Package org.apache.druid.query.rowsandcols

Class MapOfColumnsRowsAndColumns

java.lang.Object

org.apache.druid.query.rowsandcols.MapOfColumnsRowsAndColumns

All Implemented Interfaces:

RowsAndColumns

public class MapOfColumnsRowsAndColumns
extends Object
implements RowsAndColumns

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	MapOfColumnsRowsAndColumns.Builder

Constructor Summary

Constructors

Constructor	Description
MapOfColumnsRowsAndColumns(Map<String,Column> mapOfColumns, int numRows)

Method Summary

Modifier and Type	Method	Description
<T> T	as(Class<T> clazz)	Asks the RowsAndColumns to return itself as a concrete implementation of a specific interface.
static MapOfColumnsRowsAndColumns.Builder	builder()
Column	findColumn(String name)	Finds a column by name.
static MapOfColumnsRowsAndColumns	fromMap(Map<String,? extends Column> map)
static MapOfColumnsRowsAndColumns	fromResultRow(ArrayList<ResultRow> objs, RowSignature signature)
static MapOfColumnsRowsAndColumns	fromRowObjects(Object[][] objs, RowSignature signature)
Set<String>	getColumnNames()	The set of column names available from the RowsAndColumns
int	numRows()	The number of rows in the RowsAndColumns object
static MapOfColumnsRowsAndColumns	of(String name, Column col)
static MapOfColumnsRowsAndColumns	of(String name, Column col, String name2, Column col2)

Methods inherited from class java.lang.Object

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

Constructor Detail

MapOfColumnsRowsAndColumns

public MapOfColumnsRowsAndColumns(Map<String,Column> mapOfColumns,
                                  int numRows)

Method Detail

builder

public static MapOfColumnsRowsAndColumns.Builder builder()

of

public static MapOfColumnsRowsAndColumns of(String name,
                                            Column col)

of

public static MapOfColumnsRowsAndColumns of(String name,
                                            Column col,
                                            String name2,
                                            Column col2)

fromMap

public static MapOfColumnsRowsAndColumns fromMap(Map<String,? extends Column> map)

fromResultRow

public static MapOfColumnsRowsAndColumns fromResultRow(ArrayList<ResultRow> objs,
                                                       RowSignature signature)

fromRowObjects

public static MapOfColumnsRowsAndColumns fromRowObjects(Object[][] objs,
                                                        RowSignature signature)

getColumnNames

public Set<String> getColumnNames()

Description copied from interface: RowsAndColumns

The set of column names available from the RowsAndColumns

Specified by:

getColumnNames in interface RowsAndColumns

Returns:

The set of column names available from the RowsAndColumns

numRows

public int numRows()

Description copied from interface: RowsAndColumns

The number of rows in the RowsAndColumns object

Specified by:

numRows in interface RowsAndColumns

Returns:

the integer number of rows

findColumn

public Column findColumn(String name)

Description copied from interface: RowsAndColumns

Finds a column by name. null is returned if the column is not found. The RowsAndColumns object should not attempt to default not-found columns to pretend as if they exist, instead the user of the RowsAndColumns object should decide the correct semantic interpretation of a column that does not exist. It is expected that most locations will choose to believe that the column does exist and is always null, but there are often optimizations that can effect this same assumption without doing a lot of extra work if the calling code knows that it does not exist.

Specified by:

findColumn in interface RowsAndColumns

Parameters:

name - the name of the column to find

Returns:

the Column, if found. null if not found.

as

public <T> T as(Class<T> clazz)

Description copied from interface: RowsAndColumns

Asks the RowsAndColumns to return itself as a concrete implementation of a specific interface. The interface asked for will tend to be a semantically-meaningful interface. This method allows the calling code to interrogate the RowsAndColumns object about whether it can offer a meaningful optimization of the semantic interface. If a RowsAndColumns cannot do anything specifically optimal for the interface requested, it should return null instead of trying to come up with its own default implementation.

Specified by:

as in interface RowsAndColumns

Type Parameters:

T - The interface that the calling code wants a concrete implementation of

Parameters:

clazz - A class object representing the interface that the calling code wants a concrete implementation of

Returns:

A concrete implementation of the interface, or null if there is no meaningful optimization to be had through a local implementation of the interface.