Java Guava Sets intersection()用法及代碼示例

Guava 的Sets.intersection()返回兩個集合的交集的不可更改的視圖。返回的集合包含兩個後備集合都包含的所有元素。返回的集合的迭代順序與set1的迭代順序匹配。

用法:

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

返回值：此方法返回兩個集合的交集的不可修改的視圖。

以下示例說明了Sets相交方法的用法方式：

範例1：

// Java code to show implementation 
// of Guava's Sets.intersection() method 
  
import com.google.common.collect.Sets; 
import java.util.Set; 
  
class GFG { 
  
    // Driver's code 
    public static void main(String[] args) 
    { 
        // Creating first set 
        Set<Integer> 
            set1 = Sets.newHashSet(10, 20, 30, 40, 50); 
  
        // Creating second set 
        Set<Integer> 
            set2 = Sets.newHashSet(30, 50, 70, 90); 
  
        // Using Guava's Sets.intersection() method 
        Set<Integer> 
            answer = Sets.intersection(set1, set2); 
  
        // Displaying the intersection of set1 and set2 
        System.out.println("Set 1:"
                           + set1); 
        System.out.println("Set 2:"
                           + set2); 
        System.out.println("Set 1 intersection Set 2:"
                           + answer); 
    } 
}

輸出：

Set 1:[40, 10, 50, 20, 30]
Set 2:[50, 90, 30, 70]
Set 1 intersection Set 2:[50, 30]

範例2：

// Java code to show implementation 
// of Guava's Sets.intersection() method 
  
import com.google.common.collect.Sets; 
import java.util.Set; 
  
class GFG { 
  
    // Driver's code 
    public static void main(String[] args) 
    { 
        // Creating first set 
        Set<String> 
            set1 = Sets.newHashSet("G", "e", "e", "k", "s"); 
  
        // Creating second set 
        Set<String> 
            set2 = Sets.newHashSet("g", "f", "G", "e"); 
  
        // Using Guava's Sets.intersection() method 
        Set<String> 
            answer = Sets.intersection(set1, set2); 
  
        // Displaying the intersection of set1 and set2 
        System.out.println("Set 1:"
                           + set1); 
        System.out.println("Set 2:"
                           + set2); 
        System.out.println("Set 1 intersection Set 2:"
                           + answer); 
    } 
}

輸出：

Set 1:[k, s, e, G]
Set 2:[e, f, g, G]
Set 1 intersection Set 2:[e, G]

注意：當set1是兩個集合中的較小者時，返回的視圖的性能會稍好一些。如果您有理由相信其中一個集合通常會小於另一個集合，請先通過。

相關用法

注：本文由純淨天空篩選整理自Sahil_Bansall大神的英文原創作品 Sets intersection() function | Guava | Java。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。