private StructureType assignStructureType(Element structure) throws VisualizerLoadException {
String name = structure.getName().toLowerCase();
if (name.compareTo("graph") == 0) {
if (structure.getAttributeValue("weighted").compareTo("true") == 0)
return new Graph_Network("NETWORK");
else return new Graph_Network("GRAPH");
} else if (name.equals("array")) return new MD_Array();
else if (name.equals("no3darray")) return new No3darray();
else if (name.equals("linkedlist")) return new VisLinkedList();
else if (name.equals("no3dlinkedlist")) return new No3dLinkedList();
else if (name.equals("linkedlistnonull")) return new VisLinkedListNoNull();
else if (name.equals("bargraph")) return new BarScat("BAR");
else if (name.equals("scattergraph"))
return new BarScat(
"SCAT"); // not implemented in xml dtd, and does not have a load-from-xml method defined
else if (name.equals("stack")) return new Stack();
else if (name.equals("queue")) return new Queue();
else if (name.equals("tree")) {
if (structure.getChild("binary_node") != null) return new BinaryTree();
else return new GeneralTree();
} else if (name.equals("text")) return new TextStructure();
// if the XML element name is different from your structure's name, you can do something like
// this:
// else if( name.equalsIgnoreCase("node"))
// return new Node();
else if (name.equals("legend")) return new LegendofColors();
else {
// try dynamic typing
try {
return assignStructureType(name);
} catch (Exception e) {
throw new VisualizerLoadException(
"Unable to instantiate class \"" + name + "\":\n" + e.getMessage());
}
}
}
private void load_snap_from_xml(Element snap, StructureCollection structs, LinkedList tempList)
throws VisualizerLoadException {
Iterator iterator = snap.getChildren().iterator();
if (!iterator.hasNext()) throw new VisualizerLoadException("Ran out of elements");
structs.loadTitle((Element) (iterator.next()), tempList, this);
structs.calcDimsAndStartPts(tempList, this);
if (!iterator.hasNext()) return;
Element child = (Element) iterator.next();
if (child.getName().compareTo("doc_url") == 0) {
// load the doc_url
add_a_documentation_URL(child.getText().trim());
if (!iterator.hasNext()) return;
child = (Element) iterator.next();
}
if (child.getName().compareTo("pseudocode_url") == 0) {
// load the psuedocode_url
add_a_pseudocode_URL(child.getText().trim());
if (!iterator.hasNext()) return;
child = (Element) iterator.next();
}
if (child.getName().compareTo("audio_text") == 0) {
// load the psuedocode_url
add_audio_text(child.getText().trim());
if (!iterator.hasNext()) return;
child = (Element) iterator.next();
}
// create & load the individual structures, hooking them into the StructureCollection.
// linespernode : calculate it at end of loadStructure call
while (child.getName().compareTo("question_ref") != 0) {
StructureType child_struct = assignStructureType(child);
child_struct.loadStructure(child, tempList, this);
structs.addChild(child_struct);
if (!iterator.hasNext()) return;
child = (Element) iterator.next();
}
if (child.getName().compareTo("question_ref") == 0) {
// set up question ref
add_a_question_xml(child.getAttributeValue("ref"));
} else
// should never happen
throw new VisualizerLoadException(
"Expected question_ref element, but found " + child.getName());
if (iterator.hasNext()) {
child = (Element) iterator.next();
throw new VisualizerLoadException(
"Found " + child.getName() + " when expecting end of snap.");
}
} // load_snap_from_xml