How to find Intersection of Two Sets in Java - Step by Step Examples

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How to find Intersection of Two Sets in Java ?

Answer

To find the intersection of two sets in Java, you can use the retainAll method provided by the Set interface.

✐ Examples

1 Find Intersection of Two Sets using retainAll Method

In this example,

We create two sets named set1 and set2.
We call the retainAll method on set1 with set2 as an argument.

Java Program

Set<Integer> set1 = new HashSet<>(Arrays.asList(1, 2, 3, 4, 5));
Set<Integer> set2 = new HashSet<>(Arrays.asList(4, 5, 6, 7, 8));
set1.retainAll(set2);
System.out.println("Intersection: " + set1);

Output

Intersection: [4, 5]

2 Find Intersection of Two Sets using removeAll and addAll Methods

In this example,

We create two sets named set1 and set2.
We remove all elements from set1 that are not in set2, then add all elements from set2 to set1.

Java Program

Set<Integer> set1 = new HashSet<>(Arrays.asList(1, 2, 3, 4, 5));
Set<Integer> set2 = new HashSet<>(Arrays.asList(4, 5, 6, 7, 8));
set1.removeAll(set2);
set1.addAll(set2);
System.out.println("Intersection: " + set1);

Output

Intersection: [4, 5]

Summary

In this tutorial, we learned How to find Intersection of Two Sets in Java language with well detailed examples.

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How to find Intersection of Two Sets in Java - Step by Step Examples

How to find Intersection of Two Sets in Java ?

Answer

✐ Examples

1 Find Intersection of Two Sets using retainAll Method

Java Program

Output

2 Find Intersection of Two Sets using removeAll and addAll Methods

Java Program

Output

Summary

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