private Constraint<T> readConstraint(XmlElement element) throws XmlParseException {
		String name = element.getName();
		Constraint<T> constraint = getConstraint(name);
		if (constraint == null) {
			return null;
		}
		constraint.loadConstraintData(new ConstraintData(element.getAttributes()));
		return constraint;
	}
Loads the tree from an xml constraint file. Note: this method can be called multiple times,
with each call appending to the existing tree. 
@param file the file that contains the xml for the constraint.
@throws IOException if an I/O problem occurs reading from the stream.
@throws XmlParseException if the XML is not property formatted or a tag that is not
a constraint name or property name is encountered.
Ghidra/Framework/Generic/src/main/java/generic/constraint/DecisionTree.java