {
mCurrentElement.setEmbeddedText(mCurrentElementBuffer.toString());
mCurrentElementBuffer = null;
}
mCurrentElement = null;
}
}
}
/**
* Receive notification of character data inside an element.
*
* <p>
* By default, do nothing. Application writers may override this method to
* take specific actions for each chunk of character data (such as adding
* the data to a node or buffer, or printing it to a file).
* </p>
*
* @param ch
* The characters.
* @param start
* The start position in the character array.
* @param length
* The number of characters to use from the character array.
* @exception org.xml.sax.SAXException
* Any SAX exception, possibly wrapping another exception.
* @see org.xml.sax.ContentHandler#characters
*/
@Override
public void characters(char ch[], int start, int length) throws SAXException {
if (mCurrentElement != null && length > 0) {
if (mCurrentElementBuffer == null) {
mCurrentElementBuffer = new StringBuffer();
}
mCurrentElementBuffer.append(ch, start, length);
}
}
}
}