interfaces2.java

class Main4 {
    static class Data1 {
        int data = 5;

        int getData() {
            return data;
        }

        void setData(int data) {
            this.data = data;
        }
    }

    static class Data2 {
        int data = 10;

        int acquireData() {
            return data;
        }

        void resetData(int data) {
            this.data = data;
        }
    }

    interface DataInterface<T> {
        int getData(T data);

        void setData(T data, int newData);
    }

    static class Manipulator<T> {

        void manipulate(DataInterface<T> iface, T data) {
            int oldData = iface.getData(data);
            System.out.println(oldData);
            iface.setData(data, oldData + 1);
        }
    }

    public static void main(String[] args) {
        Data1 D1 = new Data1();
        Data2 D2 = new Data2();

        Manipulator<Data1> M1 = new Manipulator<>();
        Manipulator<Data2> M2 = new Manipulator<>();

        DataInterface<Data1> if1 = new DataInterface<Data1>() {

            @Override
            public int getData(Data1 data) {
                return data.getData();
            }

            @Override
            public void setData(Data1 data, int newData) {
                data.setData(newData);
            }

        };

        DataInterface<Data2> if2 = new DataInterface<Data2>() {

            @Override
            public int getData(Data2 data) {
                return data.acquireData();
            }

            @Override
            public void setData(Data2 data, int newData) {
                data.resetData(newData);

            }

        };

        M1.manipulate(if1, D1);
        M2.manipulate(if2, D2);

        M1.manipulate(if1, D1);
        M2.manipulate(if2, D2);

    }
}