* transformation process
*/
public static OperationPair<DocOp> transform(DocOp clientOp,
DocOp serverOp) throws TransformException {
try {
Decomposition c = Decomposer.decompose(clientOp);
Decomposition s = Decomposer.decompose(serverOp);
DocOp ci = c.insertion;
DocOp cp = c.preservation;
DocOp cd = c.deletion;
DocOp si = s.insertion;
DocOp sp = s.preservation;