public Transformer(FiniteStateTable dfa) {
this.dfa = dfa;
flatFST = new FlatFST();
used = new BitSet(dfa.getTransitionTable().size());
used.clear();
statePosition = new int[dfa.getDFA().size()];
}
public static void main(String[] args) {
if (args.length < 1) {
System.out.printf("ReadFST file.fst\n");
System.exit(0);
}
FiniteStateTable fst = new FiniteStateTable();
try {
fst.readFSTFile(args[0]);
fst.traverseDFA(0, 0, new StringBuilder(), 0, 0);
} catch (FileNotFoundException ex) {
ex.printStackTrace();
} catch (IOException ex) {
ex.printStackTrace();
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
}
}
//
// transform data structure from DFA+TransitionTable to FlatFST
//
void transform() {
int current = 0;
int beginning = 0;
int i;
// iteration through all states
for (int state = 0; state < dfa.getDFA().size(); state++) {
// check all transition space
current = beginning - 1;
do {
do { // find unused space
for (++current; used.get(current); current++) ;
// make sure for unused space
} while ((dfa.ofFinished(state) == true) && flatFST.isUsed(current));
// check all transition space
for (i = 0; i < dfa.ofSize(state); i++) {
if (flatFST.isUsed(current + dfa.ofChar(state, i))) {
break;
}
}
} while (i < dfa.ofSize(state));
// copy all transitions into flatfst position
for (i = 0; i < dfa.ofSize(state); i++) {
flatFST.put(
current + dfa.ofChar(state, i),
new FSTType(dfa.ofChar(state, i), dfa.ofValue(state, i), dfa.ofNext(state, i)));
}
if (dfa.ofFinished(state)) {
flatFST.setFinished(current);
}
// set state position
statePosition[state] = current;
used.set(current);
// move beginning position
for (; used.get(beginning); beginning++) ;
}
// free memory
used = null;
// most import concept of flatFST
// combine state(position of FST) and transition
for (i = 0; i < flatFST.size(); i++) {
if (flatFST.isUsed(i) && !flatFST.isFinished(i)) {
flatFST.get(i).next = statePosition[flatFST.get(i).next];
}
}
}
