Package org.bsc.langgraph4j.utils

Class CollectionsUtils

java.lang.Object

org.bsc.langgraph4j.utils.CollectionsUtils

public final class CollectionsUtils
extends Object

Utility class for creating collections.

Constructor Summary

Constructors

Constructor	Description
CollectionsUtils()

Method Summary

Modifier and Type	Method	Description
static <K, V> Map.Entry<K,V>	entryOf(K key, V value)	create an entry that accept null value
static <T> Optional<T>	lastMinus(List<T> values, int n)	Returns the value at the specified position from the end of the list, if present.
static <T> Optional<T>	lastOf(List<T> values)	Returns the last value in the list, if present.
static <T> List<T>	listOf(Class<T> clazz)	Deprecated, for removal: This API element is subject to removal in a future version.
static <T> List<T>	listOf(T... objects)	Creates a list containing the provided elements.
static <K, V> Map<K,V>	mapOf()	Creates an empty map.
static <K, V> Map<K,V>	mapOf(K k1, V v1)	Creates a map containing a single key-value pair.
static <K, V> Map<K,V>	mapOf(K k1, V v1, K k2, V v2)	Creates a map containing two key-value pairs.
static <K, V> Map<K,V>	mapOf(K k1, V v1, K k2, V v2, K k3, V v3)	Creates a map containing three key-value pairs.
static <K, V> Map<K,V>	mapOf(K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4)	Creates a map containing three key-value pairs.
static <K, V> Map<K,V>	mapOf(K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4, K k5, V v5)	Creates a map containing three key-value pairs.
static <K, V> Map<K,V>	mergeMap(Map<K,V> map1, Map<K,V> map2)	Merges two maps into a new map, doesn't accept duplicates.
static <K, V> Map<K,V>	mergeMap(Map<K,V> map1, Map<K,V> map2, BinaryOperator<V> mergeFunction)	Merges two maps into a new map, resolving key collisions using the specified merge function.
static String	toString(Collection<?> collection)
static String	toString(Map<?,?> map)

Methods inherited from class java.lang.Object

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

Constructor Details

CollectionsUtils

public CollectionsUtils()

Method Details

toString

public static String toString(Collection<?> collection)

toString

public static String toString(Map<?,?> map)

lastOf

public static <T> Optional<T> lastOf(List<T> values)

Returns the last value in the list, if present.

Returns:

an Optional containing the last value if present, otherwise an empty Optional

lastMinus

public static <T> Optional<T> lastMinus(List<T> values,
 int n)

Returns the value at the specified position from the end of the list, if present.

Parameters:

n - the position from the end of the list

Returns:

an Optional containing the value at the specified position if present, otherwise an empty Optional

mergeMap

public static <K,
V> Map<K,V> mergeMap(Map<K,V> map1,
 Map<K,V> map2)

Merges two maps into a new map, doesn't accept duplicates.

Type Parameters:

K - the type of the keys in the maps

V - the type of the values in the maps

Parameters:

map1 - the first map

map2 - the second map

Returns:

a new map containing all entries from both maps, collisions result in error

Throws:

NullPointerException - if both maps are null

mergeMap

public static <K,
V> Map<K,V> mergeMap(Map<K,V> map1,
 Map<K,V> map2,
 BinaryOperator<V> mergeFunction)

Merges two maps into a new map, resolving key collisions using the specified merge function.

Type Parameters:

K - the type of the keys in the maps

V - the type of the values in the maps

Parameters:

map1 - the first map

map2 - the second map

mergeFunction - the function used to resolve collisions between values associated with the same key

Returns:

a new map containing all entries from both maps, with collisions resolved by the merge function

Throws:

NullPointerException - if both maps are null

entryOf

public static <K,
V> Map.Entry<K,V> entryOf(K key,
 V value)

create an entry that accept null value

Parameters:

key - – the key represented by this entry

value - – the value represented by this entry

Returns:

new entry Type parameters: – the type of the key – the type of the value

listOf

@Deprecated(forRemoval=true)
public static <T> List<T> listOf(Class<T> clazz)

Deprecated, for removal: This API element is subject to removal in a future version.

listOf

@SafeVarargs
public static <T> List<T> listOf(T... objects)

Creates a list containing the provided elements. It allows null values.

Type Parameters:

T - the type of the elements

Parameters:

objects - the elements to be included in the list

Returns:

a list containing the provided elements

mapOf

public static <K,
V> Map<K,V> mapOf()

Creates an empty map. It allows null values.

Type Parameters:

K - the type of the keys

V - the type of the values

Returns:

an empty map

mapOf

public static <K,
V> Map<K,V> mapOf(K k1,
 V v1)

Creates a map containing a single key-value pair. It allows null values.

Type Parameters:

K - the type of the key

V - the type of the value

Parameters:

k1 - the key

v1 - the value

Returns:

an unmodifiable map containing the provided key-value pair

mapOf

public static <K,
V> Map<K,V> mapOf(K k1,
 V v1,
 K k2,
 V v2)

Creates a map containing two key-value pairs. It allows null values.

Type Parameters:

K - the type of the keys

V - the type of the values

Parameters:

k1 - the first key

v1 - the first value

k2 - the second key

v2 - the second value

Returns:

an unmodifiable map containing the provided key-value pairs

mapOf

public static <K,
V> Map<K,V> mapOf(K k1,
 V v1,
 K k2,
 V v2,
 K k3,
 V v3)

Creates a map containing three key-value pairs. It allows null values.

Type Parameters:

K - the type of the keys

V - the type of the values

Parameters:

k1 - the first key

v1 - the first value

k2 - the second key

v2 - the second value

k3 - the third key

v3 - the third value

Returns:

an unmodifiable map containing the provided key-value pairs

mapOf

public static <K,
V> Map<K,V> mapOf(K k1,
 V v1,
 K k2,
 V v2,
 K k3,
 V v3,
 K k4,
 V v4)

Creates a map containing three key-value pairs. It allows null values.

Type Parameters:

K - the type of the keys

V - the type of the values

Parameters:

k1 - the first key

v1 - the first value

k2 - the second key

v2 - the second value

k3 - the third key

v3 - the third value

k4 - the fourth key

v4 - the fourth value@

Returns:

an unmodifiable map containing the provided key-value pairs

mapOf

public static <K,
V> Map<K,V> mapOf(K k1,
 V v1,
 K k2,
 V v2,
 K k3,
 V v3,
 K k4,
 V v4,
 K k5,
 V v5)

Creates a map containing three key-value pairs. It allows null values.

Type Parameters:

K - the type of the keys

V - the type of the values

Parameters:

k1 - the first key

v1 - the first value

k2 - the second key

v2 - the second value

k3 - the third key

v3 - the third value

k4 - the fourth key

v4 - the fourth value@

k5 - the fifth key

v5 - the fifth value@

Returns:

an unmodifiable map containing the provided key-value pairs