Creating and Modifying XML Documents - Beginning Java - page 1319

break;
case "color":
setColorFromXML(aNode);
break;
case "bounds":
setBoundsFromXML(aNode);
break;
case "endpoint":
NamedNodeMap coords = aNode.getAttributes();
line = new Line2D.Double();
line.x2 =
Double.valueOf(((Attr)(coords.getNamedItem("x"))).getValue());
line.y2 =
Double.valueOf(((Attr)(coords.getNamedItem("y"))).getValue());
break;
default:
System.err.println("Invalid node in <line>: " + aNode);
break;
}
}
}
Directory "Sketcher reading and writing XML"
You set the angle for the line by calling the method that you added to the base class for this purpose.
The getChildNode() method returns the child nodes in a NodeList object. You iterate over all the nodes
in the childNodes list in the for loop. Calling getItem() for childNodes returns the Node object at the
index position you pass to the method. You then process the node in the switch statement, selecting on the
basis of the node name, which is a String . Each of the base class fields are set by calling one or other of
the methods you have defined. For the <endpoint> node, you reconstruct the Line2D.Double object from
the attributes for the node. Calling the no-arg constructor for Line2D.Double creates an object with the start
and end points as (0,0), so you just have to set the end point coordinates, which are stored in line.x2 and
line.y2 .
Creating a Rectangle Object from an XML Node
Most of the code to reconstruct an Element.Rectangle object is the same as for a line:
// Create Rectangle object from XML node
public Rectangle(Node node) {
setAngleFromXML(node);
NodeList childNodes = node.getChildNodes();
Node aNode = null;
for(int i = 0 ; i < childNodes.getLength() ; ++i) {
aNode = childNodes.item(i);
switch(aNode.getNodeName()) {
case "position":
setPositionFromXML(aNode);