How to check if a Set is Empty in Java - Step by Step Examples

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How to check if a Set is Empty in Java ?

Answer

To check if a Set is empty in Java, you can use the isEmpty() method provided by the Set interface.

✐ Examples

1 Check if Set is Empty

In this example,

We declare a Set variable named set and initialize it with some elements, or an empty Set if there are no elements.
We use the isEmpty() method on the Set set to determine if it contains any elements.
If the Set is empty, the isEmpty() method returns true; otherwise, it returns false.
We print the result to the standard output to indicate whether the Set is empty or not.

Java Program

import java.util.Set;
import java.util.HashSet;

public class Main {
    public static void main(String[] args) {
        Set<String> set = new HashSet<>(); // Or new HashSet<>() for an empty Set
        boolean isEmpty = set.isEmpty();
        if (isEmpty) {
            System.out.println("The Set is empty");
        } else {
            System.out.println("The Set is not empty");
        }
    }
}

Output

The Set is empty

2 Check if Empty Set is Empty

In this example,

We declare a Set variable named emptySet and initialize it as an empty Set.
We use the isEmpty() method on the Set emptySet to determine if it contains any elements.
Since the Set is empty, the isEmpty() method returns true.
We print the result to the standard output to indicate that the Set is indeed empty.

Java Program

import java.util.Set;
import java.util.HashSet;

public class Main {
    public static void main(String[] args) {
        Set<String> emptySet = new HashSet<>();
        boolean isEmpty = emptySet.isEmpty();
        if (isEmpty) {
            System.out.println("The Set is empty");
        } else {
            System.out.println("The Set is not empty");
        }
    }
}

Output

The Set is empty

Summary

In this tutorial, we learned How to check if a Set is Empty in Java language with well detailed examples.

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How to check if a Set is Empty in Java - Step by Step Examples

How to check if a Set is Empty in Java ?

Answer

✐ Examples

1 Check if Set is Empty

Java Program

Output

2 Check if Empty Set is Empty

Java Program

Output

Summary

More Java Sets Tutorials