Locating Specific Attributes in Digester - Java

Question

I'm using the Apache Commons Digester and trying to locate a particular tag in the structure to include in the object.

<parent>

<image size="small">some url</image>

<image size="medium">some url</image>

<image size="large">some url</image>

<image size="huge">some url</image>

</parent>

I really only want the medium image to be included in my partent object but I'm not sure how I would do that.

Right now I'm using digester.addBeanPropertySetter(PathToParent+"/image","image"); but this gets updated for every image tag (as it should).

Ideally I would like something like digester.addBeanPropertySetter(PathToParent+"/image/medium","image"); but you can't do that.

Answer 1

I omitted generic getters/setters.

  public class Parent {

    private Image image;

    public void setImage(Image image) {
      if ("medium".equals(image.getSize())) {
        this.image = image;
      }
    }

  }

  public class Image {

    private String size;
    private String url;
  }

  public static void main(String[] args) throws IOException, SAXException {
    String s = "<parent>" 
        + "<image size='small'>some url1</image>"
        + "<image size='medium'>some url2</image>"
        + "<image size='large'>some url3</image>"
        + "<image size='huge'>some url4</image>"
        + "</parent>";

    Digester digester = new Digester();

    digester.addObjectCreate("parent", Parent.class);
    digester.addFactoryCreate("parent/image", new ImageCreationFactory());
    digester.addBeanPropertySetter("parent/image", "url");
    digester.addSetNext("parent/image", "setImage");
    Parent p = (Parent) digester.parse(new StringReader(s));
  }

  public class ImageCreationFactory implements ObjectCreationFactory {

    public Object createObject(Attributes attributes) throws Exception {
      Image i = new Image();
      i.setSize(attributes.getValue("size"));
      return i;
    }

  }