Java Array to Set

In this post, we will learn java array to set conversion.
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There are many ways to convert array to set.

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1. Using Java 8’s Stream

If you are using Java 8, I would recommend using Java 8 Stream.

package org.arpit.java2blog;

import java.util.Arrays;
import java.util.Set;
import java.util.stream.Collectors;

public class ArrayToSetMain {

    public static void main(String[] args) {

        String s[]= {"John","Martin","Mary","John","Martin"};

        Set<String> set = Arrays.stream(s).collect(Collectors.toSet());
        System.out.println(set);
    }
}

Output

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2. Using HashSet constructor()

We can directly call HashSet‘s constructor for java set to array conversion.

package org.arpit.java2blog;

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

public class ArrayToSetMain {

    public static void main(String[] args) {

        String s[]= {"John","Martin","Mary","John","Martin"};

        Set<String> set = new HashSet<>(Arrays.asList(s));;
        System.out.println(set);
    }
}

Output

3. Using Google Guava()

We can use google guava library to do Array to Set conversion using Sets’s newHashSet method.

package org.arpit.java2blog;

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
import org.apache.commons.compress.utils.Sets;

public class ArrayToSetMain {

    public static void main(String[] args) {

        String s[]= {"John","Martin","Mary","John","Martin"};

        Set<String> set = Sets.newHashSet(s);
        System.out.println(set);
    }
}   

Output

That’s all about Java Array to set conversion.