0a95ebf602
This pr did these things: 1. Change the nullable mode of 'from_unixtime' and 'parse_url' from DEPEND_ON_ARGUMENT to ALWAYS_NULLABLE, which nullable configuration was missing previously. 2. Add some new interfaces for origin NullableMode. This change inspired by the grammar of scala's mix-in trait, It help us to quickly understand the traits of function without read the lengthy procedural code and save the work to write some template code, like `class Substring extends ScalarFunction implements ImplicitCastInputTypes, PropagateNullable`. These are the interfaces: - PropagateNullable: equals to NullableMode.DEPEND_ON_ARGUMENT - AlwaysNullable: equals to NullableMode.ALWAYS_NULLABLE - AlwaysNotNullable: equals to NullableMode.ALWAYS_NOT_NULLABLE - others ComputeNullable: equals to NullableMode.CUSTOM 3. Add `GenerateScalarFunction` to generate nereids-style function code from legacy functions, but not actual generate any new function class yet, because the function's trait is not ready for use. I need add some traits for the legacy function's CompareMode and NonDeterministic, this thought is the same as ComputeNullable.
# Licensed to the Apache Software Foundation (ASF) under one # or more contributor license agreements. See the NOTICE file # distributed with this work for additional information # regarding copyright ownership. The ASF licenses this file # to you under the Apache License, Version 2.0 (the # "License"); you may not use this file except in compliance # with the License. You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, # software distributed under the License is distributed on an # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY # KIND, either express or implied. See the License for the # specific language governing permissions and limitations # under the License. # fe-common This module is used to store some common classes of other modules. # spark-dpp This module is Spark DPP program, used for Spark Load function. Depends: fe-common # fe-core This module is the main process module of FE. Depends: fe-common, spark-dpp