* This is a SAX filter which resolves all XInclude include elements * before passing them on to the client application. Currently this * class has the following known deviation from the XInclude specification: *
*
* Extensions made by JP and TP:
* the URL of the included TEXT document (i.e. if parse='text')
* can be in one of the following forms (lines are numbered starting at 1):
*
*
textfileurl#startLineNumber will include only the line with startLineNumbertextfileurl#startLineNumber$count will include count lines beginning from startLineNumbertextfileurl#startLineNumber-endLineNumber will include all lines
beginning from startLineNumber and ending to (including) line endLineNumbertextfileurl#startLineNumber- will include all lines
beginning from to the end of filetextfileurl#$countOfLines or textfileurl#-countOfLines will include first countOfLines lines
from the file* Furthermore, I would definitely use a new instance of this class * for each document you want to process. I doubt it can be used * successfully on multiple documents. Furthermore, I can virtually * guarantee that this class is not thread safe. You have been * warned. *
* ** Since this class is not designed to be subclassed, and since * I have not yet considered how that might affect the methods * herein or what other protected methods might be needed to support * subclasses, I have declared this class final. I may remove this * restriction later, though the use-case for subclassing is weak. * This class is designed to have its functionality extended via a * a horizontal chain of filters, not a * vertical hierarchy of sub and superclasses. *
* ** To use this class: *
*XIncludeFilter object with a known base URLXMLReader object from which the raw document will
* be read to the setParent() method of this object. ContentHandler object to the
* setContentHandler() method of this object. This is the
* object which will receive events from the parsed and included
* document.
* LexicalHandler object as the value of this object's
* http://xml.org/sax/properties/lexical-handler property.
* Also make sure your LexicalHandler asks this object
* for the status of each comment using insideIncludeElement
* before doing anything with the comment.
* parse() methode.g.
*XIncludeFilter includer = new XIncludeFilter(base);
* includer.setParent(parser);
* includer.setContentHandler(new SAXXIncluder(System.out));
* includer.parse(args[i]);
* term1 String
*/
protected static final String term1 = "#";
/**
* the number of lines to be included
* is specified in the URL after the term2 String
*/
protected static final String term2 = "$";
/**
* the number of the last line to be included
* is specified in the URL after the term3 String
*/
protected static final String term3 = "-";
public final static String XINCLUDE_NAMESPACE
= "http://www.w3.org/2001/XInclude";
private Stack bases = new Stack();
private Stack locators = new Stack();
/* private EntityResolver resolver;
public XIncludeFilter() {
this(null);
}
public XIncludeFilter(EntityResolver resolver) {
this.resolver = resolver;
} */
// what if this isn't called????
// do I need to check this in startDocument() and push something
// there????
public void setDocumentLocator(Locator locator) {
locators.push(locator);
String base = locator.getSystemId();
try {
bases.push(new URL(base));
}
catch (MalformedURLException e) {
throw new UnsupportedOperationException("Unrecognized SYSTEM ID: " + base);
}
super.setDocumentLocator(locator);
}
// necessary to throw away contents of non-empty XInclude elements
private int level = 0;
/**
* * This utility method returns true if and only if this reader is * currently inside a non-empty include element. (This is * not the same as being inside the node set which replaces * the include element.) This is primarily needed for comments * inside include elements. It must be checked by the actual * LexicalHandler to see whether a comment is passed or not. *
* * @return boolean */ public boolean insideIncludeElement() { return level != 0; } public void startElement(String uri, String localName, String qName, Attributes atts) throws SAXException { if (level == 0) { // We're not inside an xi:include element // Adjust bases stack by pushing either the new // value of xml:base or the base of the parent String base = atts.getValue(NamespaceSupport.XMLNS, "base"); URL parentBase = (URL) bases.peek(); URL currentBase = parentBase; if (base != null) { try { currentBase = new URL(parentBase, base); } catch (MalformedURLException e) { throw new SAXException("Malformed base URL: " + currentBase, e); } } bases.push(currentBase); if (uri.equals(XINCLUDE_NAMESPACE) && localName.equals("include")) { // include external document String href = atts.getValue("href"); // Verify that there is an href attribute if (href==null) { throw new SAXException("Missing href attribute"); } String parse = atts.getValue("parse"); if (parse == null) parse = "xml"; if (parse.equals("text")) { String encoding = atts.getValue("encoding"); includeTextDocument(href, encoding); } else if (parse.equals("xml")) { includeXMLDocument(href); } // Need to check this also in DOM and JDOM???? else { throw new SAXException( "Illegal value for parse attribute: " + parse); } level++; } else { if (atRoot) { // add xml:base attribute if necessary AttributesImpl attsImpl = new AttributesImpl(atts); attsImpl.addAttribute(NamespaceSupport.XMLNS, "base", "xml:base", "CDATA", currentBase.toExternalForm()); atts = attsImpl; atRoot = false; } super.startElement(uri, localName, qName, atts); } } } public void endElement (String uri, String localName, String qName) throws SAXException { if (uri.equals(XINCLUDE_NAMESPACE) && localName.equals("include")) { level--; } else if (level == 0) { bases.pop(); super.endElement(uri, localName, qName); } } private int depth = 0; public void startDocument() throws SAXException { level = 0; if (depth == 0) super.startDocument(); depth++; } public void endDocument() throws SAXException { locators.pop(); bases.pop(); // pop the URL for the document itself depth--; if (depth == 0) super.endDocument(); } // how do prefix mappings move across documents???? public void startPrefixMapping(String prefix, String uri) throws SAXException { if (level == 0) super.startPrefixMapping(prefix, uri); } public void endPrefixMapping(String prefix) throws SAXException { if (level == 0) super.endPrefixMapping(prefix); } public void characters(char[] ch, int start, int length) throws SAXException { if (level == 0) super.characters(ch, start, length); } public void ignorableWhitespace(char[] ch, int start, int length) throws SAXException { if (level == 0) super.ignorableWhitespace(ch, start, length); } public void processingInstruction(String target, String data) throws SAXException { if (level == 0) super.processingInstruction(target, data); } public void skippedEntity(String name) throws SAXException { if (level == 0) super.skippedEntity(name); } // convenience method for error messages private String getLocation() { String locationString = ""; Locator locator = (Locator) locators.peek(); String publicID = ""; String systemID = ""; int column = -1; int line = -1; if (locator != null) { publicID = locator.getPublicId(); systemID = locator.getSystemId(); line = locator.getLineNumber(); column = locator.getColumnNumber(); } locationString = " in document included from " + publicID + " at " + systemID + " at line " + line + ", column " + column; return locationString; } /** ** This method reads URL and return the first line to read *
* * @param url URL of the document that will be read * @return int * * @author Jan Pavlovic, Tomas Pitner * @version May 2003 */ protected int getLineBegin(String url) { int indexTerm1 = url.indexOf(term1) + 1; // position after # if (indexTerm1 == 0) { // if no # return 0 return 0; } int separatorIndex = url.indexOf(term2); // from # until $ if (separatorIndex < 0) separatorIndex = url.indexOf(term3); // from # until - if (separatorIndex < 0) separatorIndex = url.length(); // take whole URL if (indexTerm1 == separatorIndex) { // if #$ or #- return 1 return 1; } String begin = url.substring(indexTerm1, separatorIndex).trim(); try { // System.err.println("line-begin: parsing begin='"+begin+"'"); return Integer.parseInt(begin); } catch (NumberFormatException nfe) { return 0; } } /** ** This method reads URL and return the amount of line line to read *
* * @param url URL of the document that will be read * @return int * * @author Jan Pavlovic, Tomas Pitner * @version May 2003 */ protected int getLineCount(String url) { if (url.indexOf(term1) == -1) { return Integer.MAX_VALUE; } int indexTerm2 = url.indexOf(term2)+1; int indexTerm3 = url.indexOf(term3)+1; //System.err.println("line-count: indexTerm2="+indexTerm2+", indexTerm3="+indexTerm3+", url.length="+url.length()); // if no $ neither - then include one line: if (indexTerm2 == 0 && indexTerm3 == 0) { return 1; } // if - at the end of the url then include all lines to the end: if (indexTerm3 == url.length()) { return Integer.MAX_VALUE; } String count = url.substring(indexTerm2).trim(); // from $ to end String last = url.substring(indexTerm3).trim(); // from - to end try { // if '$' (count of lines) specified if (indexTerm2 > 0) { // System.err.println("line-count: parsing count='"+count+"'"); int iCount = Integer.parseInt(count); return iCount; // if '-' (last line number) specified } else { // System.err.println("line-count: parsing last='"+last+"'"); int iLast = Integer.parseInt(last); return iLast + 1 - getLineBegin(url); } } catch (NumberFormatException nfe) { return 0; } } /** *
* This utility method reads a document at a specified URL
* and fires off calls to characters().
* It's used to include files with parse="text"
*
* This utility method reads a document at a specified URL
* and fires off calls to various ContentHandler methods.
* It's used to include files with parse="xml"
*