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13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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25 
26 package com.sun.xml.internal.stream;
27 
28 import java.util.NoSuchElementException;
29 import javax.xml.stream.EventFilter;
30 import javax.xml.stream.XMLEventReader;
31 import javax.xml.stream.XMLStreamException;
32 import javax.xml.stream.events.XMLEvent;
33 import javax.xml.stream.util.EventReaderDelegate;
34 
35 /**
36  *
37  * @author  Neeraj Bajaj, Sun Microsystems
38  *
39  */
40 public class EventFilterSupport extends EventReaderDelegate {
41 
42     //maintain a reference to EventFilter
43     EventFilter fEventFilter ;
44     /** Creates a new instance of EventFilterSupport */
EventFilterSupport(XMLEventReader eventReader, EventFilter eventFilter)45     public EventFilterSupport(XMLEventReader eventReader, EventFilter eventFilter) {
46         setParent(eventReader);
47         fEventFilter = eventFilter;
48     }
49 
next()50     public Object next(){
51         try{
52             return nextEvent();
53         }catch(XMLStreamException ex){
54             throw new NoSuchElementException();
55         }
56     }
57 
hasNext()58     public boolean hasNext(){
59         try{
60             return peek() != null ? true : false ;
61         }catch(XMLStreamException ex){
62             return false;
63         }
64     }
65 
nextEvent()66     public XMLEvent nextEvent()throws XMLStreamException{
67         while (super.hasNext()) {
68             //get the next event by calling XMLEventReader
69             XMLEvent event = super.nextEvent();
70 
71             //if this filter accepts this event then return this event
72             if(fEventFilter.accept(event)){
73                 return event;
74             }
75         }
76         throw new NoSuchElementException();
77     }//nextEvent()
78 
nextTag()79      public XMLEvent nextTag() throws XMLStreamException{
80          while (super.hasNext()) {
81              XMLEvent event = super.nextTag();
82              //if the filter accepts this event return this event.
83              if(fEventFilter.accept(event)){
84                 return event;
85              }
86          }
87          throw new NoSuchElementException();
88      }
89 
peek()90      public XMLEvent peek() throws XMLStreamException{
91          while (true) {
92              XMLEvent event = super.peek();
93              if(event == null)return null;
94              //if the filter accepts this event return this event.
95              if(fEventFilter.accept(event)){
96                 return event;
97              }
98              //call super.next(), and then peek again.
99              super.next();
100          }
101      }
102 
103 }//EventFilterSupport
104