"不能在块内声明接口；接口本身就是静态的"这句话出自https://docs.oracle.com/javase/tutorial/java/javaOO/localclasses.html#local-classes-are-similar-to-inner-classes
但是，我可以在下面的代码中声明一个接口.我还可以通过扩展接口来创建匿名类.
public void testing() {
interface LocalInterface {
void prints();
}
LocalInterface localInterface = new LocalInterface() {
@Override
public void prints() {
System.out.println("hello world");
}};
localInterface.prints();
}
