Java for testing syntax highlighting

Main.java

import java.util.Arrays;

public class Main
{
    public static void main(String[] args)
    {
        MyInterface   myInterface   = new ConcreteClass();
        ConcreteClass concreteClass = new ConcreteClass();
        AbstractClass abstractClass = new ConcreteClass();

        myInterface.abstractMethod();
        myInterface.defaultMethod();

        var strings = Arrays.asList(
                Constants.STATIC_FINAL,
                Constants.STATIC,
                Constants.staticMethod(),
                concreteClass.instanceFinal,
                concreteClass.instance,
                concreteClass.abstractMethod());

        int effectivelyFinal = 1;
        int reassigned       = 2;
        reassigned = 3;

        var string = "string";
        var number = 123.456;

        String error       = 1;
        String warning     = "" + concreteClass.toString();
        int    weakWarning = 1000000;
    }

    public interface MyInterface
    {
        String abstractMethod();

        default String defaultMethod()
        {
            return this.toString();
        }
    }

    public abstract static class AbstractClass
            implements MyInterface
    {
    }

    public static class ConcreteClass
            extends AbstractClass
    {
        public final String instanceFinal = "instance";
        public       String instance      = "instance";

        public void setInstance(String instance)
        {
            this.instance = instance;
        }

        @Override
        public String abstractMethod()
        {
            return this.defaultMethod();
        }
    }

    public static class Constants
    {
        public static final String STATIC_FINAL = "constant";
        public static       String STATIC       = "non-constant";

        public static String staticMethod()
        {
            return "";
        }
    }
}