4.6 Access to Attributes

[next] [prev] [prev-tail] [tail] [up]

4.6 Access to Attributes

public static void main(String[] args) throws Exception {
   ....
   xmlReader.setContentHandler( new MyContentHandler( ... ) );
   ....
}
class MyContentHandler extends DefaultHandler {
  public void startDocument(){ ... }
  public void endDocument(){ ... }
  public void startElement(String ns, String sname,
                     String qName, Attributes atts) { ... }
  public void endElement(String ns,
                        String sname, String qName) { ... }
  public void characters(char[] ch, int start, int length){ ... }
}

The Attributes interface shows how attributes of elements may be accessed.

String getValue(String name)
String getQName(int index)
String getValue(int index)
int getLength()

<..a handler accessing SAX attributes ..>

class MyContentHandler extends DefaultHandler {
      String curColor, titleColor, background;
      int y;

   public void startElement(String ns, String sname,
                           String qName, Attributes atts) {
      if( qName.equals("document") ){
         if( atts.getLength() != 2 ){ System.err.println("ERROR"); }
         if( !atts.getQName(0).equals("title") ){
                                         System.err.println("ERROR"); }
         titleColor = atts.getValue(0);
         background = atts.getValue( "canvas" );
      }
      curColor = qName.equals("title")? titleColor : "black";
   }

   public void characters(char[] ch, int start, int length){
     <.insert colored text and background at distance y .>
   }

   public void startDocument(){ <.insert svg header .> }

   public void endDocument(){ System.out.println( "</svg>" );
   }
}

-_-_-

<?xml version="1.0" encoding="UTF-8"?>
<document title="red" canvas="yellow">
  <section>
    <title>First section</title>
    <sentence>Some text.</sentence>
    <sentence>More text.</sentence>
  </section>
  <section>
    <title>Second section</title>
    <sentence>Another text.</sentence>
    <sentence>Yet more text.</sentence>
  </section>
</document>

  <rect x="0" y="0" width="100%"
    height="15" fill="yellow"/>
  <text x="10" y="15"
    stroke="red">First section</text>
  <rect x="0" y="15" width="100%"
    height="15" fill="yellow"/>
  <text x="10" y="30"
    stroke="black">Some text.</text>

Note the wasteful approach used for painting the background!

[next] [prev] [prev-tail] [front] [up]