com.sun.xml.xsom.impl.parser.state.NGCCRuntime Maven / Gradle / Ivy
/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. * * Copyright (c) 1997-2011 Oracle and/or its affiliates. All rights reserved. * * The contents of this file are subject to the terms of either the GNU * General Public License Version 2 only ("GPL") or the Common Development * and Distribution License("CDDL") (collectively, the "License"). You * may not use this file except in compliance with the License. You can * obtain a copy of the License at * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html * or packager/legal/LICENSE.txt. See the License for the specific * language governing permissions and limitations under the License. * * When distributing the software, include this License Header Notice in each * file and include the License file at packager/legal/LICENSE.txt. * * GPL Classpath Exception: * Oracle designates this particular file as subject to the "Classpath" * exception as provided by Oracle in the GPL Version 2 section of the License * file that accompanied this code. * * Modifications: * If applicable, add the following below the License Header, with the fields * enclosed by brackets [] replaced by your own identifying information: * "Portions Copyright [year] [name of copyright owner]" * * Contributor(s): * If you wish your version of this file to be governed by only the CDDL or * only the GPL Version 2, indicate your decision by adding "[Contributor] * elects to include this software in this distribution under the [CDDL or GPL * Version 2] license." If you don't indicate a single choice of license, a * recipient has the option to distribute your version of this file under * either the CDDL, the GPL Version 2 or to extend the choice of license to * its licensees as provided above. However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. */ package com.sun.xml.xsom.impl.parser.state; import java.text.MessageFormat; import java.util.ArrayList; import java.util.Stack; import java.util.StringTokenizer; import org.xml.sax.Attributes; import org.xml.sax.ContentHandler; import org.xml.sax.Locator; import org.xml.sax.SAXException; import org.xml.sax.SAXParseException; /** * Runtime Engine for RELAXNGCC execution. * * This class has the following functionalities: * *
. **
- Managing a stack of NGCCHandler objects and * switching between them appropriately. * *
- Keep track of all Attributes. * *
- manage mapping between namespace URIs and prefixes. * *
- TODO: provide support for interleaving. * * @version $Id: NGCCRuntime.java,v 1.15 2002/09/29 02:55:48 okajima Exp $ * @author Kohsuke Kawaguchi ([email protected]) */ public class NGCCRuntime implements ContentHandler, NGCCEventSource { public NGCCRuntime() { reset(); } /** * Sets the root handler, which will be used to parse the * root element. *
* This method can be called right after the object is created * or the reset method is called. You can't replace the root * handler while parsing is in progress. *
* Usually a generated class that corresponds to the <start> * pattern will be used as the root handler, but any NGCCHandler * can be a root handler. * * @exception IllegalStateException * If this method is called but it doesn't satisfy the * pre-condition stated above. */ public void setRootHandler( NGCCHandler rootHandler ) { if(currentHandler!=null) throw new IllegalStateException(); currentHandler = rootHandler; } /** * Cleans up all the data structure so that the object can be reused later. * Normally, applications do not need to call this method directly, * * as the runtime resets itself after the endDocument method. */ public void reset() { attStack.clear(); currentAtts = null; currentHandler = null; indent=0; locator = null; namespaces.clear(); needIndent = true; redirect = null; redirectionDepth = 0; text = new StringBuffer(); // add a dummy attributes at the bottom as a "centinel." attStack.push(new AttributesImpl()); } // current content handler can be acccessed via set/getContentHandler. private Locator locator; public void setDocumentLocator( Locator _loc ) { this.locator=_loc; } /** * Gets the source location of the current event. * *
* One can call this method from RelaxNGCC handlers to access * the line number information. Note that to */ public Locator getLocator() { return locator; } /** stack of {@link Attributes}. */ private final Stack attStack = new Stack(); /** current attributes set. always equal to attStack.peek() */ private AttributesImpl currentAtts; /** * Attributes that belong to the current element. *
* It's generally not recommended for applications to use * this method. RelaxNGCC internally removes processed attributes, * so this doesn't correctly reflect all the attributes an element * carries. */ public Attributes getCurrentAttributes() { return currentAtts; } /** accumulated text. */ private StringBuffer text = new StringBuffer(); /** The current NGCCHandler. Always equals to handlerStack.peek() */ private NGCCEventReceiver currentHandler; public int replace( NGCCEventReceiver o, NGCCEventReceiver n ) { if(o!=currentHandler) throw new IllegalStateException(); // bug of RelaxNGCC currentHandler = n; return 0; // we only have one thread. } /** * Processes buffered text. * * This method will be called by the start/endElement event to process * buffered text as a text event. * *
* Whitespace handling is a tricky business. Consider the following * schema fragment: * *
* * * Assume we hit the following instance: ** ** ** * * * * Then this first space needs to be ignored (for otherwise, we will * end up treating this space as the match to <text/> and won't * be able to process <bar>.) * * Now assume the following instance: ** * * * This time, we need to treat this empty string as a text, for * otherwise we won't be able to accept this instance. * ** * This is very difficult to solve in general, but one seemingly * easy solution is to use the type of next event. If a text is * followed by a start tag, it follows from the constraint on * RELAX NG that that text must be either whitespaces or a match * to <text/>. * *
* On the contrary, if a text is followed by a end tag, then it * cannot be whitespace unless the content model can accept empty, * in which case sending a text event will be harmlessly ignored * by the NGCCHandler. * *
* Thus this method take one parameter, which controls the * behavior of this method. * *
* TODO: according to the constraint of RELAX NG, if characters * follow an end tag, then they must be either whitespaces or * must match to <text/>. * * @param possiblyWhitespace * True if the buffered character can be ignorabale. False if * it needs to be consumed. */ private void processPendingText(boolean ignorable) throws SAXException { if(ignorable && text.toString().trim().length()==0) ; // ignore. See the above javadoc comment for the description else currentHandler.text(text.toString()); // otherwise consume this token // truncate StringBuffer, but avoid excessive allocation. if(text.length()>1024) text = new StringBuffer(); else text.setLength(0); } public void processList( String str ) throws SAXException { StringTokenizer t = new StringTokenizer(str, " \t\r\n"); while(t.hasMoreTokens()) currentHandler.text(t.nextToken()); } public void startElement(String uri, String localname, String qname, Attributes atts) throws SAXException { if(redirect!=null) { redirect.startElement(uri,localname,qname,atts); redirectionDepth++; } else { processPendingText(true); // System.out.println("startElement:"+localname+"->"+_attrStack.size()); currentHandler.enterElement(uri, localname, qname, atts); } } /** * Called by the generated handler code when an enter element * event is consumed. * *
* Pushes a new attribute set. * *
* Note that attributes are NOT pushed at the startElement method, * because the processing of the enterElement event can trigger * other attribute events and etc. *
* This method will be called from one of handlers when it truely * consumes the enterElement event. */ public void onEnterElementConsumed( String uri, String localName, String qname,Attributes atts) throws SAXException { attStack.push(currentAtts=new AttributesImpl(atts)); nsEffectiveStack.push( new Integer(nsEffectivePtr) ); nsEffectivePtr = namespaces.size(); } public void onLeaveElementConsumed(String uri, String localName, String qname) throws SAXException { attStack.pop(); if(attStack.isEmpty()) currentAtts = null; else currentAtts = (AttributesImpl)attStack.peek(); nsEffectivePtr = ((Integer)nsEffectiveStack.pop()).intValue(); } public void endElement(String uri, String localname, String qname) throws SAXException { if(redirect!=null) { redirect.endElement(uri,localname,qname); redirectionDepth--; if(redirectionDepth!=0) return; // finished redirection. for( int i=0; i
// // // // With this grammar, when the endElement event is consumed, two handlers // are on the stack (because a child object won't revert to its parent // unless it sees a next event.) // pass around an "impossible" token. currentHandler.leaveElement(IMPOSSIBLE,IMPOSSIBLE,IMPOSSIBLE); reset(); } public void startDocument() {} // // // event dispatching methods // // public void sendEnterAttribute( int threadId, String uri, String local, String qname) throws SAXException { currentHandler.enterAttribute(uri,local,qname); } public void sendEnterElement( int threadId, String uri, String local, String qname, Attributes atts) throws SAXException { currentHandler.enterElement(uri,local,qname,atts); } public void sendLeaveAttribute( int threadId, String uri, String local, String qname) throws SAXException { currentHandler.leaveAttribute(uri,local,qname); } public void sendLeaveElement( int threadId, String uri, String local, String qname) throws SAXException { currentHandler.leaveElement(uri,local,qname); } public void sendText(int threadId, String value) throws SAXException { currentHandler.text(value); } // // // redirection of SAX2 events. // // /** When redirecting a sub-tree, this value will be non-null. */ private ContentHandler redirect = null; /** * Counts the depth of the elements when we are re-directing * a sub-tree to another ContentHandler. */ private int redirectionDepth = 0; /** * This method can be called only from the enterElement handler. * The sub-tree rooted at the new element will be redirected * to the specified ContentHandler. * *// * Currently active NGCCHandler will only receive the leaveElement * event of the newly started element. * * @param uri,local,qname * Parameters passed to the enter element event. Used to * simulate the startElement event for the new ContentHandler. */ public void redirectSubtree( ContentHandler child, String uri, String local, String qname ) throws SAXException { redirect = child; redirect.setDocumentLocator(locator); redirect.startDocument(); // TODO: when a prefix is re-bound to something else, // the following code is potentially dangerous. It should be // modified to report active bindings only. for( int i=0; i
namespaces.size() * For example, consider the following schema: *
* Code fragment X is executed after we see a startElement event, * but at this time the namespaces variable already include new * namespace bindings declared on "bob". */ private int nsEffectivePtr=0; /** * Stack to preserve old nsEffectivePtr values. */ private final Stack nsEffectiveStack = new Stack(); public String resolveNamespacePrefix( String prefix ) { for( int i = nsEffectivePtr-2; i>=0; i-=2 ) if( namespaces.get(i).equals(prefix) ) return (String)namespaces.get(i+1); // no binding was found. if(prefix.equals("")) return ""; // return the default no-namespace if(prefix.equals("xml")) // pre-defined xml prefix return "http://www.w3.org/XML/1998/namespace"; else return null; // prefix undefined } // error reporting protected void unexpectedX(String token) throws SAXException { throw new SAXParseException(MessageFormat.format( "Unexpected {0} appears at line {1} column {2}", new Object[]{ token, new Integer(getLocator().getLineNumber()), new Integer(getLocator().getColumnNumber()) }), getLocator()); } // // // trace functions // // private int indent=0; private boolean needIndent=true; private void printIndent() { for( int i=0; i* * * code fragment X ** *