added solution with tariff options as enum and map

src/main/java/com/pfefferminzia/petinsurance/tariffs/AgeTariff.java

@@ -0,0 +1,27 @@
+package com.pfefferminzia.petinsurance.tariffs;
+
+import java.math.BigDecimal;
+
+public enum AgeTariff {
+    UP_TO_TWO(2, new BigDecimal("0.2")), UP_TO_FIVE(5, new BigDecimal("0.25")), UP_TO_SEVEN(7,
+            new BigDecimal("0.28")), OVER_SEVEN(Integer.MAX_VALUE, new BigDecimal("0.3"));
+
+    private final int maxAge;
+
+    private final BigDecimal factor;
+
+    private AgeTariff(int maxAge, BigDecimal factor) {
+        this.maxAge = maxAge;
+        this.factor = factor;
+    }
+
+    public static BigDecimal getFactorForAge(int age) {
+        for (AgeTariff rate : values()) {
+            if (age <= rate.maxAge) {
+                return rate.factor;
+            }
+        }
+        throw new AssertionError("Unexpected age: " + age);
+    }
+
+}

src/main/java/com/pfefferminzia/petinsurance/tariffs/BreedPremiumAdjustment.java

@@ -0,0 +1,18 @@
+package com.pfefferminzia.petinsurance.tariffs;
+
+import java.math.BigDecimal;
+import java.util.Map;
+
+public final class BreedPremiumAdjustment {
+    
+    private static final Map<String, BigDecimal> ADJUSTMENTS = Map.of(
+        "Dackel", new BigDecimal("-0.1"),
+        "Bernhardiner", new BigDecimal("0.1")
+    );
+
+    public static BigDecimal forBreed(String breed) {
+        return ADJUSTMENTS.getOrDefault(breed, BigDecimal.ZERO);
+    }
+
+    private BreedPremiumAdjustment() {}
+}

src/main/java/com/pfefferminzia/petinsurance/tariffs/Tariff.java

@@ -3,7 +3,7 @@ package com.pfefferminzia.petinsurance.tariffs;
 import java.math.BigDecimal;
 
 public enum Tariff {
-    KOMPAKT(BigDecimal.ONE), OPTIMAL(BigDecimal.valueOf(1.2)), PREMIUM(BigDecimal.valueOf(1.4));
+    KOMPAKT(BigDecimal.ONE), OPTIMAL(new BigDecimal("1.2")), PREMIUM(new BigDecimal("1.4"));
 
     private final BigDecimal rate;