假设我有一个使用lambda表达式（闭包）定义的对象列表。有没有一种方法可以检查它们以便进行比较？

我最感兴趣的代码是

    List<Strategy> strategies = getStrategies();
    Strategy a = (Strategy) this::a;
    if (strategies.contains(a)) { // ...

完整的代码是

import java.util.Arrays;
import java.util.List;

public class ClosureEqualsMain {
    interface Strategy {
        void invoke(/*args*/);
        default boolean equals(Object o) { // doesn't compile
            return Closures.equals(this, o);
        }
    }

    public void a() { }
    public void b() { }
    public void c() { }

    public List<Strategy> getStrategies() {
        return Arrays.asList(this::a, this::b, this::c);
    }

    private void testStrategies() {
        List<Strategy> strategies = getStrategies();
        System.out.println(strategies);
        Strategy a = (Strategy) this::a;
        // prints false
        System.out.println("strategies.contains(this::a) is " + strategies.contains(a));
    }

    public static void main(String... ignored) {
        new ClosureEqualsMain().testStrategies();
    }

    enum Closures {;
        public static <Closure> boolean equals(Closure c1, Closure c2) {
            // This doesn't compare the contents 
            // like others immutables e.g. String
            return c1.equals(c2);
        }

        public static <Closure> int hashCode(Closure c) {
            return // a hashCode which can detect duplicates for a Set<Strategy>
        }

        public static <Closure> String asString(Closure c) {
            return // something better than Object.toString();
        }
    }    

    public String toString() {
        return "my-ClosureEqualsMain";
    }
}

似乎唯一的解决方案是将每个lambda定义为一个字段，并且仅使用这些字段。如果要打印出称为的方法，最好使用Method。lambda表达式有更好的方法吗？

此外，是否可以打印lambda并获得人类可读的内容？如果你打印this::a而不是

ClosureEqualsMain$$Lambda$1/821270929@3f99bd52

得到类似的东西

ClosureEqualsMain.a()

甚至使用this.toString和方法。

my-ClosureEqualsMain.a();