com.sun.tools.xjc.util.SubtreeCutter Maven / Gradle / Ivy
The newest version!
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 1997-2007 Sun Microsystems, Inc. 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.html
* or glassfish/bootstrap/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 glassfish/bootstrap/legal/LICENSE.txt.
* Sun designates this particular file as subject to the "Classpath" exception
* as provided by Sun in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the License
* Header, with the fields enclosed by brackets [] replaced by your own
* identifying information: "Portions Copyrighted [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.tools.xjc.util;
import org.xml.sax.helpers.XMLFilterImpl;
import org.xml.sax.helpers.DefaultHandler;
import org.xml.sax.XMLFilter;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import org.xml.sax.Attributes;
/**
* {@link XMLFilter} that can cut sub-trees.
*
* @author Kohsuke Kawaguchi
*/
public abstract class SubtreeCutter extends XMLFilterImpl {
/**
* When we are pruning a sub tree, this field holds the depth of
* elements that are being cut. Used to resume event forwarding.
*
* As long as this value is 0, we will pass through data.
*/
private int cutDepth=0;
/**
* This object will receive SAX events while a sub tree is being
* pruned.
*/
private static final ContentHandler stub = new DefaultHandler();
/**
* This field remembers the user-specified ContentHandler.
* So that we can restore it once the sub tree is completely pruned.
*/
private ContentHandler next;
public void startDocument() throws SAXException {
cutDepth=0;
super.startDocument();
}
public boolean isCutting() {
return cutDepth>0;
}
/**
* Starts cutting a sub-tree. Should be called from within the
* {@link #startElement(String, String, String, Attributes)} implementation
* before the execution is passed to {@link SubtreeCutter#startElement(String, String, String, Attributes)} .
* The current element will be cut.
*/
public void startCutting() {
super.setContentHandler(stub);
cutDepth=1;
}
public void setContentHandler(ContentHandler handler) {
next = handler;
// changes take effect immediately unless the sub-tree is being pruned
if(getContentHandler()!=stub)
super.setContentHandler(handler);
}
public void startElement(String uri, String localName, String qName, Attributes atts) throws SAXException {
if(cutDepth>0)
cutDepth++;
super.startElement(uri, localName, qName, atts);
}
public void endElement(String namespaceURI, String localName, String qName) throws SAXException {
super.endElement(namespaceURI, localName, qName);
if( cutDepth!=0 ) {
cutDepth--;
if( cutDepth == 1 ) {
// pruning completed. restore the user handler
super.setContentHandler(next);
cutDepth=0;
}
}
}
}