XML
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package name.panitz.xml;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.io.*;
import org.w3c.dom.*;
import javax.xml.parsers.*;
import org.xml.sax.*;
import org.xml.sax.helpers.*;
import javax.xml.stream.*;
import javax.xml.stream.events.*;
import javax.xml.xpath.*;
import javax.xml.transform.*;
import javax.xml.transform.stream.*;
public interface XML{
XML setParent(XML parent);
XML parentNode();
public static record Text(String text,XML parentNode) implements XML{
public XML setParent(XML parent){return new Text(text,parent);}
@Override public String toString(){
return "Text["+text+"]";
}
}
public static record
Element(String name,List<XML> childNodes,Map<String,String> attributes,XML parentNode)
implements XML{
public XML setParent(XML parent){
var newChildNodes = new ArrayList<XML>();
var r = new Element(name,newChildNodes,attributes,parent);
for (var cn:childNodes) newChildNodes.add(cn.setParent(r));
return r;
}
@Override public String toString(){
return "Element["+name+","+childNodes+","+attributes+"]";
}
}
default int count(){
if (this instanceof Text t) return 1;
else if (this instanceof Element e)
return 1+e.childNodes().parallelStream()
.map(x->x.count()).reduce(0,(r,x)->r+x);
throw new RuntimeException("unmatched pattern: "+this);
}
default void write(Writer out) throws IOException{
if (this instanceof Text t) out.write(t.text);
else if (this instanceof Element e){
out.write("<");
out.write(e.name());
for (var atr:e.attributes().entrySet()){
out.write(" ");
out.write(atr.getKey());
out.write("=\"");
out.write(atr.getValue());
out.write("\"");
};
out.write(">");
for (var c:e.childNodes())c.write(out);
out.write("</");
out.write(e.name());
out.write(">");
}
}
default String show() {
try{
var out = new StringWriter();
write(out);
return out.toString();
}catch(IOException e){ return "";}
}
public static Document parseXml(String xmlFileName){
try{
return
DocumentBuilderFactory
.newInstance()
.newDocumentBuilder()
.parse(new File(xmlFileName));
}catch(Exception e){return null;}
}
static int count(Node n){
var result = 1;
var cs = n.getChildNodes();
for (var i=0;i<cs.getLength();i++){
result+=count(cs.item(i));
}
return result;
}
static Set<String> tagNames(Node n){
var result = new TreeSet<String>();
tagNames(n,result);
return result;
}
static void tagNames(Node n,Set<String> result){
if (n.getNodeType()==Node.ELEMENT_NODE) result.add(n.getNodeName());
var cs = n.getChildNodes();
for (var i=0;i<cs.getLength();i++){
tagNames(cs.item(i),result);
}
}
static XML toMyXML(Node n){
if (n.getNodeType()==Node.ELEMENT_NODE){
var ats = new TreeMap<String,String>();
var as = n.getAttributes();
for (var i=0;i<as.getLength();i++){
ats.put(as.item(i).getNodeName(),as.item(i).getNodeValue());
}
var children = new ArrayList<XML>();
var r = new Element(n.getNodeName(),children,ats,null);
var cs = n.getChildNodes();
for (var i=0;i<cs.getLength();i++){
var cld = toMyXML(cs.item(i));
if (cld!=null)
children.add(cld.setParent(r));
}
return r;
}else if (n.getNodeType()==Node.TEXT_NODE
||n.getNodeType()==Node.CDATA_SECTION_NODE){
var t = n.getNodeValue().trim();
return t.isEmpty()?null:new Text(n.getNodeValue(),null);
}
if (n.getNodeType()==Node.DOCUMENT_NODE){
return toMyXML(n.getChildNodes().item(0));
}
throw new RuntimeException("unsuported node type: "+n);
}
public static void parse(File file,DefaultHandler handler)
throws Exception{
SAXParserFactory.newInstance()
.newSAXParser()
.parse(file,handler);
}
public static void parse(Reader reader,DefaultHandler handler)
throws Exception{
SAXParserFactory.newInstance()
.newSAXParser()
.parse(new InputSource(reader) ,handler);
}
public static class Count extends DefaultHandler {
public int result = 0;
@Override
public void startElement(String uri, String localName, String qName,
Attributes attributes) throws SAXException {
result++;
}
}
public static class GetTagNames extends DefaultHandler {
public Set<String> result = new TreeSet<>();
@Override
public void startElement(String uri, String localName, String qName,
Attributes attributes) throws SAXException {
result.add(qName);
}
}
public static class GetProgramCode extends DefaultHandler {
public StringBuffer result = new StringBuffer();
boolean isInCodeElement = false;
@Override public void startElement
(String uri, String localName, String qName,Attributes attributes)
throws SAXException {
if (qName.equals("code")) {
isInCodeElement = true;
}
}
@Override public void characters(char[] ch, int start, int length)
throws SAXException {
String text = new String(ch, start, length);
if (isInCodeElement)
result.append(text);
}
@Override
public void endElement(String uri, String localName, String qName)
throws SAXException {
if (qName.equals("code")) {
isInCodeElement = false;
}
}
}
static XMLEventReader staxReader(String fileName) throws XMLStreamException, IOException{
return XMLInputFactory
.newInstance()
.createXMLEventReader(new FileReader(fileName));
}
static int count(XMLEventReader reader){
var result = 0;
Iterable<Object> it = () -> reader;
for (Object o : it){
var ev = (XMLEvent) o;
if (ev.isStartElement()) result++;
}
return result;
}
public static NodeList evalXPath(String xpathExpression, Reader reader)
throws XPathExpressionException {
var xpath = XPathFactory.newInstance().newXPath();
var ns = (NodeList) xpath.evaluate(xpathExpression,
new InputSource(reader), XPathConstants.NODESET);
return ns;
}
static public String transform(File xslt,File doc){
return transform(new StreamSource(doc),new StreamSource(doc));
}
static public String transform(Source xslt,Source doc){
try{
StringWriter writer = new StringWriter();
Transformer t =
TransformerFactory
.newInstance()
.newTransformer(xslt);
t.transform(doc,new StreamResult(writer));
return writer.getBuffer().toString();
}catch (TransformerException e){
return "";
}
}
default long height(){
if (this instanceof Text) return 1;
/* ToDo */
throw new RuntimeException("unmatched pattern: "+this);
}
public static enum Axes
{self
,child
,descendant
,descendant_or_self
,parent
,ancestor
,ancestor_or_self
,following_sibling
,following
,preceding_sibling
,preceding;
}
public default List<XML> select(Axes ax){
return switch(ax){
case self -> self();
case child -> child();
case descendant -> descendant();
case descendant_or_self -> descendantOrSelf();
case parent -> parent();
case ancestor -> ancestor();
case ancestor_or_self -> ancestorOrSelf();
case following_sibling -> followingSibling();
case following -> following();
case preceding_sibling -> precedingSibling();
case preceding -> preceding();
};
}
public default List<XML> self(){
return self(new ArrayList<>());
}
public default List<XML> self(List<XML> result){
//TODO
return result;
}
public default List<XML> child(){
return child(new ArrayList<>());
}
public default List<XML> child(List<XML> result){
//TODO
return result;
}
public default List<XML> descendant(){
return descendant(new ArrayList<>());
}
public default List<XML> descendant(List<XML> result){
//TODO
return result;
}
public default List<XML> descendantOrSelf(){
return descendantOrSelf(new ArrayList<>());
}
public default List<XML> descendantOrSelf(List<XML> result){
//TODO
return result;
}
public default List<XML> parent(){
return parent(new ArrayList<>());
}
public default List<XML> parent(List<XML> result){
//TODO
return result;
}
public default List<XML> ancestor(){
return ancestor(new ArrayList<>());
}
public default List<XML> ancestor(List<XML> result){
//TODO
return result;
}
public default List<XML> ancestorOrSelf(){
return ancestorOrSelf(new ArrayList<>());
}
public default List<XML> ancestorOrSelf(List<XML> result){
//TODO
return result;
}
public default List<XML> followingSibling(){
return followingSibling(new ArrayList<>());
}
public default List<XML> followingSibling(List<XML> result){
//TODO
return result;
}
public default List<XML> precedingSibling(){
return precedingSibling(new ArrayList<>());
}
public default List<XML> precedingSibling(List<XML> result){
//TODO
return result;
}
public default List<XML> following(){
return following(new ArrayList<>());
}
public default List<XML> following(List<XML> result){
//TODO
return result;
}
public default List<XML> preceding(){
return preceding(new ArrayList<>());
}
public default List<XML> preceding(List<XML> result){
//TODO
return result;
}
public static class DOMUtil {
public static long height(Node n){
return 0;
}
public static String text(Node n){
StringBuffer result = new StringBuffer();
collectText(n, result);
return result.toString();
}
public static void collectText(Node n, StringBuffer result){
}
public static boolean containsTag(Node n, String tagname) {
return false;
}
public static Set<String> collectTagnames(Node n){
Set<String> result = ConcurrentHashMap.newKeySet();
collectTagnames(n,result);
return result;
}
public static void collectTagnames(Node n, Set<String> result) {
}
public static long getMaxHAttributeValue(Node n, String attrKey) {
long result = 0;
return result;
}
}
public static class GetBirthYears extends DefaultHandler {
public Set<Integer> result = new HashSet<>();
// ToDo
}
}
java
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