Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;

import org.w3c.dom.Document;

import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

public class Main {
    /**
     * Finds a node in a document and returns the value from an attribute of
     * this node. If there are multiple nodes with the specified tag name, the
     * attribute value of the first node found will be returned.
     * 
     * @param document
     *            the document.
     * @param nodeName
     *            the name of the node .
     * @param attributeName
     *            the name of the node's attribute.
     * @return the value of the node's attribute or <code>null</code> if either
     *         no node with the specified tag name or no attribute with the
     *         specified attribute name could be found.
     */
    public static String getAttributeValueFromNode(Document document, String nodeName, String attributeName) {
        Node node = getNode(document, nodeName);
        if (node != null) {
            Node attribute = getAttributeValue(node, attributeName);
            if (attribute != null) {
                return attribute.getNodeValue();
            }
        }
        return null;
    }

    /**
     * Gets the first node with the specified tag name from the given document.
     * If there are multiple nodes with the specified tag name, the first node
     * found will be returned.
     * 
     * @param doc
     *            the document
     * @param tagname
     *            the tag name of the node to find.
     * @return the first node found with the specified tag name or
     *         <code>null</code> if no node with that name could be found.
     */
    public static Node getNode(Document doc, String tagname) {
        NodeList nl = doc.getElementsByTagName(tagname);
        if (!isEmpty(nl)) {
            return nl.item(0);
        }
        return null;
    }

    /**
     * Gets the value from a node's attribute.
     * 
     * @param node
     *            the node.
     * @param attributeName
     *            the name of the attribute.
     * @return the value of the attribute with the specified name or
     *         <code>null</code> if there is no attribute with that name.
     */
    public static Node getAttributeValue(Node node, String attributeName) {
        return (node.hasAttributes()) ? node.getAttributes().getNamedItem(attributeName) : null;

    }

    /**
     * Null-safe check if a nodelist is empty.
     * 
     * @param nodeList
     *            the nodelist to check.
     * @return <code>true</code> if the given nodelist is <code>null</code> or
     *         empty.
     */
    public static boolean isEmpty(NodeList nodeList) {
        return nodeList == null || nodeList.getLength() == 0;
    }
}