package december;
import java.io.Reader;
import java.io.StringReader;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
public class StaxBestPractice {
// switch event type + switch node name
public static void switchTypeSwitchName(Reader rdr) throws XMLStreamException {
XMLInputFactory xif = XMLInputFactory.newInstance();
XMLStreamReader xsr = xif.createXMLStreamReader(rdr);
StringBuilder sb = new StringBuilder();
while(xsr.hasNext()) {
xsr.next();
switch(xsr.getEventType()) {
case XMLStreamReader.CHARACTERS:
sb.append(xsr.getText());
break;
case XMLStreamReader.START_ELEMENT:
switch(xsr.getLocalName()) {
case "skole":
System.out.println("skole = " + xsr.getAttributeValue(null, "navn"));
break;
case "klasse":
System.out.println(" klasse = " + xsr.getAttributeValue(null, "navn"));
break;
case "elev":
System.out.println(" elev");
break;
}
sb.setLength(0);
break;
case XMLStreamReader.END_ELEMENT:
switch(xsr.getLocalName()) {
case "navn":
System.out.println(" navn = " + sb.toString());
break;
case "adresse":
System.out.println(" adresse = " + sb.toString());
break;
}
break;
}
}
xsr.close();
}
// switch event type + switch node name (with sub methods)
private static void processCharacters(XMLStreamReader xsr, StringBuilder sb) {
sb.append(xsr.getText());
}
private static void processStartElement(XMLStreamReader xsr, StringBuilder sb) {
switch(xsr.getLocalName()) {
case "skole":
System.out.println("skole = " + xsr.getAttributeValue(null, "navn"));
break;
case "klasse":
System.out.println(" klasse = " + xsr.getAttributeValue(null, "navn"));
break;
case "elev":
System.out.println(" elev");
break;
}
sb.setLength(0);
}
private static void processEndElement(XMLStreamReader xsr, StringBuilder sb) {
switch(xsr.getLocalName()) {
case "navn":
System.out.println(" navn = " + sb.toString());
break;
case "adresse":
System.out.println(" adresse = " + sb.toString());
break;
}
}
public static void switchTypeSwitchNameSub(Reader rdr) throws XMLStreamException {
XMLInputFactory xif = XMLInputFactory.newInstance();
XMLStreamReader xsr = xif.createXMLStreamReader(rdr);
StringBuilder sb = new StringBuilder();
while(xsr.hasNext()) {
xsr.next();
switch(xsr.getEventType()) {
case XMLStreamReader.CHARACTERS:
processCharacters(xsr, sb);
break;
case XMLStreamReader.START_ELEMENT:
processStartElement(xsr, sb);
break;
case XMLStreamReader.END_ELEMENT:
processEndElement(xsr, sb);
break;
}
}
xsr.close();
}
// process context based
private static boolean moveStartElement(XMLStreamReader xsr, String targetelm, String stopelm) throws XMLStreamException {
while(xsr.hasNext()) {
if(xsr.getEventType() == XMLStreamReader.START_ELEMENT && xsr.getLocalName().equals(targetelm)) {
return true;
}
if(xsr.getEventType() == XMLStreamReader.END_ELEMENT && xsr.getLocalName().equals(stopelm)) {
return false;
}
xsr.next();
}
return false;
}
private static String grabText(XMLStreamReader xsr) throws XMLStreamException {
StringBuilder sb = new StringBuilder();
while(xsr.getEventType() == XMLStreamReader.CHARACTERS) {
sb.append(xsr.getText());
xsr.next();
}
return sb.toString();
}
private static void processElev(XMLStreamReader xsr) throws XMLStreamException {
System.out.println(" elev");
if(moveStartElement(xsr, "navn", "elev")) {
xsr.next(); // move to text
System.out.println(" navn = " + grabText(xsr));
}
if(moveStartElement(xsr, "adresse", "elev")) {
xsr.next(); // move to text
System.out.println(" adresse = " + grabText(xsr));
}
}
private static void processKlasse(XMLStreamReader xsr) throws XMLStreamException {
System.out.println(" klasse = " + xsr.getAttributeValue(null, "navn"));
while(moveStartElement(xsr, "elev", "klasse")) {
processElev(xsr);
}
}
private static void processSkole(XMLStreamReader xsr) throws XMLStreamException {
System.out.println("skole = " + xsr.getAttributeValue(null, "navn"));
while(moveStartElement(xsr, "klasse", "skole")) {
processKlasse(xsr);
}
}
private static void processAlleSkoler(XMLStreamReader xsr) throws XMLStreamException {
while(moveStartElement(xsr, "skole", "alleskoler")) {
processSkole(xsr);
}
}
public static void contextBased(Reader rdr) throws XMLStreamException {
XMLInputFactory xif = XMLInputFactory.newInstance();
XMLStreamReader xsr = xif.createXMLStreamReader(rdr);
if(moveStartElement(xsr, "alleskoler", null)) {
processAlleSkoler(xsr);
}
xsr.close();
}
public static void main(String[] args) throws XMLStreamException {
String xmlstr = "<alleskoler>\r\n" +
" <skole navn='Skole X'>\r\n" +
" <klasse navn='1'>\r\n" +
" <elev id='1'>\r\n" +
" <navn>A A</navn>\r\n" +
" <adresse>A Vej 1</adresse>\r\n" +
" </elev>\r\n" +
" <elev id='2'>\r\n" +
" <navn>B B</navn>\r\n" +
" <adresse>B Vej 2</adresse>\r\n" +
" </elev>\r\n" +
" </klasse>\r\n" +
" <klasse navn='2'>\r\n" +
" <elev id='3'>\r\n" +
" <navn>C C</navn>\r\n" +
" <adresse>C Vej 3</adresse>\r\n" +
" </elev>\r\n" +
" <elev id='4'>\r\n" +
" <navn>D D</navn>\r\n" +
" <adresse>D Vej 4</adresse>\r\n" +
" </elev>\r\n" +
" </klasse>\r\n" +
" </skole>\r\n" +
" <skole navn='Skole Y'>\r\n" +
" <klasse navn='8'>\r\n" +
" <elev id='5'>\r\n" +
" <navn>E E</navn>\r\n" +
" <adresse>E Vej 5</adresse>\r\n" +
" </elev>\r\n" +
" <elev id='6'>\r\n" +
" <navn>F F</navn>\r\n" +
" <adresse>F Vej 6</adresse>\r\n" +
" </elev>\r\n" +
" </klasse>\r\n" +
" <klasse navn='9'>\r\n" +
" <elev id='7'>\r\n" +
" <navn>G G</navn>\r\n" +
" <adresse>G Vej 7</adresse>\r\n" +
" </elev>\r\n" +
" <elev id='8'>\r\n" +
" <navn>H H</navn>\r\n" +
" <adresse>H Vej 8</adresse>\r\n" +
" </elev>\r\n" +
" </klasse>\r\n" +
" </skole>\r\n" +
"</alleskoler>\r\n";
System.out.print(xmlstr);
switchTypeSwitchName(new StringReader(xmlstr));
switchTypeSwitchNameSub(new StringReader(xmlstr));
contextBased(new StringReader(xmlstr));
}
}
