private void expression(Map<String, Boolean> fields, Stack<Boolean> stack, ConditionLexer lex)
throws IOException, AnnotationParseException {
ConditionToken tok = lex.lex();
if (tok == null) {
return;
}
switch (tok.type) {
case FIELD:
if (!fields.containsKey(tok.value)) {
throw new AnnotationParseException("Field not found", lex.yyline());
} else {
stack.push(fields.get(tok.value));
}
expressionRest(fields, stack, lex);
break;
case NOT:
expression(fields, stack, lex);
Boolean invOp = stack.pop();
stack.push(!invOp);
break;
case PARENT_OPEN:
expression(fields, stack, lex);
tok = lex.lex();
if (tok.type != ConditionTokenType.PARENT_CLOSE) {
throw new AnnotationParseException("End of parent expected", lex.yyline());
}
expressionRest(fields, stack, lex);
break;
default:
throw new AnnotationParseException("Expression expected", lex.yyline());
}
}
public Set<String> getFields() throws AnnotationParseException {
Set<String> ret = new HashSet<>();
ConditionLexer lex = new ConditionLexer(new StringReader(prepareCond()));
ConditionToken tok;
try {
while ((tok = lex.lex()) != null) {
if (tok.type == ConditionTokenType.FIELD) {
ret.add(tok.value);
}
}
} catch (IOException ex) {
throw new AnnotationParseException("Invalid condition:" + prepareCond(), lex.yyline());
}
return ret;
}
public boolean eval(Map<String, Boolean> fields) throws AnnotationParseException {
ConditionLexer lex = new ConditionLexer(new StringReader(prepareCond()));
Stack<Boolean> stack = new Stack<>();
try {
expression(fields, stack, lex);
} catch (IOException | EmptyStackException ex) {
throw new AnnotationParseException("Invalid condition:" + prepareCond(), lex.yyline());
}
if (prepareCond().isEmpty()) {
return true;
}
if (stack.size() != 1) {
throw new AnnotationParseException("Invalid condition:" + prepareCond(), lex.yyline());
}
return stack.pop();
}
private void expressionRest(Map<String, Boolean> fields, Stack<Boolean> stack, ConditionLexer lex)
throws IOException, AnnotationParseException {
ConditionToken tok = lex.lex();
if (tok == null) {
return;
}
switch (tok.type) {
case AND:
Boolean andOp1 = stack.pop();
expression(fields, stack, lex);
Boolean andOp2 = stack.pop();
stack.push(andOp1 && andOp2);
break;
case OR:
Boolean orOp1 = stack.pop();
expression(fields, stack, lex);
Boolean orOp2 = stack.pop();
stack.push(orOp1 || orOp2);
break;
default:
lex.pushback(tok);
}
}
