考虑这个课程: public class MyClassOfMystery { public static final int NO_FLAGS = ~0; public static final int FIRST_FLAG = 1; public static final int SECOND_FLAG = 1 << 1; public static final int THIRD_FLAG = 1 << 2; public static final int FOURTH_FLAG = 1 << 3; @Retention(RetentionPolicy.SOURCE) @IntDef(flag = true, value = {NO_FLAGS, FIRST_FLAG, SECOND_FLAG, […]