com.sun.xml.internal.stream.EventFilterSupport Maven / Gradle / Ivy

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/*
 * $Id: EventFilterSupport.java,v 1.4 2010-11-02 19:54:55 joehw Exp $
 * %W% %E%
 */
package com.sun.xml.internal.stream;

import java.util.NoSuchElementException;
import javax.xml.stream.EventFilter;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.events.XMLEvent;
import javax.xml.stream.util.EventReaderDelegate;

/**
 *
 * @author  Neeraj Bajaj, Sun Microsystems
 *
 */
public class EventFilterSupport extends EventReaderDelegate {
    
    //maintain a reference to EventFilter
    EventFilter fEventFilter ;
    /** Creates a new instance of EventFilterSupport */
    public EventFilterSupport(XMLEventReader eventReader, EventFilter eventFilter) {
        setParent(eventReader);
        fEventFilter = eventFilter;
    }
    
    public Object next(){
        try{
            return nextEvent();
        }catch(XMLStreamException ex){
            throw new NoSuchElementException();
        }
    }
    
    public boolean hasNext(){
        try{
            return peek() != null ? true : false ;
        }catch(XMLStreamException ex){
            return false;
        }
    }
    
    public XMLEvent nextEvent()throws XMLStreamException{
        if(super.hasNext()){
            //get the next event by calling XMLEventReader
            XMLEvent event = super.nextEvent();
            
            //if this filter accepts this event then return this event
            if(fEventFilter.accept(event)){
                return event;
            }
            else{
                return nextEvent();
            }
        }else{
            throw new NoSuchElementException();
        }
    }//nextEvent()
    
     public XMLEvent nextTag() throws XMLStreamException{
         if(super.hasNext()){
             XMLEvent event = super.nextTag();
             //if the filter accepts this event return this event.
             if(fEventFilter.accept(event)){
                return event;
             }
             else{
                return nextTag();
             }    
         }else{
             throw new NoSuchElementException();
         }         
     }
     
     public XMLEvent peek() throws XMLStreamException{
         while (true) {
             XMLEvent event = super.peek();
             if(event == null)return null;
             //if the filter accepts this event return this event.
             if(fEventFilter.accept(event)){
                return event;
             }
             //call super.next(), and then peek again.
             super.next();
         }
     }
     
}//EventFilterSupport