Package io.deephaven.engine.table.impl

Class SortedColumnsAttribute

java.lang.Object

io.deephaven.engine.table.impl.SortedColumnsAttribute

public class SortedColumnsAttribute
extends Object

Helper class for managing the sorted columns attribute.

Method Summary

Modifier and Type	Method	Description
static Optional<SortingOrder>	getOrderForColumn(Table table, String columnName)	Retrieve the sorting order for a column from a table.
static Optional<SortingOrder>	getOrderForColumn(String attribute, String columnName)	Retrieve the sorting order for a column from an attribute.
static List<SortColumn>	getSortedColumns(Table table)	Get the columns a Table is sorted by.
static boolean	isSortedBy(Table table, String columnName, SortingOrder order)	Determine if a table is sorted by the given column and order.
static void	setOrderForColumn(BaseTable<?> table, String columnName, SortingOrder order)	Mark the table as sorted by the given column.
static String	setOrderForColumn(String attribute, String columnName, SortingOrder order)	Pack the desired sorting order into a String attribute.
static Table	withOrderForColumn(Table table, String columnName, SortingOrder order)	Ensure that the result table is marked as sorted by the given column.
static Table	withOrderForColumn(Table table, String columnName, SortingOrder order, Map<String,?> additionalAttributes)	Ensure that the result table is marked as sorted by the given column.

Methods inherited from class java.lang.Object

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

Method Details

getOrderForColumn

public static Optional<SortingOrder> getOrderForColumn(String attribute,
 String columnName)

Retrieve the sorting order for a column from an attribute.

Parameters:

attribute - the Table's value of Table.SORTED_COLUMNS_ATTRIBUTE.

columnName - the name of the column

Returns:

an optional containing the SortingOrder of the column if defined, empty otherwise

getOrderForColumn

public static Optional<SortingOrder> getOrderForColumn(Table table,
 String columnName)

Retrieve the sorting order for a column from a table.

Parameters:

table - the table to interrogate

columnName - the name of the column

Returns:

an optional containing the SortingOrder of the column if defined, empty otherwise

isSortedBy

public static boolean isSortedBy(Table table,
 String columnName,
 SortingOrder order)

Determine if a table is sorted by the given column and order.

Parameters:

table - the table to interrogate

columnName - the name of the column

order - the order to check for

Returns:

true if table is sorted by columnName in the specified order

setOrderForColumn

public static String setOrderForColumn(String attribute,
 String columnName,
 SortingOrder order)

Pack the desired sorting order into a String attribute.

Parameters:

attribute - an attribute containing sorting order

columnName - the column to update

order - the order that the column is sorted in

Returns:

a String suitable for use as a Table.SORTED_COLUMNS_ATTRIBUTE value.

setOrderForColumn

public static void setOrderForColumn(BaseTable<?> table,
 String columnName,
 SortingOrder order)

Mark the table as sorted by the given column.

Parameters:

table - the table to update

columnName - the column to update

order - the order that the column is sorted in

withOrderForColumn

public static Table withOrderForColumn(Table table,
 String columnName,
 SortingOrder order)

Ensure that the result table is marked as sorted by the given column.

Warning: this method performs no validation. If the column is not actually sorted in the declared order, range and match filters will silently return incorrect (missing or wrong) results with no error or warning. Prefer TableAssertions.assertSorted(io.deephaven.engine.table.Table, java.lang.String, io.deephaven.engine.table.impl.SortingOrder) instead whenever possible — it validates the sort order at call time for static tables and re-validates on every update for refreshing tables. Only use this method when you have an external guarantee that the data is sorted and the validation cost of assertSorted is unacceptable.

Parameters:

table - the table to update

columnName - the column to update

order - the order that the column is sorted in

Returns:

table, or a copy of it with the necessary attribute set

withOrderForColumn

public static Table withOrderForColumn(Table table,
 String columnName,
 SortingOrder order,
 Map<String,?> additionalAttributes)

Ensure that the result table is marked as sorted by the given column.

Warning: this method performs no validation. If the column is not actually sorted in the declared order, range and match filters will silently return incorrect (missing or wrong) results with no error or warning. Prefer TableAssertions.assertSorted(io.deephaven.engine.table.Table, java.lang.String, io.deephaven.engine.table.impl.SortingOrder) instead whenever possible — it validates the sort order at call time for static tables and re-validates on every update for refreshing tables. Only use this method when you have an external guarantee that the data is sorted and the validation cost of assertSorted is unacceptable.

Parameters:

table - the table to update

columnName - the column to update

order - the order that the column is sorted in

Returns:

table, or a copy of it with the necessary attribute set

getSortedColumns

public static List<SortColumn> getSortedColumns(Table table)

Get the columns a Table is sorted by.

Parameters:

table - The table to interrogate

Returns:

A (possibly-empty) list of SortColumns representing columns the table is sorted on and their associated sort order