com.yahoo.bard.webservice.data.metric.mappers

Class TopNResultSetMapper

java.lang.Object

com.yahoo.bard.webservice.data.metric.mappers.ResultSetMapper

com.yahoo.bard.webservice.data.metric.mappers.TopNResultSetMapper

public class TopNResultSetMapper
extends ResultSetMapper

Mapper to truncate a result set produced by a groupby druid query to the requested top N rows.

Constructor Summary

Constructors

Constructor and Description
TopNResultSetMapper(int topN) Constructor.

Method Summary

Modifier and Type	Method and Description
protected Result	map(Result result, ResultSetSchema schema) Returns a transformed result row, or null if the row is removed.
ResultSet	map(ResultSet resultSet) Take a complete result set and replace it with one altered according to the rules of the concrete mapper.
protected ResultSetSchema	map(ResultSetSchema schema) Returns a transformed schema.

Methods inherited from class com.yahoo.bard.webservice.data.metric.mappers.ResultSetMapper

equals, hashCode

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

TopNResultSetMapper

public TopNResultSetMapper(int topN)

Constructor.

Parameters:

topN - The N to use when truncating to the top N in a bucket

Method Detail

map

public ResultSet map(ResultSet resultSet)

Description copied from class: ResultSetMapper

Take a complete result set and replace it with one altered according to the rules of the concrete mapper.

Overrides:

map in class ResultSetMapper

Parameters:

resultSet - The unmapped result set

Returns:

The mapped result set

map

protected Result map(Result result,
                     ResultSetSchema schema)

Description copied from class: ResultSetMapper

Returns a transformed result row, or null if the row is removed.

Specified by:

map in class ResultSetMapper

Parameters:

result - The result row being transformed

schema - The schema for that result

Returns:

The result row, a modified copy, or null (if row is eliminated)

map

protected ResultSetSchema map(ResultSetSchema schema)

Description copied from class: ResultSetMapper

Returns a transformed schema.

Specified by:

map in class ResultSetMapper

Parameters:

schema - The schema being mapped

Returns:

The same schema or a new (altered) one