org.apache.druid.segment.join.lookup

Class LookupColumnSelectorFactory

java.lang.Object

org.apache.druid.segment.join.lookup.LookupColumnSelectorFactory

All Implemented Interfaces:

ColumnInspector, ColumnSelectorFactory

public class LookupColumnSelectorFactory
extends Object
implements ColumnSelectorFactory

Field Summary

Fields

Modifier and Type	Field and Description
static String	KEY_COLUMN
static String	VALUE_COLUMN

Method Summary

Modifier and Type	Method and Description
ColumnCapabilities	getColumnCapabilities(String column) Returns capabilities of a particular column, if known.
ColumnValueSelector	makeColumnValueSelector(String columnName) Returns ColumnValueSelector corresponding to the given column name, or NilColumnValueSelector if the column with such name is absent.
DimensionSelector	makeDimensionSelector(DimensionSpec dimensionSpec)

Methods inherited from class java.lang.Object

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

Field Detail

KEY_COLUMN

public static final String KEY_COLUMN

See Also:

Constant Field Values

VALUE_COLUMN

public static final String VALUE_COLUMN

See Also:

Constant Field Values

Method Detail

makeDimensionSelector

@Nonnull
public DimensionSelector makeDimensionSelector(DimensionSpec dimensionSpec)

Specified by:

makeDimensionSelector in interface ColumnSelectorFactory

makeColumnValueSelector

@Nonnull
public ColumnValueSelector makeColumnValueSelector(String columnName)

Description copied from interface: ColumnSelectorFactory

Returns ColumnValueSelector corresponding to the given column name, or NilColumnValueSelector if the column with such name is absent.

Specified by:

makeColumnValueSelector in interface ColumnSelectorFactory

getColumnCapabilities

@Nullable
public ColumnCapabilities getColumnCapabilities(String column)

Description copied from interface: ColumnSelectorFactory

Returns capabilities of a particular column, if known. May be null if the column doesn't exist, or if the column does exist but the capabilities are unknown. The latter is possible with dynamically discovered columns.

Specified by:

getColumnCapabilities in interface ColumnInspector

Specified by:

getColumnCapabilities in interface ColumnSelectorFactory

Parameters:

column - column name

Returns:

capabilities, or null