Reflection.java

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import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.stream.Stream;
 
public class Reflection {
 
    public interface Animal {
 
        default String eat() {
            return this.getClass().getSimpleName()
                    + " eats like an ordinary animal";
        }
 
        default String sleep() {
            return this.getClass().getSimpleName()
                    + " sleeps like an ordinary animal";
        }
 
        String go();
    }
 
    public static class Dog implements Animal {
 
        @Override
        public String go() {
            return "Dog walks on four legs";
        }
 
        @Override
        public String sleep() {
            return "Dog sleeps";
        }
    }
 
    public static void main(final String[] args) throws NoSuchMethodException {
        Dog dog = new Dog();
        Stream.of(Dog.class.getMethod("eat"), Dog.class.getMethod("go"), Dog.class.getMethod("sleep"))
                .forEach((m) -> {
                    System.out.println("Method name:   " + m.getName());
                    System.out.println("    isDefault: " + m.isDefault());
                    System.out.print("    invoke:    ");
                    try {
                        m.invoke(dog);
                    } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException ex) {
                    }
                    System.out.println();
                });
    }
}