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

Java Enums (?? ? ??)? ?? ??? ???? ? ???? ?? ??? ?????. ??? ??? ???? ???? ???? ?? ??? ????? ?? ? ? ??? ???? ? ?? ?????. ???? ??? ???? ?? ? ? ??? ???? ??? ??? ????.

1. ?? ?? :
   ??? ???? enum ??? ?? ?? ??? ?? ??? ??? ?? ??????. ??? ??? ???? ??? ??? ????.

    <code class="java">public enum Day { SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY }</code>

2. ?? ?? :
   ??? ??, ??? ?? ? ?? ??? ???? ??? ? ????. ?? ??:

    <code class="java">Day today = Day.MONDAY;</code>

   == ???? ???? ?? ?? ??? ?? ????.

    <code class="java">if (today == Day.MONDAY) { System.out.println("It's Monday!"); }</code>

3. ?? ??? ? ?? :
   ??? ??? ???? ???? ? ? ??? ?? ???? ??? ? ????. ?? ??, ?? ?? ?? ?????? ?? :

    <code class="java">public enum Day { SUNDAY(1), MONDAY(2), TUESDAY(3), WEDNESDAY(4), THURSDAY(5), FRIDAY(6), SATURDAY(7); private final int dayNumber; Day(int dayNumber) { this.dayNumber = dayNumber; } public int getDayNumber() { return dayNumber; } }</code>

   Getter ??? ?? ??? ??? ??? ? ? ????.

    <code class="java">Day today = Day.MONDAY; int dayNumber = today.getDayNumber(); // Returns 2</code>

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

Java?? ??? ???? ?? ? ? ??? ???? ? ?? ??? ??? ????.

1. ?? ?? :
   ??? ??? ? ? ??? ? ????? ?? ??? ???? ? ??????. ????? ???? ???? ??? ??? ?? ???? ?? ?? ???? ??? ??? ??? ??? ?????. ?? ??, ?? ??? Day.SUN ?? ?? ??????? ??? ??? ?????.
2. ??? ? ?? ??? :
   ??? ??? ???? ??? ???? ????? ?? ?? ?? ?? ? ? ????????. ??? ?? ??? (??? ??? ??)? ??? ? ?? ???? ? ??????.
3. ??:
   ??? ?? ??? ?? ????? ??? ???? ? ?????, ?? ??? ?? ??? ??????.
4. ?? ?? :
   ??? ? ? ??? ???? ???, ?? ? ??? ??? ? ????. ?? ?? ??? ??? ????? ??? ?? ???? ?? ??? ?? ? ? ????.
5. Java ???? ?? :
   ??? ??? ?? ??? ? ??? ???, ??? ?? ???? ????? Java ?? ???? ???? Java ?????? ??? ??????.

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

Java?? ??? ??? ??? ???? ?? ???? ??? ?? ???? ? ????. ??? ? ??? ??? ??? ????.

1. ?? ?? :
   ?? ?? ??? ?? ???? ?? ? ? ????. ? ??? ?? ?? ??? ?????. ?? ??, ??? ???? ???? ???? ?? ? ? ????.

    <code class="java">public enum Day { SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY; public boolean isWeekend() { return this == SUNDAY || this == SATURDAY; } }</code>

   ? ??? ??? ?? ??? ? ????.

    <code class="java">Day today = Day.SUNDAY; if (today.isWeekend()) { System.out.println("It's a weekend!"); }</code>

2. ?? ?? :
   ?? ?? ??? ?? ??? ?? ? ? ???, ? ? ??? ?? ??? ????? ?????. ? ??? ?? ? ??? ??? ??? ????.

    <code class="java">public enum Day { SUNDAY { public String getDescription() { return "A day for resting and relaxing."; } }, MONDAY { public String getDescription() { return "The start of the work week."; } }, // Similar implementations for other days... public abstract String getDescription(); }</code>

   ?? ??? ???? ??? ???? ?? ? ? ????.

    <code class="java">Day today = Day.MONDAY; System.out.println(today.getDescription()); // Prints: "The start of the work week."</code>

Java? ??? ??? ?? ??? ? ????. ???? ????

?, Java? ??? ??? ?? ??? ? ???, ?? IF-ELSE ??? ???? ?? ?????? ?? ?? ???? ??? ??? ? ????. ??? ??? ??? ???? ??? ??? ????.

1. ?? ??? ??? :
   ??? ????? ?? ?? ?? ??? ? ????. ?? ??, ??? Day ??? ???? ??? ????.

    <code class="java">Day today = Day.MONDAY; switch (today) { case MONDAY: System.out.println("Start of the work week."); break; case FRIDAY: System.out.println("End of the work week."); break; case SATURDAY: case SUNDAY: System.out.println("It's a weekend!"); break; default: System.out.println("Midweek day."); }</code>

2. ??? ??? (Java 12) :
   Java 12?? ???? ??? ??? ?????? ??? ??? ???? ??? ???? ??? ? ????. ??? Day Enum? ???? ????.

    <code class="java">Day today = Day.MONDAY; String message = switch (today) { case MONDAY -> "Start of the work week."; case FRIDAY -> "End of the work week."; case SATURDAY, SUNDAY -> "It's a weekend!"; default -> "Midweek day."; }; System.out.println(message);</code>

??? ??? ??? ???? ??? ?? ?? ? ??? ?? ??? ??? ??? ? ???? ?? ??? ???? ????.

? ??? Java? ??? ???? ?? ? ? ??? ???? ??? ??????? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!