CompareFunction.java 文件源码

@Override
public FunctionRender render(FunctionRenderer renderer, RexCall call) {
  checkArity(call, 2);
  PredicateAnalyzer.checkForIncompatibleDateTimeOperands(call);

  RexNode o1 = call.getOperands().get(0);
  RexNode o2 = call.getOperands().get(1);

  FunctionRender op1 = o1.accept(renderer.getVisitor());
  FunctionRender op2 = o2.accept(renderer.getVisitor());

  boolean isTime1 = isTemporal(o1.getType());
  boolean isTime2 = isTemporal(o2.getType());

  if(isTime1 != isTime2){
    throw new RuntimeException("Can't do comparison between a date and a non-date field.");
  }

  // we need special handling in painless for temporal types and comparison other than equality/inequality.
  if(renderer.isUsingPainless() && isTime1 && type != Type.EQ && type != Type.NEQ){
    return handlePainlessTimeComparison(op1, op2);
  }

  String script = String.format("( %s %s %s )", op1.getScript(), elasticName, op2.getScript());
  return new FunctionRender(script, Iterables.concat(op1.getNulls(), op2.getNulls()));
}