What is this type of initialization called and why is it used? [duplicate]

问题:

This question already has an answer here:

• Curly braces in “new” expression? (e.g. “new MyClass() { … }”) 2 answers

Animal is a user defined class here.

Animal D = new Animal("Leo") {          @Override public void makeNoise() {                System.out.println("Roar!");         }  };   D.makeNoise(); 

回答1:

Its called an anonymous class and used to define the class and any overridden methods at the same time.

回答2:

That is an anonymous class. For details about anonymous classes and why they are useful, see this tutorial on anonymous classes.

回答3:

This is used to override the initial

Animal.makeNoise() 

method with a custom one for just this instance.

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