如何获取方法的引用？

import java.lang.reflect.Method;

public class ReflectionExample {
    public static void main(String[] args) {
        try {
            Class<?> clazz = Class.forName("com.example.MyClass");
            Method method = clazz.getMethod("myMethod", String.class);
            method.invoke(clazz.newInstance(), "Hello, World!");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

import java.util.function.Function;

public class MethodReferenceExample {
    public static void main(String[] args) {
        Function<String, Integer> lengthFunction = String::length;
        int length = lengthFunction.apply("Hello, World!");
        System.out.println(length);
    }
}