Singleton with Enum in Java

MyTest.java

import org.junit.Test;
import static org.junit.Assert.*;

public class MyTest {
    @Test
    public void shouldReturnASDF() {
        assertEquals("asdf", MySingleton.INSTANCE.asdf());
    }

    @Test
    public void shouldReturnQWER() {
        assertEquals("qwer", MySingleton.INSTANCE.qwer());
    }
}

enum MySingleton {
    INSTANCE;
    private String asdf;
    private String qwer;

    MySingleton(){
        asdf = "asdf";
        qwer = "qwer";
    }

    public String asdf(){
        return asdf;
    }

    public String qwer(){
        return qwer;
    }
    
    @Test
    public void myTest() {
        assertEquals("asdf", MySingleton.INSTANCE.asdf());
    }
}