SegmentSelector (Pinot Broker 1.0.0 API)

All Known Implementing Classes:

DefaultSegmentSelector
```
public interface SegmentSelector
```
The segment selector selects the segments for the query. The segments selected should cover the whole dataset (table) without overlap.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`init(org.apache.helix.model.IdealState idealState, org.apache.helix.model.ExternalView externalView, Set<String> onlineSegments)`	Initializes the segment selector with the ideal state, external view and online segments (segments with ONLINE/CONSUMING instances in the ideal state and pre-selected by the `SegmentPreSelector`).
`void`	`onAssignmentChange(org.apache.helix.model.IdealState idealState, org.apache.helix.model.ExternalView externalView, Set<String> onlineSegments)`	Processes the segment assignment (ideal state or external view) change based on the given online segments (segments with ONLINE/CONSUMING instances in the ideal state and pre-selected by the `SegmentPreSelector`).
`Set<String>`	`select(org.apache.pinot.common.request.BrokerRequest brokerRequest)`	Selects the segments queried by the given broker request.

- Method Detail
  - init
```
void init(org.apache.helix.model.IdealState idealState,
          org.apache.helix.model.ExternalView externalView,
          Set<String> onlineSegments)
```
    Initializes the segment selector with the ideal state, external view and online segments (segments with ONLINE/CONSUMING instances in the ideal state and pre-selected by the SegmentPreSelector). Should be called only once before calling other methods.
  - onAssignmentChange
```
void onAssignmentChange(org.apache.helix.model.IdealState idealState,
                        org.apache.helix.model.ExternalView externalView,
                        Set<String> onlineSegments)
```
    Processes the segment assignment (ideal state or external view) change based on the given online segments (segments with ONLINE/CONSUMING instances in the ideal state and pre-selected by the SegmentPreSelector).
  - select
```
Set<String> select(org.apache.pinot.common.request.BrokerRequest brokerRequest)
```
    Selects the segments queried by the given broker request. The segments selected should cover the whole dataset (table) without overlap.