Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
import java.io.File;
import java.util.HashMap;
import java.util.Map;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

public class Main {
    /**
     * Create a map based on a xml file and a xpath expression and an attribute.
     * Treat attribute's value as map's key, treat xpath expression represented node's text content as map's value.
     * 
     * @param xmlFile handled xml file
     * @param xpathExp xpath express, such as "//var"
     * @param arrtibute attribute, such as "name"
     * @return created Map object
     * @throws Exception
     */
    public static Map<String, String> readXmlToMap(String xmlFile, String xpathExp, String arrtibute)
            throws Exception {
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        factory.setIgnoringElementContentWhitespace(true);

        DocumentBuilder db = factory.newDocumentBuilder();
        Document xmlDoc = null;
        try {
            xmlDoc = db.parse(new File(xmlFile));
        } catch (SAXException e) {
            if ("Premature end of file.".equals(e.getMessage()))
                System.out.println("Maybe your local data file has no content.");
            //e.printStackTrace();
            return new HashMap<String, String>();
        }
        XPathFactory xpathFactory = XPathFactory.newInstance();
        XPath xpath = xpathFactory.newXPath();
        NodeList varList = (NodeList) xpath.evaluate(xpathExp, xmlDoc, XPathConstants.NODESET);
        Map<String, String> dataMap = new HashMap<String, String>();
        for (int i = 0; i < varList.getLength(); i++)
            dataMap.put(varList.item(i).getAttributes().getNamedItem(arrtibute).getNodeValue(),
                    varList.item(i).getTextContent());

        return dataMap;
    }
}