Method toRex

piglet/src/main/java/org/apache/calcite/piglet/Handler.java:327–360

(Ast.Node exp)

  }

  private RexNode toRex(Ast.Node exp) {
    final Ast.Call call;
    switch (exp.op) {
    case LITERAL:
      return builder.literal(((Ast.Literal) exp).value);
    case IDENTIFIER:
      final String value = ((Ast.Identifier) exp).value;
      if (value.matches("^\\$[0-9]+")) {
        int i = Integer.valueOf(value.substring(1));
        return builder.field(i);
      }
      return builder.field(value);
    case DOT:
      call = (Ast.Call) exp;
      final RexNode left = toRex(call.operands.get(0));
      final Ast.Identifier right = (Ast.Identifier) call.operands.get(1);
      return builder.dot(left, right.value);
    case EQ:
    case NE:
    case GT:
    case GTE:
    case LT:
    case LTE:
    case AND:
    case OR:
    case NOT:
    case PLUS:
    case MINUS:
      call = (Ast.Call) exp;
      return builder.call(op(exp.op), toRex(call.operands));
    default:
      throw new AssertionError("unknown op " + exp.op);
    }
  }

  private static SqlOperator op(Ast.Op op) {
    switch (op) {