Example usage for org.w3c.dom Element getElementsByTagName

Introduction

In this page you can find the example usage for org.w3c.dom Element getElementsByTagName.

Prototype

public NodeList getElementsByTagName(String name);

Source Link

Document

Returns a NodeList of all descendant Elements with a given tag name, in document order.

Usage

From source file:Main.java

/**
 * Get text data of first XML {@code org.w3c.dom.Element} of given name.
 *
 * @param elem the parent XML Element//w ww  .  j a  va2  s.  co m
 * @param name the name of the child text Element
 * @param emptyValue value to return if element exists, but is empty
 * @return text data of named child Element
 */
private static String getElementByTagName(Element elem, String name, String emptyValue) {
    NodeList nodeList = elem.getElementsByTagName(name);
    if (nodeList.getLength() == 0) {
        return null;
    }

    NodeList children = nodeList.item(0).getChildNodes();
    if (children.getLength() == 0 || children.item(0).getNodeType() != Node.TEXT_NODE) {
        return emptyValue;
    }
    return children.item(0).getNodeValue();
}

From source file:Main.java

/**
 * Get the first instance of an element by name.
 *
 * @param parent The parent to get the element from.
 * @param elementName The name of the element to look for.
 * @return The element or null if it is not found.
 *///ww  w .  j a v a2s.  c o m
public static Element getElement(Element parent, String elementName) {
    Element retval = null;
    NodeList children = parent.getElementsByTagName(elementName);
    if (children.getLength() > 0) {
        retval = (Element) children.item(0);
    }
    return retval;
}

From source file:Main.java

public static Element FindElement(Element parent_element, String element_name, String child_element_name) {
    NodeList match = parent_element.getElementsByTagName(element_name);
    if (match.getLength() == 0)
        return null;
    Element m = (Element) match.item(0);
    if (child_element_name != null)
        m = FindElement(m, child_element_name, null);
    return m;/*  ww  w  .j  av  a 2s . c o  m*/
}

From source file:Main.java

private static String getStringValue(Element element, String tagName) {
    String textValue = null;//ww w .  j  av  a 2  s.c  o  m
    NodeList nl = element.getElementsByTagName(tagName);
    if (nl != null && nl.getLength() > 0) {
        Element el = (Element) nl.item(0);
        textValue = el.getFirstChild().getNodeValue();
    }
    return textValue;
}

From source file:Main.java

/**
 * Returns the content of the first descendant of {@code ancestor} matching the specified
 * {@code tag}./*  ww  w.j  av a 2  s.c  o m*/
 * <p>
 * Example: let the {@link Element} {@code root} correspond to:
 *
 * <pre>
 * {@code <root>
 *     <name>
 *         <first>John</first>
 *         <last>Smith</last>
 *     </name>
 *     <last>BlahBlah</last>
 * </root>
 * 
 * getField(root, "last"); // returns "Smith"}
 * </pre>
 *
 * @param ancestor
 *            The starting point in the XML tree to look for descendants.
 * @param tag
 *            The tag of the desired descendant.
 * @return The content of the first descendant of {@code ancestor} matching the tag, or
 *         {@code null} if no such descendant exists.
 */
public static String getField(Element ancestor, String tag) {
    NodeList children = ancestor.getElementsByTagName(tag);
    if (children.getLength() == 0) {
        return null;
    }
    return getContent(children.item(0));
}

From source file:Main.java

/**
 * Return content of child element with given tag name.
 * If more than one children with this name are present, the content of the last
 * element is returned.//from  w ww . j av  a2  s .  c  o m
 *
 * @param elem
 * @param childTagName
 * @return content of child element or null if no child element with this name was found
 */
public static String getChildText(Element elem, String childTagName) {
    NodeList nodeList = elem.getElementsByTagName(childTagName);
    int len = nodeList.getLength();
    if (len == 0) {
        return null;
    } else {
        return getElementText((Element) nodeList.item(len - 1));
    }
}

From source file:Main.java

public static String getGrandSonElementValueByTagName(Element element, String parentName, String eleName) {

    NodeList nl = element.getElementsByTagName(parentName);
    if (null == nl) {
        return null;
    }/*from  w  ww. j  a  va2s.com*/
    Node item = nl.item(0);
    return getChildElementValueByTagName((Element) item, eleName);
}

From source file:Main.java

public static String findNodeValue(Element firstElement, String name) {
    String nodeValue = null;// w  w  w  .  j  av  a  2  s.  c o  m
    NodeList firstNameList = firstElement.getElementsByTagName(name);
    Element firstNameElement = (Element) firstNameList.item(0);

    NodeList textFNList = firstNameElement.getChildNodes();

    if (textFNList.getLength() > 0) {
        nodeValue = (textFNList.item(0)).getNodeValue();
    }
    return nodeValue;
}

From source file:Main.java

/**
 * Adds or replaces node in parent./*w  w w .j  av  a2 s.co  m*/
 * @param parent
 * @param node
 * @throws Exception - Node cannot exist more than once,
 * i.e. multiple nodes with the same name cannot exist in parent.
 */
public static void replaceSingleNode(Element parent, final Node node) throws RuntimeException {

    NodeList nodes = parent.getElementsByTagName(node.getNodeName());

    if (nodes.getLength() > 1) {
        throw new RuntimeException(
                "Parent element contains multiple nodes with the name " + node.getNodeName());
    }
    if (nodes.getLength() == 0) {
        parent.appendChild(node);
    } else {
        parent.replaceChild(node, nodes.item(0));
    }
}

From source file:Main.java

/**
 * get the value of an Element in the Xml Document.
 * finds the first occurance of the parent element and then searches its children
 * for the first occurance of the element and retrieves its value.
 * @param root the root Element./*from   w  ww.  j a  v a  2s  .  c om*/
 * @param parent the name of the parent element to search for.
 * @param elemName the name of the child element to search for.
 * @return String the element value or null if not found.
 */
public static String getSubElementValue(Element root, String parent, String elemName) {
    NodeList nl = root.getElementsByTagName(parent);
    String value = null;
    if (null == nl) {
        return (null);
    }
    Node node = nl.item(0);
    nl = node.getChildNodes();
    if (null == nl) {
        return (null);
    }

    boolean found = false;
    for (int i = 0; !found && i < nl.getLength(); ++i) {
        Node n = nl.item(i);
        if (elemName.equals(n.getNodeName())) {
            value = n.getFirstChild().getNodeValue().trim();
            found = true;
            break;
        } // if
    } // for
    return (value);
}