# com.bea.p13n.xml.util
DomHelper Class

public class DomHelper
extends `Object`

Hierarchy
  `Object`
  `DomHelper`

## Constructor Summary

DomHelper()

## Method Summary

`public static `String`` | `extractAttributeValue`(`Node` node, `String` attribute) Finds value for an attribute with a given name.
`public static `Node`` | `extractNodeByTag`(`Node` node, `String` tag) Returns a node matching a given tag.
`public static `NodeList`` | `extractNodeListByTag`(`Node` node, `String` tag) Returns a nodeList consisting of nodes that match a given tag and that are descendant elements of a given node.
`public static `String`` | `extractNodeValue`(`Node` node) Finds node value as string object Return null if node is not present or the node does not have a value
`public static `String`` | `getTagName`(`Element` e) Get the non-namespace-prefixed tag name of an element.

Methods from class `java.lang.`Object``
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

## Constructor Detail

### DomHelper

    public DomHelper()

## Method Detail

### extractAttributeValue(Node, String) Method

    public static String extractAttributeValue(Node node,
                                               String attribute)
         throws DomException

Finds value for an attribute with a given name. Attribute belongs to a given node. Only nodes that are elements will have attributes. Returns null if the given node is null or attribute does not exist

#### Parameters

node
  xml node from DOM model

attribute
  the name of the attribute

#### Exceptions

``DomException``
  if given node is not an element.

### extractNodeByTag(Node, String) Method

    public static Node extractNodeByTag(Node node,
                                        String tag)
         throws DomException

Returns a node matching a given tag. Returned node is a child of a given node. Returns null if no node has been found, or if the given node is null.

#### Parameters

node
  xml node from DOM model

tag
  specifies the name of the node to look for in the DOM model

#### Exceptions

``DomException``
  if a given node has more than one child node with a given tag.

### extractNodeListByTag(Node, String) Method

    public static NodeList extractNodeListByTag(Node node,
                                                String tag)
         throws DomException

Returns a nodeList consisting of nodes that match a given tag and that are descendant elements of a given node. Elements might not be node's direct children, but few levels deep. Returns null if no subelements have been found, or if the given node is null

#### Parameters

node
  xml node from DOM model

tag
  specifies the name of the node to look for in the DOM model

#### Exceptions

``DomException``

### extractNodeValue(Node) Method

    public static String extractNodeValue(Node node)
         throws DomException

Finds node value as string object Return null if node is not present or the node does not have a value

#### Parameters

node
  xml node from DOM model

#### Exceptions

``DomException``

### getTagName(Element) Method

    public static String getTagName(Element e)

Get the non-namespace-prefixed tag name of an element.