How to Access Items in a Set in Java - Step by Step Examples

How to Access Items in a Set in Java ?

Answer

To access items in a Set in Java, you can use methods like iterating over the set or using contains to check for item existence.

✐ Examples

1 Iterate Over Items in a Set

In this example,

We create a Set named fruitSet with some initial values.
We use a for-each loop to iterate over each item in the set.
Within the loop, we print each item to the standard output.

Java Program

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

public class Main {
    public static void main(String[] args) {
        Set<String> fruitSet = new HashSet<>();
        fruitSet.add("Apple");
        fruitSet.add("Banana");
        fruitSet.add("Cherry");

        for (String fruit : fruitSet) {
            System.out.println(fruit);
        }
    }
}

Output

Apple
Banana
Cherry

2 Check if Set Contains an Item

In this example,

We create a Set named numberSet with some initial values.
We use the contains method to check if an item exists in the set.
The contains method returns true if the item is in the set, otherwise false.

Java Program

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

public class Main {
    public static void main(String[] args) {
        Set<Integer> numberSet = new HashSet<>();
        numberSet.add(1);
        numberSet.add(2);
        numberSet.add(3);
        numberSet.add(4);
        numberSet.add(5);

        boolean containsThree = numberSet.contains(3);
        System.out.println("Set contains 3: " + containsThree);
    }
}

Output

Set contains 3: true

3 Access Item by Index (Not Directly Supported)

In this example,

In Java, Sets are unordered collections, so direct indexing is not supported.
To access items by index, you can convert the set to a List and then use indexing on the List.

Java Program

import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.ArrayList;

public class Main {
    public static void main(String[] args) {
        Set<String> colorSet = new HashSet<>();
        colorSet.add("Red");
        colorSet.add("Green");
        colorSet.add("Blue");

        List<String> colorList = new ArrayList<>(colorSet);

        String secondColor = colorList.get(1);
        System.out.println("Second color in set: " + secondColor);
    }
}

Output

Second color in set: Green

Summary

In this tutorial, we learned How to Access Items in a Set in Java language with well detailed examples.

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How to Access Items in a Set in Java - Step by Step Examples

How to Access Items in a Set in Java ?

Answer

✐ Examples

1 Iterate Over Items in a Set

Java Program

Output

2 Check if Set Contains an Item

Java Program

Output

3 Access Item by Index (Not Directly Supported)

Java Program

Output

Summary

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