Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.io.ByteArrayInputStream;
import java.util.ArrayList;
import java.util.Collection;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;

import org.w3c.dom.Document;
import org.w3c.dom.NodeList;

public class Main {
    private static String XMLSTRING = "<data><reading>"//
            + "    <MyTimeStamp> 12:00:00:02</MyTimeStamp>"//
            + "    <YVoltage>  0.5</YVoltage>" + "</reading>"//
            + "<reading>"//
            + "    <MyTimeStamp> 12:00:00:025</MyTimeStamp>"//
            + "    <YVoltage>  0.5</YVoltage>" + "</reading>"//
            + "<reading>"//
            + "    <MyTimeStamp> 12:00:00:031</MyTimeStamp>"//
            + "    <YVoltage>  0.1</YVoltage>" + "</reading>"//
            + "<reading>"//
            + "    <MyTimeStamp> 12:00:00:039</MyTimeStamp>"//
            + "    <YVoltage>  -0.1</YVoltage>" + "</reading>"//
            + "<reading>"//
            + "    <MyTimeStamp> 12:00:00:050</MyTimeStamp>"//
            + "    <YVoltage>  -0.2</YVoltage>" + "</reading>"//
            + "</data>";

    public static void main(final String[] args) throws Exception {
        Document doc = createDocument();
        XPath xpath = createXpath();
        NodeList MyTimeStampNodes = findElements("//MyTimeStamp/text()", doc, xpath);
        Collection<String> MyTimeStamps = convertToCollection(MyTimeStampNodes);
        NodeList yVoltageNodes = findElements("//YVoltage/text()", doc, xpath);
        Collection<String> yVoltages = convertToCollection(yVoltageNodes);
        for (final String MyTimeStamp : MyTimeStamps) {
            System.out.println("MyTimeStamp: " + MyTimeStamp);
        }
        for (final String yVoltage : yVoltages) {
            System.out.println("yVoltage: " + yVoltage);
        }
    }

    private static Document createDocument() throws Exception {
        DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
        documentBuilderFactory.setNamespaceAware(true);
        DocumentBuilder builder = documentBuilderFactory.newDocumentBuilder();
        Document doc = builder.parse(new ByteArrayInputStream(XMLSTRING.getBytes("ISO-8859-1")));
        return doc;
    }

    private static XPath createXpath() {
        XPathFactory xpathFactory = XPathFactory.newInstance();
        XPath xpath = xpathFactory.newXPath();
        return xpath;
    }

    private static NodeList findElements(String xpathExpression, Document doc, XPath xpath) throws Exception {
        NodeList nodes = null;
        if (doc != null) {
            XPathExpression expr = xpath.compile(xpathExpression);
            Object result = expr.evaluate(doc, XPathConstants.NODESET);
            nodes = (NodeList) result;
        }
        return nodes;
    }

    private static Collection<String> convertToCollection(final NodeList nodes) {
        final Collection<String> result = new ArrayList<String>();
        if (nodes != null) {
            for (int i = 0; i < nodes.getLength(); i++) {
                result.add(nodes.item(i).getNodeValue());
            }
        }
        return result;
    }
}