| package org.apache.maven.model.transform; |
| |
| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| import java.util.ArrayDeque; |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.Queue; |
| |
| import org.apache.maven.model.transform.sax.AbstractSAXFilter; |
| import org.apache.maven.model.transform.sax.SAXEvent; |
| import org.apache.maven.model.transform.sax.SAXEventFactory; |
| import org.xml.sax.Attributes; |
| import org.xml.sax.Locator; |
| import org.xml.sax.SAXException; |
| |
| /** |
| * Builds up a list of SAXEvents, which will be executed with {@link #executeEvents()} |
| * |
| * @author Robert Scholte |
| * @since 4.0.0 |
| */ |
| abstract class AbstractEventXMLFilter extends AbstractSAXFilter |
| { |
| private Queue<SAXEvent> saxEvents = new ArrayDeque<>(); |
| |
| private SAXEventFactory eventFactory; |
| |
| // characters BEFORE startElement must get state of startingElement |
| // this way removing based on state keeps correct formatting |
| private List<SAXEvent> charactersSegments = new ArrayList<>(); |
| |
| private boolean lockCharacters = false; |
| |
| protected abstract boolean isParsing(); |
| |
| protected abstract String getState(); |
| |
| protected boolean acceptEvent( String state ) |
| { |
| return true; |
| } |
| |
| AbstractEventXMLFilter() |
| { |
| super(); |
| } |
| |
| AbstractEventXMLFilter( AbstractSAXFilter parent ) |
| { |
| super( parent ); |
| } |
| |
| private SAXEventFactory getEventFactory() |
| { |
| if ( eventFactory == null ) |
| { |
| eventFactory = SAXEventFactory.newInstance( getContentHandler(), getLexicalHandler() ); |
| } |
| return eventFactory; |
| } |
| |
| private void processEvent( final SAXEvent event ) |
| throws SAXException |
| { |
| if ( isParsing() ) |
| { |
| final String eventState = getState(); |
| |
| if ( !lockCharacters ) |
| { |
| charactersSegments.forEach( e -> |
| saxEvents.add( () -> |
| { |
| if ( acceptEvent( eventState ) ) |
| { |
| e.execute(); |
| } |
| } ) ); |
| charactersSegments.clear(); |
| } |
| |
| saxEvents.add( () -> |
| { |
| if ( acceptEvent( eventState ) ) |
| { |
| event.execute(); |
| } |
| } ); |
| } |
| else |
| { |
| event.execute(); |
| } |
| } |
| |
| /** |
| * Should be used to include extra events before a closing element. |
| * This is a lightweight solution to keep the correct indentation. |
| */ |
| protected Includer include() |
| { |
| this.lockCharacters = true; |
| |
| return () -> lockCharacters = false; |
| } |
| |
| protected final void executeEvents() throws SAXException |
| { |
| final String eventState = getState(); |
| charactersSegments.forEach( e -> |
| saxEvents.add( () -> |
| { |
| if ( acceptEvent( eventState ) ) |
| { |
| e.execute(); |
| } |
| } ) ); |
| charactersSegments.clear(); |
| |
| // not with streams due to checked SAXException |
| while ( !saxEvents.isEmpty() ) |
| { |
| saxEvents.poll().execute(); |
| } |
| } |
| |
| @Override |
| public void setDocumentLocator( Locator locator ) |
| { |
| try |
| { |
| processEvent( getEventFactory().setDocumentLocator( locator ) ); |
| } |
| catch ( SAXException e ) |
| { |
| // noop, setDocumentLocator can never throw a SAXException |
| } |
| } |
| |
| @Override |
| public void startDocument() throws SAXException |
| { |
| processEvent( getEventFactory().startDocument() ); |
| } |
| |
| @Override |
| public void endDocument() throws SAXException |
| { |
| processEvent( getEventFactory().endDocument() ); |
| } |
| |
| @Override |
| public void startPrefixMapping( String prefix, String uri ) throws SAXException |
| { |
| processEvent( getEventFactory().startPrefixMapping( prefix, uri ) ); |
| } |
| |
| @Override |
| public void endPrefixMapping( String prefix ) throws SAXException |
| { |
| processEvent( getEventFactory().endPrefixMapping( prefix ) ); |
| } |
| |
| @Override |
| public void startElement( String uri, String localName, String qName, Attributes atts ) throws SAXException |
| { |
| processEvent( getEventFactory().startElement( uri, localName, qName, atts ) ); |
| } |
| |
| @Override |
| public void endElement( String uri, String localName, String qName ) throws SAXException |
| { |
| processEvent( getEventFactory().endElement( uri, localName, qName ) ); |
| } |
| |
| @Override |
| public void characters( char[] ch, int start, int length ) throws SAXException |
| { |
| if ( lockCharacters ) |
| { |
| processEvent( getEventFactory().characters( ch, start, length ) ); |
| } |
| else if ( isParsing() ) |
| { |
| this.charactersSegments.add( getEventFactory().characters( ch, start, length ) ); |
| } |
| else |
| { |
| super.characters( ch, start, length ); |
| } |
| } |
| |
| @Override |
| public void ignorableWhitespace( char[] ch, int start, int length ) throws SAXException |
| { |
| processEvent( getEventFactory().ignorableWhitespace( ch, start, length ) ); |
| } |
| |
| @Override |
| public void processingInstruction( String target, String data ) throws SAXException |
| { |
| processEvent( getEventFactory().processingInstruction( target, data ) ); |
| } |
| |
| @Override |
| public void skippedEntity( String name ) throws SAXException |
| { |
| processEvent( getEventFactory().skippedEntity( name ) ); |
| } |
| |
| @Override |
| public void startDTD( String name, String publicId, String systemId ) throws SAXException |
| { |
| processEvent( getEventFactory().startCDATA() ); |
| } |
| |
| @Override |
| public void endDTD() throws SAXException |
| { |
| processEvent( getEventFactory().endDTD() ); |
| } |
| |
| @Override |
| public void startEntity( String name ) throws SAXException |
| { |
| processEvent( getEventFactory().startEntity( name ) ); |
| } |
| |
| @Override |
| public void endEntity( String name ) throws SAXException |
| { |
| processEvent( getEventFactory().endEntity( name ) ); |
| } |
| |
| @Override |
| public void startCDATA() |
| throws SAXException |
| { |
| processEvent( getEventFactory().startCDATA() ); |
| } |
| |
| @Override |
| public void endCDATA() |
| throws SAXException |
| { |
| processEvent( getEventFactory().endCDATA() ); |
| } |
| |
| @Override |
| public void comment( char[] ch, int start, int length ) |
| throws SAXException |
| { |
| processEvent( getEventFactory().comment( ch, start, length ) ); |
| } |
| |
| /** |
| * AutoCloseable with a close method that doesn't throw an exception |
| * |
| * @author Robert Scholte |
| * |
| */ |
| @FunctionalInterface |
| protected interface Includer extends AutoCloseable |
| { |
| void close(); |
| } |
| } |