private CommonTokenStream tokens;
public void parse(Snapshot snapshot, Task task, SourceModificationEvent event) {
this.snapshot = snapshot;
ANTLRStringStream input = new ANTLRStringStream(snapshot.getText().toString());
lexer = new PL_SQLLexer(input);
tokens = new CommonTokenStream(lexer);
parser = new PL_SQLParser(tokens);
try {
PL_SQLParser.grammar_def_return ret = parser.grammar_def();
tree = (CommonTree) ret.getTree();