protected boolean needsImplicitCastForDecimal(GenericUDF udf) {
    Class<?> udfClass = udf.getClass();
    if (udf instanceof GenericUDFBridge) {
      udfClass = ((GenericUDFBridge) udf).getUdfClass();
    }
    return udfsNeedingImplicitDecimalCast.contains(udfClass);
  }
Context class for vectorization execution.
Main role is to map column names to column indices and serves as a
factory class for building vectorized expressions out of descriptors.
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/VectorizationContext.java