Class OpenSet

java.lang.Object

cloud.opencode.base.collections.OpenSet

public final class OpenSet
extends Object

OpenSet - Set Facade Utility Class OpenSet - Set 门面工具类

Provides comprehensive set operations including creation, set algebra, filtering, and querying.

提供全面的 Set 操作，包括创建、集合代数、过滤和查询。

Features | 主要功能:

• Factory methods for set creation - Set 创建工厂方法
• Set algebra operations - 集合代数运算
• Set filtering - Set 过滤
• Power set and combinations - 幂集和组合

Usage Examples | 使用示例:

// Create set - 创建 Set
Set<String> set = OpenSet.of("a", "b", "c");

// Union - 并集
SetView<String> union = OpenSet.union(set1, set2);

// Intersection - 交集
SetView<String> intersection = OpenSet.intersection(set1, set2);

// Power set - 幂集
Set<Set<String>> powerSet = OpenSet.powerSet(set);

Performance | 性能特性:

• Most operations: O(n) - 大多数操作: O(n)
• Contains: O(1) for HashSet - 包含: HashSet 为 O(1)
• Power set: O(2^n) - 幂集: O(2^n)

Security | 安全性:

• Thread-safe: No - 线程安全: 否
• Null-safe: Yes - 空值安全: 是

Since:

JDK 25, opencode-base-collections V1.0.0

Author:

Leon Soo www.LeonSoo.com

See Also:

• OpenCode.cloud

Method Summary

Modifier and Type	Method	Description
static <E> SetAlgebra<E>	algebra(Set<E> set)	Get the SetAlgebra interface for the set.
static <E> Set<List<E>>	cartesianProduct(Set<? extends E>... sets)	Compute Cartesian product of sets.
static <E> Set<Set<E>>	combinations(Set<E> set, int size)	Compute combinations of given size.
static <E> SetView<E>	difference(Set<E> set1, Set<?> set2)	Compute difference of two sets as a SetView.
static boolean	disjoint(Set<?> set1, Set<?> set2)	Check if sets are disjoint.
static boolean	equals(Set<?> set1, Set<?> set2)	Check if sets are equal (same elements).
static <E> Set<E>	filter(Set<E> set, Predicate<? super E> predicate)	Filter set by predicate.
static <E> HashSet<E>	from(Iterable<? extends E> elements)	Create a HashSet from an Iterable.
static <E> SetView<E>	intersection(Set<E> set1, Set<?> set2)	Compute intersection of two sets as a SetView.
static boolean	isSubset(Set<?> subset, Set<?> superset)	Check if one set is a subset of another.
static <E> Set<E>	newConcurrentHashSet()	Create a concurrent hash set.
static <E> HashSet<E>	newHashSet()	Create an empty HashSet.
static <E> LinkedHashSet<E>	newLinkedHashSet()	Create an empty LinkedHashSet.
static <E extends Comparable<E>> TreeSet<E>	newTreeSet()	Create an empty TreeSet.
static <E> TreeSet<E>	newTreeSet(Comparator<? super E> comparator)	Create a TreeSet with comparator.
static <E> HashSet<E>	of(E... elements)	Create a HashSet with elements.
static <E> Set<Set<E>>	powerSet(Set<E> set)	Compute power set (all subsets) of a set.
static <E> SetView<E>	symmetricDifference(Set<? extends E> set1, Set<? extends E> set2)	Compute symmetric difference of two sets as a SetView.
static <E> SetView<E>	union(Set<? extends E> set1, Set<? extends E> set2)	Compute union of two sets as a SetView.
static <E> HashSet<E>	withExpectedSize(int expectedSize)	Create a HashSet with expected size.

Methods inherited from class Object

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

Method Details

newHashSet

public static <E> HashSet<E> newHashSet()

Create an empty HashSet. 创建空的 HashSet。

Type Parameters:

E - element type | 元素类型

Returns:

new HashSet | 新的 HashSet

of

@SafeVarargs
public static <E> HashSet<E> of(E... elements)

Create a HashSet with elements. 创建包含元素的 HashSet。

Type Parameters:

E - element type | 元素类型

Parameters:

elements - the elements | 元素

Returns:

new HashSet | 新的 HashSet

from

public static <E> HashSet<E> from(Iterable<? extends E> elements)

Create a HashSet from an Iterable. 从 Iterable 创建 HashSet。

Type Parameters:

E - element type | 元素类型

Parameters:

elements - the elements | 元素

Returns:

new HashSet | 新的 HashSet

withExpectedSize

public static <E> HashSet<E> withExpectedSize(int expectedSize)

Create a HashSet with expected size. 创建具有预期大小的 HashSet。

Type Parameters:

E - element type | 元素类型

Parameters:

expectedSize - expected size | 预期大小

Returns:

new HashSet | 新的 HashSet

newLinkedHashSet

public static <E> LinkedHashSet<E> newLinkedHashSet()

Create an empty LinkedHashSet. 创建空的 LinkedHashSet。

Type Parameters:

E - element type | 元素类型

Returns:

new LinkedHashSet | 新的 LinkedHashSet

newTreeSet

public static <E extends Comparable<E>> TreeSet<E> newTreeSet()

Create an empty TreeSet. 创建空的 TreeSet。

Type Parameters:

E - element type | 元素类型

Returns:

new TreeSet | 新的 TreeSet

newTreeSet

public static <E> TreeSet<E> newTreeSet(Comparator<? super E> comparator)

Create a TreeSet with comparator. 创建具有比较器的 TreeSet。

Type Parameters:

E - element type | 元素类型

Parameters:

comparator - the comparator | 比较器

Returns:

new TreeSet | 新的 TreeSet

newConcurrentHashSet

public static <E> Set<E> newConcurrentHashSet()

Create a concurrent hash set. 创建并发哈希集合。

Type Parameters:

E - element type | 元素类型

Returns:

new concurrent set | 新的并发 Set

union

public static <E> SetView<E> union(Set<? extends E> set1,
 Set<? extends E> set2)

Compute union of two sets as a SetView. 计算两个集合的并集视图。

Type Parameters:

E - element type | 元素类型

Parameters:

set1 - first set | 第一个集合

set2 - second set | 第二个集合

Returns:

union view | 并集视图

intersection

public static <E> SetView<E> intersection(Set<E> set1,
 Set<?> set2)

Compute intersection of two sets as a SetView. 计算两个集合的交集视图。

Type Parameters:

E - element type | 元素类型

Parameters:

set1 - first set | 第一个集合

set2 - second set | 第二个集合

Returns:

intersection view | 交集视图

difference

public static <E> SetView<E> difference(Set<E> set1,
 Set<?> set2)

Compute difference of two sets as a SetView. 计算两个集合的差集视图。

Type Parameters:

E - element type | 元素类型

Parameters:

set1 - first set | 第一个集合

set2 - second set | 第二个集合

Returns:

difference view | 差集视图

symmetricDifference

public static <E> SetView<E> symmetricDifference(Set<? extends E> set1,
 Set<? extends E> set2)

Compute symmetric difference of two sets as a SetView. 计算两个集合的对称差集视图。

Type Parameters:

E - element type | 元素类型

Parameters:

set1 - first set | 第一个集合

set2 - second set | 第二个集合

Returns:

symmetric difference view | 对称差集视图

powerSet

public static <E> Set<Set<E>> powerSet(Set<E> set)

Compute power set (all subsets) of a set. 计算集合的幂集（所有子集）。

Type Parameters:

E - element type | 元素类型

Parameters:

set - the set | 集合

Returns:

power set | 幂集

combinations

public static <E> Set<Set<E>> combinations(Set<E> set,
 int size)

Compute combinations of given size. 计算给定大小的组合。

Type Parameters:

E - element type | 元素类型

Parameters:

set - the set | 集合

size - combination size | 组合大小

Returns:

set of combinations | 组合集合

cartesianProduct

@SafeVarargs
public static <E> Set<List<E>> cartesianProduct(Set<? extends E>... sets)

Compute Cartesian product of sets. 计算集合的笛卡尔积。

Type Parameters:

E - element type | 元素类型

Parameters:

sets - the sets | 集合

Returns:

Cartesian product | 笛卡尔积

filter

public static <E> Set<E> filter(Set<E> set,
 Predicate<? super E> predicate)

Filter set by predicate. 按谓词过滤集合。

Type Parameters:

E - element type | 元素类型

Parameters:

set - the set | 集合

predicate - the predicate | 谓词

Returns:

filtered set | 过滤后的集合

algebra

public static <E> SetAlgebra<E> algebra(Set<E> set)

Get the SetAlgebra interface for the set. 获取集合的 SetAlgebra 接口。

Type Parameters:

E - element type | 元素类型

Parameters:

set - the set | 集合

Returns:

SetAlgebra instance | SetAlgebra 实例

disjoint

public static boolean disjoint(Set<?> set1,
 Set<?> set2)

Check if sets are disjoint. 检查集合是否不相交。

Parameters:

set1 - first set | 第一个集合

set2 - second set | 第二个集合

Returns:

true if disjoint | 如果不相交则返回 true

isSubset

public static boolean isSubset(Set<?> subset,
 Set<?> superset)

Check if one set is a subset of another. 检查一个集合是否为另一个的子集。

Parameters:

subset - potential subset | 潜在子集

superset - potential superset | 潜在超集

Returns:

true if subset | 如果是子集则返回 true

equals

public static boolean equals(Set<?> set1,
 Set<?> set2)

Check if sets are equal (same elements). 检查集合是否相等（相同元素）。

Parameters:

set1 - first set | 第一个集合

set2 - second set | 第二个集合

Returns:

true if equal | 如果相等则返回 true