CustomizedConvertRule (Flink : 2.0-preview1 API)

java.lang.Object
- org.apache.flink.table.planner.expressions.converter.CustomizedConvertRule

All Implemented Interfaces:

CallExpressionConvertRule
```
@Internal
public class CustomizedConvertRule
extends Object
implements CallExpressionConvertRule
```
Customized CallExpressionConvertRule, Functions conversion here all require special logic, and there may be some special rules, such as needing get the literal values of inputs, such as converting to combinations of functions, to convert to RexNode of calcite.

Nested Class Summary
- Nested classes/interfaces inherited from interface org.apache.flink.table.planner.expressions.converter.CallExpressionConvertRule
  CallExpressionConvertRule.ConvertContext

Constructor Summary

Constructors
Constructor Description

CustomizedConvertRule()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`Optional<org.apache.calcite.rex.RexNode>`	`convert(CallExpression call, CallExpressionConvertRule.ConvertContext context)`	Convert call expression with context to RexNode.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - CustomizedConvertRule
```
public CustomizedConvertRule()
```
- Method Detail
  - convert
```
public Optional<org.apache.calcite.rex.RexNode> convert(CallExpression call,
                                                        CallExpressionConvertRule.ConvertContext context)
```
    Description copied from interface: CallExpressionConvertRule
    
    Convert call expression with context to RexNode.
    
    Specified by:
    
    convert in interface CallExpressionConvertRule
    
    Returns:
    
    Success return RexNode of Optional.of(T), Fail return Optional.empty().