List

This extension provides capability to generate and manipulate list data objects.

Features

• collect (Aggregate Function)

  Collects multiple values to construct a list.

• merge (Aggregate Function)

  Collects multiple lists to merge as a single list.

• add (Function)

  Function returns the updated list after adding the given value.

• addAll (Function)

  Function returns the updated list after adding all the values from the given list.

• clear (Function)

  Function returns the cleared list.

• clone (Function)

  Function returns the cloned list.

• contains (Function)

  Function checks whether the list contains the specific value.

• containsAll (Function)

  Function checks whether the list contains all the values in the given list.

• create (Function)

  Function creates a list containing all values provided.

• get (Function)

  Function returns the value at the specific index, null if index is out of range.

• indexOf (Function)

  Function returns the last index of the given element.

• isEmpty (Function)

  Function checks if the list is empty.

• isList (Function)

  Function checks if the object is type of a list.

• lastIndexOf (Function)

  Function returns the index of the given value.

• remove (Function)

  Function returns the updated list after removing the element with the specified value.

• removeAll (Function)

  Function returns the updated list after removing all the element with the specified list.

• removeByIndex (Function)

  Function returns the updated list after removing the element with the specified index.

• retainAll (Function)

  Function returns the updated list after retaining all the elements in the specified list.

• setValue (Function)

  Function returns the updated list after replacing the element in the given index by the given value.

• size (Function)

  Function to return the size of the list.

• sort (Function)

  Function returns lists sorted in ascending or descending order.

• tokenize (StreamProcessor)

  Tokenize the list and return each key, value as new attributes in events

collect

Collects multiple values to construct a list.

Syntax

<OBJECT> list:collect(<OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value)
<OBJECT> list:collect(<OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value, <BOOL> is.distinct)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
value	Value of the list element		OBJECT INT LONG FLOAT DOUBLE BOOL STRING	No	Yes
is.distinct	If true only distinct elements are collected	false	BOOL	Yes	Yes

Examples EXAMPLE 1

insert into OutputStream
select list:collect(symbol) as stockSymbols
from StockStream#window.lengthBatch(10);

For the window expiry of 10 events, the collect() function will collect attributes of symbol to a single list and return as stockSymbols.

merge

Collects multiple lists to merge as a single list.

Syntax

<OBJECT> list:merge(<OBJECT> list)
<OBJECT> list:merge(<OBJECT> list, <BOOL> is.distinct)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	List to be merged		OBJECT	No	Yes
is.distinct	Whether to return list with distinct values	false	BOOL	Yes	Yes

Examples EXAMPLE 1

insert into OutputStream
select list:merge(list) as stockSymbols
from StockStream#window.lengthBatch(2);

For the window expiry of 2 events, the merge() function will collect attributes of list and merge them to a single list, returned as stockSymbols.

add

Function returns the updated list after adding the given value.

Syntax

<OBJECT> list:add(<OBJECT> list, <OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value)
<OBJECT> list:add(<OBJECT> list, <OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value, <INT> index)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list to which the value should be added.		OBJECT	No	Yes
value	The value to be added.		OBJECT INT LONG FLOAT DOUBLE BOOL STRING	No	Yes
index	The index in which the value should to be added.	last	INT	Yes	Yes

Examples EXAMPLE 1

list:add(stockSymbols, 'IBM')

Function returns the updated list after adding the value IBM in the last index.

EXAMPLE 2

list:add(stockSymbols, 'IBM', 0)

Function returns the updated list after adding the value IBM in the 0th index.

addAll

Function returns the updated list after adding all the values from the given list.

Syntax

<OBJECT> list:addAll(<OBJECT> to.list, <OBJECT> from.list)
<OBJECT> list:addAll(<OBJECT> to.list, <OBJECT> from.list, <BOOL> is.distinct)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
to.list	The list into which the values need to copied.		OBJECT	No	Yes
from.list	The list from which the values are copied.		OBJECT	No	Yes
is.distinct	If true returns list with distinct values	false	BOOL	Yes	Yes

Examples EXAMPLE 1

list:putAll(toList, fromList)

If toList contains values ('IBM', 'GDN'), and if fromList contains values ('IBM', 'XYZ') then the function returns updated toList with values ('IBM', 'GDN', 'IBM', 'XYZ').

EXAMPLE 2

list:putAll(toList, fromList, true)

If toList contains values ('IBM', 'GDN'), and if fromList contains values ('IBM', 'XYZ') then the function returns updated toList with values ('IBM', 'GDN', 'XYZ').

clear

Function returns the cleared list.

Syntax

<OBJECT> list:clear(<OBJECT> list)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list which needs to be cleared		OBJECT	No	Yes

Examples EXAMPLE 1

list:clear(stockDetails)

Returns an empty list.

clone

Function returns the cloned list.

Syntax

<OBJECT> list:clone(<OBJECT> list)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list to which needs to be cloned.		OBJECT	No	Yes

Examples EXAMPLE 1

list:clone(stockSymbols)

Function returns cloned list of stockSymbols.

contains

Function checks whether the list contains the specific value.

Syntax

<BOOL> list:contains(<OBJECT> list, <OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list that needs to be checked on whether it contains the value or not.		OBJECT	No	Yes
value	The value that needs to be checked.		OBJECT INT LONG FLOAT DOUBLE BOOL STRING	No	Yes

Examples EXAMPLE 1

list:contains(stockSymbols, 'IBM')

Returns true if the stockSymbols list contains value IBM else it returns false.

containsAll

Function checks whether the list contains all the values in the given list.

Syntax

<BOOL> list:containsAll(<OBJECT> list, <OBJECT> given.list)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list that needs to be checked on whether it contains all the values or not.		OBJECT	No	Yes
given.list	The list which contains all the values to be checked.		OBJECT	No	Yes

Examples EXAMPLE 1

list:containsAll(stockSymbols, latestStockSymbols)

Returns true if the stockSymbols list contains values in latestStockSymbols else it returns false.

create

Function creates a list containing all values provided.

Syntax

<OBJECT> list:create()
<OBJECT> list:create(<OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value1)
<OBJECT> list:create(<OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value1, <OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> ...)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
value1	Value 1		OBJECT INT LONG FLOAT DOUBLE BOOL STRING	Yes	Yes

Examples EXAMPLE 1

list:create(1, 2, 3, 4, 5, 6)

This returns a list with values 1, 2, 3, 4, 5 and 6.

EXAMPLE 2

list:create()

This returns an empty list.

get

Function returns the value at the specific index, null if index is out of range.

Syntax

<OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> list:get(<OBJECT> list, <INT> index)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	Attribute containing the list		OBJECT	No	Yes
index	Index of the element		INT	No	Yes

Examples EXAMPLE 1

list:get(stockSymbols, 1)

This returns the element in the 1st index in the stockSymbols list.

indexOf

Function returns the last index of the given element.

Syntax

<INT> list:indexOf(<OBJECT> list, <OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list to be checked to get index of an element.		OBJECT	No	Yes
value	Value for which last index needs to be identified.		OBJECT INT LONG FLOAT DOUBLE BOOL STRING	No	Yes

Examples EXAMPLE 1

list:indexOf(stockSymbols. `IBM`)

Returns the last index of the element IBM if present else it returns -1.

isEmpty

Function checks if the list is empty.

Syntax

<BOOL> list:isEmpty(<OBJECT> list)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list that needs to be checked whether it's empty or not.		OBJECT	No	Yes

Examples EXAMPLE 1

list:isEmpty(stockSymbols)

Returns true if the stockSymbols list is empty else it returns false.

isList

Function checks if the object is type of a list.

Syntax

<BOOL> list:isList(<OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> arg)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
arg	The argument the need to be determined whether it's a list or not.		OBJECT INT LONG FLOAT DOUBLE BOOL STRING	No	Yes

Examples EXAMPLE 1

list:isList(stockSymbols)

Returns true if the stockSymbols is and an instance of java.util.List else it returns false.

lastIndexOf

Function returns the index of the given value.

Syntax

<INT> list:lastIndexOf(<OBJECT> list, <OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list to be checked to get index of an element.		OBJECT	No	Yes
value	Value for which last index needs to be identified.		OBJECT INT LONG FLOAT DOUBLE BOOL STRING	No	Yes

Examples EXAMPLE 1

list:lastIndexOf(stockSymbols. `IBM`)

Returns the last index of the element IBM if present else it returns -1.

remove

Function returns the updated list after removing the element with the specified value.

Syntax

<OBJECT> list:remove(<OBJECT> list, <OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list that needs to be updated.		OBJECT	No	Yes
value	The value of the element that needs to removed.		OBJECT INT LONG FLOAT DOUBLE BOOL STRING	No	Yes

Examples EXAMPLE 1

list:remove(stockSymbols, 'IBM')

This returns the updated list, stockSymbols after stockSymbols the value IBM.

removeAll

Function returns the updated list after removing all the element with the specified list.

Syntax

<OBJECT> list:removeAll(<OBJECT> list, <OBJECT> given.list)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list that needs to be updated.		OBJECT	No	Yes
given.list	The list with all the elements that needs to removed.		OBJECT	No	Yes

Examples EXAMPLE 1

list:removeAll(stockSymbols, latestStockSymbols)

This returns the updated list, stockSymbols after removing all the values in latestStockSymbols.

removeByIndex

Function returns the updated list after removing the element with the specified index.

Syntax

<OBJECT> list:removeByIndex(<OBJECT> list, <INT> index)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list that needs to be updated.		OBJECT	No	Yes
index	The index of the element that needs to removed.		INT	No	Yes

Examples EXAMPLE 1

list:removeByIndex(stockSymbols, 0)

This returns the updated list, stockSymbols after removing value at 0 th index.

retainAll

Function returns the updated list after retaining all the elements in the specified list.

Syntax

<OBJECT> list:retainAll(<OBJECT> list, <OBJECT> given.list)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list that needs to be updated.		OBJECT	No	Yes
given.list	The list with all the elements that needs to reatined.		OBJECT	No	Yes

Examples EXAMPLE 1

list:retainAll(stockSymbols, latestStockSymbols)

This returns the updated list, stockSymbols after retaining all the values in latestStockSymbols.

setValue

Function returns the updated list after replacing the element in the given index by the given value.

Syntax

<OBJECT> list:setValue(<OBJECT> list, <INT> index, <OBJECT|INT|LONG|FLOAT|DOUBLE|BOOL|STRING> value)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list to which the value should be updated.		OBJECT	No	Yes
index	The index in which the value should to be updated.		INT	No	Yes
value	The value to be updated with.		OBJECT INT LONG FLOAT DOUBLE BOOL STRING	No	Yes

Examples EXAMPLE 1

list:set(stockSymbols, 0, 'IBM')

Function returns the updated list after replacing the value at 0th index with the value IBM

size

Function to return the size of the list.

Syntax

<INT> list:size(<OBJECT> list)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list for which size should be returned.		OBJECT	No	Yes

Examples EXAMPLE 1

list:size(stockSymbols)

Returns size of the stockSymbols list.

sort

Function returns lists sorted in ascending or descending order.

Syntax

<OBJECT> list:sort(<OBJECT> list)
<OBJECT> list:sort(<OBJECT> list, <STRING> order)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	The list which should be sorted.		OBJECT	No	Yes
order	Order in which the list needs to be sorted (ASC/DESC/REV).	REV	STRING	Yes	No

Examples EXAMPLE 1

list:sort(stockSymbols)

Function returns the sorted list in ascending order.

EXAMPLE 2

list:sort(stockSymbols, 'DESC')

Function returns the sorted list in descending order.

tokenize

Tokenize the list and return each key, value as new attributes in events

Syntax

list:tokenize(<OBJECT> list)
list:tokenize(<OBJECT> list, <OBJECT> ...)

QUERY PARAMETERS

Name	Description	Default Value	Possible Data Types	Optional	Dynamic
list	Array list which needs to be tokenized		OBJECT	No	Yes

Extra Return Attributes

Name	Description	Possible Types
index	Index of an entry consisted in the list	INT
value	Value of an entry consisted in the list	OBJECT

Examples EXAMPLE 1

list:tokenize(customList)

If custom list contains ('GDN', 'IBM', 'XYZ') elements, then tokenize function will return 3 events with value attributes GDN, IBM and XYZ respectively.