Volatile method in Java

VolatileMethodsSpec.java

import org.junit.Test;

import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Arrays;

import static org.assertj.core.api.Assertions.assertThat;

public class VolatileMethodsSpec {

    @Test
    public void shouldCreateVolatileMethod() {
        //when
        Method[] methods = Inner.class.getDeclaredMethods();
        //then
        assertThat(
            Arrays
                .stream(methods)
                .filter(m -> m.getName().equals("add"))
                .anyMatch(m -> Modifier.isVolatile(m.getModifiers()))
        ).isTrue();
    }


    private class Inner extends ArrayList<String>{

        /*
        This method creates two methods - one regular, for add(String)
        and one volatile for add(Object), because you could assign Inner to List<?>,
        and List would have add(Object) method. Generics, huh? Pretty fucked up, isn't it?
         */
        @Override
        public boolean add(String s) {
            return true;
        }
    }
}