/** Compiles UnaryExpression */
@Override
public void visit(UnaryExpression expression) {
if (expression == null) {
throw new ArgumentException(EXPRESSION + E_IS_NULL);
}
expression.getExpression().accept(this);
switch (expression.getType()) {
case NOT:
result.setResult(new Not(result.getResult()));
break;
case NEGATE:
result.setResult(new Negate(result.getResult()));
break;
}
}
@Override
public void visit(AssignmentExpression assignment) {
if (assignment == null) {
throw new ArgumentException(ASSIGNMENT + E_IS_NULL);
}
/** processes the left hand expression and saves the value to result */
assignment.getLeft().accept(this);
LogicalExpression left = result.getResult();
// LHS must always be a variable.
if (!(left instanceof Variable)) {
throw new ArgumentException(E_ASSIGNMENT_LHS_NOT_VARIABLE);
}
assignment.setLeft(left);
/** processes the right hand expression and saves the value to result */
assignment.getRight().accept(this);
assignment.setRight(result.getResult());
/** No magic here, just set the original instance */
result.setResult(assignment);
}
private LogicalExpression evaluate(LogicalExpression expression) {
expression.accept(this);
return result.getResult();
}
/** Compiles BinaryExpressions */
@Override
public void visit(BinaryExpression expression) {
if (expression == null) {
throw new ArgumentException(EXPRESSION + E_IS_NULL);
}
/** processes the left hand expression and saves the value to result */
expression.getLeft().accept(this);
LogicalExpression left = result.getResult();
/** processes the right hand expression and saves the value to result */
expression.getRight().accept(this);
LogicalExpression right = result.getResult();
switch (expression.getType()) {
case AND:
result.setResult(new And(left, right));
break;
case OR:
result.setResult(new Or(left, right));
break;
case DIV:
result.setResult(new Divide(left, right));
break;
case EQ:
result.setResult(new Equal(left, right));
break;
case GT:
result.setResult(new Greater(left, right));
break;
case GTE:
result.setResult(new GreaterEqual(left, right));
break;
case LT:
result.setResult(new Lesser(left, right));
break;
case LTE:
result.setResult(new LesserEqual(left, right));
break;
case MINUS:
result.setResult(new Minus(left, right));
break;
case MOD:
result.setResult(new Modulo(left, right));
break;
case NE:
result.setResult(new NotEqual(left, right));
break;
case PLUS:
result.setResult(new Plus(left, right));
break;
case MULT:
result.setResult(new Multiply(left, right));
break;
case POW:
result.setResult(new Power(left, right));
break;
}
}