RefreshHandler (Flink : Table : Common 2.0.0 API)

All Known Implementing Classes:

ContinuousRefreshHandler
```
@PublicEvolving
public interface RefreshHandler
```
This interface represents the meta information of current materialized table background refresh pipeline. The refresh mode maybe continuous or full, the meta information in the two modes is not consistent, so user need to implementation this interface according to different case.
In continuous mode, the meta information maybe contains { "clusterType": "yarn", "clusterId": "xxx", "jobId": "yyyy" }.
In full mode, the meta information maybe contains { "endpoint": "xxx", "workflowId": "yyy" }. Due to user may use different workflow scheduler in this mode, user should implement this interface according to their plugin.
This interface will be serialized to bytes by RefreshHandlerSerializer, then store to Catalog for further operation.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`String`	`asSummaryString()`	Returns a string that summarizes this refresh handler meta information for printing to a console or log.

- Method Detail
  - asSummaryString
```
String asSummaryString()
```
    Returns a string that summarizes this refresh handler meta information for printing to a console or log.