Parsing, Creating, and Transforming XML Documents - Beginning Java 7 - page 959

nodes), Node getFirstChild() (return the node's first child), and Node
getLastChild() (return the node's last child). For nodes with multiple children,
you'll find the NodeList getChildNodes() method to be handy. This method
returnsan org.w3c.dom.NodeList instancewhose int getLength() method
returnsthenumberofnodesinthelist,andwhose Node item(int index) method
returnsthenodeatthe index thpositioninthelist(ornullwhen index 'svalueisnot
valid—it's less than 0 or greater than or equal to getLength() 's value).
Node declaresfourmethodsformodifyingthetreebyinserting,removing,replacing,
andappendingchildnodes.The Node insertBefore(Node newChild, Node
refChild) method inserts newChild before the existing node specified by re-
fChild and returns newChild , Node removeChild(Node oldChild) re-
moves the child node identified by oldChild from the tree and returns oldChild ,
Node replaceChild(Node newChild, Node oldChild) replaces
oldChild with newChild and returns oldChild , and Node ap-
pendChild(Node newChild) adds newChild to the end of the current node's
child nodes and returns newChild .
Finally, Node declares several utility methods, including Node
cloneNode(boolean deep) (create and return a duplicate of the current node,
recursively cloning its subtree when true is passed to deep ),and void normal-
ize() (descendthetreefromthegivennodeandmergealladjacenttextnodes,delet-
ing those text nodes that are empty).
Tip To obtain an element node's attributes, first call Node 's NamedNodeMap
getAttributes() method. This method returns an
org.w3c.dom.NamedNodeMap implementation when the node represents an ele-
ment; otherwise, it returns null. In addition to declaring methods for accessing these
nodesbyname(e.g., Node getNamedItem(String name) ), NamedNodeMap
declares int getLength() and Node item(int index) methodsforreturn-
ingallattributenodesby index .Youwouldthenobtainthe Node 'snamebycallinga
method such as getNodeName() .
As well as inheriting Node 's constants and methods, Document declares its own
methods. For example, you can call Document 's String getXmlEncoding() ,
boolean getXmlStandalone() , and String getXmlVersion() methods
to return the XML declaration's encoding , standalone , and version attribute
values, respectively.