Xml.java

/*

GOTO Xml_teszt.java

https://szit.hu/doku.php?id=oktatas:programozas:java:java_xml
http://faragocsaba.hu/java-extlibs-xml
https://javaoktato.com/java_2ed/chapter_jaxb.pdf
https://labex.io/tutorials/java-how-to-access-elements-and-attributes-in-an-xml-document-with-java-413933
https://dom4j.github.io/javadoc/2.1.4/

*/

import java.io.*;
import java.util.*;

import org.dom4j.*;
import org.dom4j.io.*;
import org.dom4j.dom.*;

public class Xml
{
    protected Document document;
    protected Element root;
    protected int levelCounter = 0;
    protected StringBuilder xmlAsText = new StringBuilder();

    public Xml ( File f ) throws DocumentException
    {
        try
        {
            SAXReader reader = new SAXReader();
            document = reader.read( f );
        }
        catch ( DocumentException e )
        {
            e.printStackTrace();
        }
        init();
    }

    public Xml ( String fname ) throws DocumentException
    {
        this( new File( fname ) );
    }

    private void init ()
    {
        root = document.getRootElement();
    }

    public void write ( String fname ) throws Exception
    {
        try
        {
            FileOutputStream newFile = new FileOutputStream( fname );
            XMLWriter writer = new XMLWriter( newFile, OutputFormat.createPrettyPrint() );
            //document = ( Document) ( ( DOMDocument) document ).setXmlStandalone(true);
            writer.write( document );
        }
        catch ( Exception e )
        {
            e.printStackTrace();
        }
    }

    /* Fast looping
    [ https://dom4j.github.io/#looping ]
     */

    public void treeWalk()
    {
        treeWalk( document );
    }

    public void treeWalk( Document document )
    {
        treeWalk( document.getRootElement() );
    }

    public void treeWalk( Element element )
    {
        if ( levelCounter == 0 )
        {
            xmlAsText.append( "[" + levelCounter + "] " + element.getName() + " " + element.attributes().size() + "\n" );
        }
        levelCounter++;
        String previousParent = "";
        String indent="   ";
        for (int i = 0; i < element.nodeCount(); i++)
        {
            Node node = element.node( i );
            if (node instanceof Element)
            {
                previousParent = node.getParent().getName();
                treeWalk( (Element) node );
            }
            else
            {   //if ( node.getText() != null && ! node.getText().equals("") )
                //if ( ! node.getText().trim().equals("") )
                if ( previousParent != element.getName() )
                {
                    xmlAsText.append( indent.repeat(levelCounter) +
                                    "[" + levelCounter + "] " +
                                    element.getName() +
                                    ( ! node.getText().trim().equals("") ? " '" + node.getText().trim() + "'" : "" ) + "\n"
                                    );
                    for (int j = 0; j < element.attributes().size(); j++)
                    {
                        Attribute a = element.attribute(j);
                        xmlAsText.append( indent.repeat(levelCounter) +
                                        "[" + levelCounter + "] {" +
                                        a.getName() + " '" +
                                        a.getValue() + "'} " + "\n"
                                        );
                    }
                }
            }
        }
        levelCounter--;
    }

}