匿名类问题 [英] Anonymous class question

问题描述

我对此行有点怀疑：

匿名类无法定义构造函数

An anonymous class cannot define a constructor

那么，为什么我们也可以使用以下语法定义一个Anonymous类：

then, why we can also define an Anonymous class with the following syntax:

new class-name ( [ argument-list ] ) { class-body }

推荐答案

您不是在匿名类中定义构造函数，而是从超类调用构造函数。

You are not defining a constructor in anonymous class, you are calling a constructor from superclass.

您无法为匿名类添加正确的构造函数，但是，您可以执行类似的操作。即初始化块。

You can't add a proper constructor for anonymous class, however, you can do something similar. Namely an initialization block.

public class SuperClass {
   public SuperClass(String parameter) {
       // this is called when anonymous class is created
   }
}

// an anonymous class is created and instantiated here
new SuperClass(parameterForSuperClassConstructor) {
   {
      // this code is executed when object is initialized
      // and can be used to do many same things as a constructors
   }

   private void someMethod() {

   }

}

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