Total.java

package org.softlang.company.features;

import org.xml.sax.Attributes;
import org.xml.sax.helpers.DefaultHandler;

/**
 * Compute the total all salaries of a company
 */
public class Total extends DefaultHandler {

    private static String ns = "http://www.company.softlang.org/company.xsd";
    private boolean isSalary = false;
    private double total = 0;

    /**
     * Return the final result of query for totaling salaries.
     */
    public double getTotal() { 
        return total; 
    }

    /**
     * Handle "start element"
     */
    public void startElement(
            String uri, 
            String name,
            String qName,
            Attributes atts) {
        isSalary = (uri.equals(ns) && name.equals("salary"));
    }

    /**
     * Handle "end element"
     */
    public void endElement(
            String uri,
            String name,
            String qName) {
        isSalary = false;
    }

    /**
     * Handle "characters"
     */
    public void characters(
            char ch[],
            int start,
            int length) {
        if (isSalary) {
            String str = String.valueOf(ch, start, length);
            double salary = Double.parseDouble(str);
            total += salary;
        }
    }

}