How to Remove Items from Set based on a Condition in Java - Step by Step Examples

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How to Remove Items from Set based on a Condition in Java ?

Answer

To remove items from a set based on a condition in Java, you can use an iterator and the remove() method.

✐ Examples

1 Remove Even Numbers from a Set

In this example,

First, we create a set of integers named numberSet with values Set numberSet = new HashSet<>(Arrays.asList(1, 2, 3, 4, 5));.
Next, we create an iterator for numberSet.
We iterate through the set using the iterator and check if the current number is even.
If the number is even, we remove it using the remove() method of the iterator.
We print the updated set to verify that even numbers have been removed.

Java Program

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Set<Integer> numberSet = new HashSet<>(Arrays.asList(1, 2, 3, 4, 5));
        System.out.println("Original Set: " + numberSet);
        Iterator<Integer> iterator = numberSet.iterator();
        while (iterator.hasNext()) {
            Integer number = iterator.next();
            if (number % 2 == 0) {
                iterator.remove();
            }
        }
        System.out.println("Set after removing even numbers: " + numberSet);
    }
}

Output

Original Set: [1, 2, 3, 4, 5]
Set after removing even numbers: [1, 3, 5]

2 Remove Strings Longer Than 4 Characters from a Set

In this example,

First, we create a set of strings named stringSet with values Set stringSet = new HashSet<>(Arrays.asList("apple", "banana", "orange", "kiwi"));.
Next, we create an iterator for stringSet.
We iterate through the set using the iterator and check if the length of the current string is greater than 4.
If the length is greater than 4, we remove the string using the remove() method of the iterator.
We print the updated set to verify that strings longer than 4 characters have been removed.

Java Program

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Set<String> stringSet = new HashSet<>(Arrays.asList("apple", "banana", "orange", "kiwi"));
        System.out.println("Original Set: " + stringSet);
        Iterator<String> iterator = stringSet.iterator();
        while (iterator.hasNext()) {
            String str = iterator.next();
            if (str.length() > 4) {
                iterator.remove();
            }
        }
        System.out.println("Set after removing strings longer than 4 characters: " + stringSet);
    }
}

Output

Original Set: [apple, banana, orange, kiwi]
Set after removing strings longer than 4 characters: [kiwi, apple]

Summary

In this tutorial, we learned How to Remove Items from Set based on a Condition in Java language with well detailed examples.

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How to Remove Items from Set based on a Condition in Java - Step by Step Examples

How to Remove Items from Set based on a Condition in Java ?

Answer

✐ Examples

1 Remove Even Numbers from a Set

Java Program

Output

2 Remove Strings Longer Than 4 Characters from a Set

Java Program

Output

Summary

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