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androidxml-parsingsimple-framework

Using simple XML in android, find a way to capture order of elements?


I've been looking for a way to capture the order of element's listed within a tag, but haven't been very successful..

EDIT NEW:

<android>
  <leags>
     <leag name = "someName">
       <headlines>
           <pageType>headlines</pageType>
           <story>someStoryURL</story>
           <fullStory>someFullStoryURL</fullStory>
       </headlines>
       <scores></scores>
       <statistics></statistics>
     </leag>
  <leags>
</android>

-Want to capture the order of elements in leag as 1)headlines 2)scores 3)statistics. If the xml changes and scores is listed before headlines it would be 1)scores 2)headlines 3)statistics.

I parse only android - Like this:

@Root(name = "android", strict = false)
public class android
{
    @ElementList(name = "leags", required = false)
    private List<Leag> leags;

        public Leag getLeagByName(String name)
        { // go through list of leags and return leag with matching name}
}

So in my "leag" object I'd want to capture the order of elements - Is there a way to do that?

I'm assuming you'd need to set new AnnotionStrategy() like this:

    tAndroid android = null;
    Serializer serial = new Persister(new AnnotationStrategy());
    android = serial.read(android .class, source);

League x= android.getLeagueByName("oeoe");
for(String s: x.getOrder())
{
    Log.i("Order", s);
}

BEFORE EDIT:

Supposing the xml above is what's being pased by the following code:

@Element(name="headlines")
public class Headlines 
{
  @Element(name="pageType", required = false)
  private String pageType;

  @Element(name="story", required = false)
  private String storiesURL;

  @Element(name="fullStory", required = false)
  private String fullStoryURL;

  public String getStoriesURL()
  {
    return storiesURL;
  }
  public String getFullStoryURL()
  {
    return fullStoryURL;
  }
  @Override
  public String toString()
  {
    return  "PageType: " + this.pageType +
            "\nStoriesURL: " + this.storiesURL + 
            "\nFullStoryURL: " + this.fullStoryURL;
  }
}

Is there a way to somehow return the order in which the elements get parsed?

Like a method that will return a string of some sort with the correct order like:

  1. pageType
  2. story
  3. fullStory

Solution

  • You can use a Converter to get the order. But you can't return the order from it (or better: you can, but better don't do it).

    It's relatively easy to get the order - the trick is getting it out from the Converter. On way is to add a list to your class and store it there.

    Implementation:

    @Root(name = "headlines")
    @Convert(value = Headlines.HeadlinesConverter.class)
    public class Headlines
    {
        @Element(name="pageType", required = false)
        private String pageType;
        @Element(name="story", required = false)
        private String storiesURL;
        @Element(name="fullStory", required = false)
        private String fullStoryURL;
    
        private List<String> order; // Here we save the order of the elements
    
    
        public String getPageType()
        {
            return pageType;
        }
    
    
        public String getStoriesURL()
        {
            return storiesURL;
        }
    
    
        public String getFullStoryURL()
        {
            return fullStoryURL;
        }
    
    
        public List<String> getOrder()
        {
            return order;
        }
    
    
    
        @Override
        public String toString()
        {
            return "Headlines{" + "pageType=" + pageType 
                    + ", storiesURL=" + storiesURL 
                    + ", fullStoryURL=" + fullStoryURL + '}';
        }
    
    
        // You can implement the converter as an extra class too
        static class HeadlinesConverter implements Converter<Headlines>
        {
            @Override
            public Headlines read(InputNode node) throws Exception
            {
                Headlines h = new Headlines();
                h.order = new ArrayList<>(3);
    
                InputNode next = node.getNext();
    
                while( next != null )
                {
                    final String value = next.getValue();
    
                    /*
                     * You can use reflection (= slower) instead the switch, or
                     * remove the switch:
                     * 
                     *     h.order.add(next.getName());
                     * 
                     * and do this after the while loop:
                     * 
                     *     h.pageType = node.getNext("pageType");
                     *     ...
                     */
                    switch(next.getName())
                    {
                        case "pageType":
                            h.pageType = value;
                            break;
                        case "story":
                            h.storiesURL = value;
                            break;
                        case "fullStory":
                            h.fullStoryURL = value;
                            break;
                        default:
                            /* Maybe some error-handling here?! */
                            break;
                    }
    
                    h.order.add(next.getName()); // add 'value' if you want the order of the values
    
                    next = node.getNext();
                }
    
                return h;
            }
    
    
            @Override
            public void write(OutputNode node, Headlines value) throws Exception
            {
                throw new UnsupportedOperationException("Not supported yet.");
            }
        }
    }
    

    Note: I didn't use setter here - but it's better you do so.

    Example code:

    final File f = new File("test.xml");
    
    Serializer ser = new Persister(new AnnotationStrategy()); /* ! */
    Headlines h = ser.read(Headlines.class, f);
    
    int i = 1;
    
    for( String s : h.getOrder() )
    {
        System.out.println((i++) + ". " + s);
    }
    

    and finally the output:

    1. pageType
    2. story
    3. fullStory