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Solution for Optionals 03 #101

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Solution for Optionals 03 #101

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90dfab3
Solution Optionals 03
SteffenLm Jun 6, 2025
c8a546e
Google Java Format
Jun 6, 2025
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23 changes: 14 additions & 9 deletions Crate.java
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Original file line number Diff line number Diff line change
@@ -1,3 +1,5 @@
import java.util.Optional;

public class Crate<T> {

private T box1;
Expand All @@ -22,18 +24,21 @@ public void insertBottle(T bottle, int box) throws CrateIndexOutOfBoundsExceptio
}
}

public T takeBottle(int box) throws CrateIndexOutOfBoundsException {
public Optional<T> takeBottle(int box) throws CrateIndexOutOfBoundsException {
if (box < 1 || box > 6) {
throw new CrateIndexOutOfBoundsException();
}

return switch (box) {
case 1 -> box1;
case 2 -> box2;
case 3 -> box3;
case 4 -> box4;
case 5 -> box5;
default -> box6;
};
T foundBox =
switch (box) {
case 1 -> box1;
case 2 -> box2;
case 3 -> box3;
case 4 -> box4;
case 5 -> box5;
case 6 -> box6;
default -> null;
};
return Optional.ofNullable(foundBox);
}
}
12 changes: 9 additions & 3 deletions Exercise.java
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Original file line number Diff line number Diff line change
Expand Up @@ -11,9 +11,15 @@ public static void main(String[] args) {
crate.insertBottle(new WineBottle(), 5);
crate.insertBottle(new WineBottle(), 6);

if (crate.takeBottle(3) instanceof BeerBottle beerBottle) {
beerBottle.chugALug();
}
crate
.takeBottle(3)
.ifPresentOrElse(
bottle -> {
if (bottle instanceof BeerBottle beerBottle) {
beerBottle.chugALug();
}
},
() -> System.out.println("Gesuchte Flasche ist nicht vorhanden."));
} catch (CrateIndexOutOfBoundsException e) {
System.err.println(e.getMessage());
}
Expand Down