所描述的代码提供了c#委托的许多优点。方法，无论是静态的还是动态的，都可以以统一的方式处理。通过反射调用方法的复杂性降低了，而且代码是可重用的，因为在用户代码中不需要额外的类。请注意，我们调用的是invoke的另一个方便版本，其中只带一个参数的方法可以在不创建对象数组的情况下被调用。

  class Class1 {
        public void show(String s) { System.out.println(s); }
    }

    class Class2 {
        public void display(String s) { System.out.println(s); }
    }

    // allows static method as well
    class Class3 {
        public static void staticDisplay(String s) { System.out.println(s); }
    }

    public class TestDelegate  {
        public static final Class[] OUTPUT_ARGS = { String.class };
        public final Delegator DO_SHOW = new Delegator(OUTPUT_ARGS,Void.TYPE);

        public void main(String[] args)  {
            Delegate[] items = new Delegate[3];

            items[0] = DO_SHOW .build(new Class1(),"show,);
            items[1] = DO_SHOW.build (new Class2(),"display");
            items[2] = DO_SHOW.build(Class3.class, "staticDisplay");

            for(int i = 0; i < items.length; i++) {
                items[i].invoke("Hello World");
            }
        }
    }

不，Java没有这个惊人的特性。但是您可以使用观察者模式手动创建它。这里有一个例子: 用java编写c#委托

简短的故事:没有。

Introduction The newest version of the Microsoft Visual J++ development environment supports a language construct called delegates or bound method references. This construct, and the new keywords delegate and multicast introduced to support it, are not a part of the JavaTM programming language, which is specified by the Java Language Specification and amended by the Inner Classes Specification included in the documentation for the JDKTM 1.1 software. It is unlikely that the Java programming language will ever include this construct. Sun already carefully considered adopting it in 1996, to the extent of building and discarding working prototypes. Our conclusion was that bound method references are unnecessary and detrimental to the language. This decision was made in consultation with Borland International, who had previous experience with bound method references in Delphi Object Pascal. We believe bound method references are unnecessary because another design alternative, inner classes, provides equal or superior functionality. In particular, inner classes fully support the requirements of user-interface event handling, and have been used to implement a user-interface API at least as comprehensive as the Windows Foundation Classes. We believe bound method references are harmful because they detract from the simplicity of the Java programming language and the pervasively object-oriented character of the APIs. Bound method references also introduce irregularity into the language syntax and scoping rules. Finally, they dilute the investment in VM technologies because VMs are required to handle additional and disparate types of references and method linkage efficiently.

我知道这篇文章很旧了，但是Java 8增加了lambdas和函数接口的概念，即任何接口都只有一个方法。它们一起提供了与c#委托类似的功能。查看这里获得更多信息，或者只是谷歌Java Lambdas。 http://cr.openjdk.java.net/~briangoetz/lambda/lambda-state-final.html

没有，没有。

你可以通过使用反射来获得你可以调用的Method对象来达到同样的效果，另一种方法是创建一个带有单个“invoke”或“execute”方法的接口，然后实例化它们来调用你感兴趣的方法(即使用匿名内部类)。

你可能还会发现这篇文章很有趣/有用:一个Java程序员看c#委托(@blueskyprojects.com)

虽然它远没有那么干净，但您可以使用Java代理实现c#委托之类的东西。