private Expression translate0(RexNode expr) { if (expr instanceof RexInputRef) { // TODO: multiple inputs, e.g. joins final Expression input = getInput(0); final int index = ((RexInputRef) expr).getIndex(); final List<RelDataTypeField> fields = program.getInputRowType().getFieldList(); final RelDataTypeField field = fields.get(index); if (fields.size() == 1) { return input; } else if (input.getType() == Object[].class) { return Expressions.convert_( Expressions.arrayIndex(input, Expressions.constant(field.getIndex())), Types.box(JavaRules.EnumUtil.javaClass(typeFactory, field.getType()))); } else { return Expressions.field(input, field.getName()); } } if (expr instanceof RexLocalRef) { return translate(program.getExprList().get(((RexLocalRef) expr).getIndex())); } if (expr instanceof RexLiteral) { return Expressions.constant( ((RexLiteral) expr).getValue(), typeFactory.getJavaClass(expr.getType())); } if (expr instanceof RexCall) { final RexCall call = (RexCall) expr; final SqlOperator operator = call.getOperator(); final ExpressionType expressionType = SQL_TO_LINQ_OPERATOR_MAP.get(operator); if (expressionType != null) { switch (operator.getSyntax()) { case Binary: return Expressions.makeBinary( expressionType, translate(call.getOperands()[0]), translate(call.getOperands()[1])); case Postfix: case Prefix: return Expressions.makeUnary(expressionType, translate(call.getOperands()[0])); default: throw new RuntimeException("unknown syntax " + operator.getSyntax()); } } Method method = SQL_OP_TO_JAVA_METHOD_MAP.get(operator); if (method != null) { List<Expression> exprs = translateList(Arrays.asList(call.operands)); return !Modifier.isStatic(method.getModifiers()) ? Expressions.call(exprs.get(0), method, exprs.subList(1, exprs.size())) : Expressions.call(method, exprs); } switch (expr.getKind()) { default: throw new RuntimeException("cannot translate expression " + expr); } } throw new RuntimeException("cannot translate expression " + expr); }
public static Expression translateCondition( List<Expression> inputs, RexProgram program, JavaTypeFactory typeFactory, List<Statement> list) { List<Expression> x = new RexToLixTranslator(program, typeFactory, inputs) .translate(list, Collections.singletonList(program.getCondition())); assert x.size() == 1; return x.get(0); }
/** * Gets the expression for an input and counts it. * * @param index Input ordinal * @return Expression to which an input should be translated */ private Expression getInput(int index) { Slot slot = inputSlots.get(index); if (list == null) { slot.count++; } else { if (slot.count > 1 && slot.parameterExpression == null) { slot.parameterExpression = Expressions.parameter(slot.expression.type, "current" + index); list.add(Expressions.declare(Modifier.FINAL, slot.parameterExpression, slot.expression)); } } return slot.parameterExpression != null ? slot.parameterExpression : slot.expression; }