java：内部类

class A
{
    class B
    {
    }
}

class Test
{
    public static void main(String args[]){
        A a = new A();
        A.B b = new A().new B();　　　　// 或 a.new B();
    }
}

interface A
{
    public void dowork();
}

class B
{
    public void dowork(A a){
        a.dowork();
    }
}

class Test
{
    public static void main(String args[]){
        B b =new B();
        b.dowork(new A(){    
            public void dowork(){
                System.out.println("匿名内部类");
            };
        });
    }
}