如何从大型XML中获取特定元素的值

Question

我是JAVA SAX的初学者。我有一个很大的XML文件，我想从中提取一些信息。下面是我要解压的XML文件和代码：

从XML文件中提取：

    ...
    <Synset baseConcept="3" id="mizaAj_n2AR">
          <SynsetRelations>
            <SynsetRelation relType="hyponym" targets="TaboE_n2AR"/>
            <SynsetRelation relType="hyponym" targets="TaboE_n2AR"/>
            <SynsetRelation relType="hypernym" targets="ragobap_n4AR"/>
            <SynsetRelation relType="hypernym" targets="ragobap_n4AR"/>
            <SynsetRelation relType="hypernym" targets="Tiybap_Aln~afos_n1AR"/>
            <SynsetRelation relType="hypernym" targets="Tiybap_Aln~afos_n1AR"/>
          </SynsetRelations>
          <MonolingualExternalRefs>
            <MonolingualExternalRef externalReference="04623612-n" externalSystem="PWN30"/>
          </MonolingualExternalRefs>
        </Synset>
        <Synset baseConcept="3" id="ragobap_n4AR">
          <SynsetRelations>
            <SynsetRelation relType="antonym" targets="mizaAj_n2AR"/>
            <SynsetRelation relType="antonym" targets="mizaAj_n2AR"/>
          </SynsetRelations>
          <MonolingualExternalRefs>
            <MonolingualExternalRef externalReference="04624826-n" externalSystem="PWN30"/>
          </MonolingualExternalRefs>
        </Synset>
        <Synset baseConcept="3" id="tasal~uT_n1AR">
          <SynsetRelations>
            <SynsetRelation relType="has_instance" targets="simap_n1AR"/>
            <SynsetRelation relType="is_instance" targets="simap_n1AR"/>
          </SynsetRelations>
          <MonolingualExternalRefs>
            <MonolingualExternalRef externalReference="04625882-n" externalSystem="PWN30"/>
          </MonolingualExternalRefs>
        </Synset>
...

我想要：

hyponym: 2
hypernym: 4
antonym: 2 
has_instance: 1
is_instance:1

代码(主类和我的处理程序)：

    import java.io.IOException;
    import org.xml.sax.SAXException;
    import org.xml.sax.XMLReader;
    import org.xml.sax.helpers.XMLReaderFactory;

    public class Main {

        public static void main(String[] args) throws SAXException, IOException{

            XMLReader p = XMLReaderFactory.createXMLReader();
            p.setContentHandler(new handler());
            p.parse("test1.xml");
}
   ----------------------------------------
import org.xml.sax.helpers.DefaultHandler;

    public class handler extends DefaultHandler {

        @Override
        public void startElement(String SpacenameURI, String localName,
                String qName, Attributes attrs) {

            System.out.println("qname = " + qName);
            String node = qName;

            if (attrs != null) {
                for (int i = 0; i < attrs.getLength(); i++) {
                    //nous récupérons le nom de l'attribut
                    String aname = attrs.getLocalName(i);
                    //Et nous affichons sa valeur
                    System.out.println("Attribut " + aname + " valeur : " + attrs.getValue(i));
                }
            }
        }
    }