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Java????????????????????????????????????????????????????????????????Java???????????????

1. ?????

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public class Outer {    private int id = 10;    private int age = 10;    public void out() {        System.out.println("?????");    }    public class Inner {        private int age = 20; // ?????????????        public void in() {            System.out.println("?????");        }        public void getId() {            System.out.println(id); // 10            System.out.println(Outer.this.age); // 10        }    }}public class Test {    public static void main(String[] args) {        Outer outer = new Outer();        Outer.Inner inner = outer.new Inner();        inner.in(); // ?????        inner.getId(); // 10    }}

2. ?????

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public class Outer {    private int id = 10;    public void out() {        System.out.println("?????");    }    public static class Inner {        public void in() {            System.out.println("?????");        }        public void getId() {            System.out.println(Outer.this.id); // 10        }    }}public class Test {    public static void main(String[] args) {        Outer.Inner inner = new Outer.Inner();        inner.in(); // ?????    }}

3. ?????

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public class Outer {    private int id = 10;    public void method() {        String address = "??"; // ????        class Inner {            public void get() {                System.out.println(id); // ???????????                System.out.println(address); // ??????            }        }        Inner inner = new Inner();        inner.get();    }}public class Test {    public static void main(String[] args) {        Outer outer = new Outer();        outer.method();    }}

4. ?????

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public class Test {    public static void main(String[] args) {        new Apple().eat(); // ???        new UserService() {            @Override            public void hello() {                System.out.println("Hello");            }        }.hello(); // Hello    }}class Apple {    public void eat() {        System.out.println("???");    }}interface UserService {    void hello();}

???????????Java?????????????????????????????????????Java?????????