refactored tariffloader, added exception checks

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

@@ -4,6 +4,7 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.math.BigDecimal;
 import java.time.LocalDate;
+import java.time.format.DateTimeParseException;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.NavigableMap;
@@ -31,44 +32,49 @@ public final class TariffLoader {
 
         return new TariffConfiguration(animalBaseSums(props), tariffs(props), ageFactors(props),
                 breedFactors(props));
-
     }
 
     private static Map<String, BigDecimal> animalBaseSums(Properties props) {
-
         Map<String, BigDecimal> baseSums = new HashMap<>();
-
         for (String key : props.stringPropertyNames()) {
             if (key.startsWith("baseSum.")) {
                 String animal = key.substring("baseSum.".length()).toUpperCase();
-                BigDecimal baseSum = new BigDecimal(props.getProperty(key));
-                baseSums.put(animal, baseSum);
+                baseSums.put(animal, parseDecimal(key, props.getProperty(key)));
             }
         }
         return baseSums;
     }
 
     private static Map<String, TariffOption> tariffs(Properties props) {
-
         return props.stringPropertyNames().stream().filter(key -> key.startsWith("tariffs."))
                 .map(key -> {
                     String name = key.substring("tariffs.".length()).toUpperCase();
-                    String[] values = props.getProperty(key).split(",");
-                    BigDecimal factor = new BigDecimal(values[0]);
-                    LocalDate availableFrom = LocalDate.parse(values[1]);
+                    String raw = props.getProperty(key);
+                    String[] values = raw.split(",");
+                    if (values.length < 2) {
+                        throw new IllegalStateException("Ungültiges Format für Tarifoption '"
+                                + key + "': erwartet 'Faktor,Datum', gefunden: '" + raw + "'");
+                    }
+                    BigDecimal factor = parseDecimal(key, values[0]);
+                    LocalDate availableFrom = parseDate(key, values[1]);
                     return new TariffOption(name, factor, availableFrom);
                 }).collect(Collectors.toMap(TariffOption::name, tariff -> tariff));
     }
 
     private static NavigableMap<Integer, BigDecimal> ageFactors(Properties props) {
-
         NavigableMap<Integer, BigDecimal> ageFactors = new TreeMap<>();
-
         for (String key : props.stringPropertyNames()) {
             if (key.startsWith("age.")) {
-                Integer age = Integer.parseInt(key.replace("age.", ""));
-                BigDecimal factor = new BigDecimal(props.getProperty(key));
-                ageFactors.put(age, factor);
+                String agePart = key.substring("age.".length());
+                int age;
+                try {
+                    age = Integer.parseInt(agePart);
+                } catch (NumberFormatException e) {
+                    throw new IllegalStateException(
+                            "Ungültiger Alterswert in Schlüssel '" + key + "': '" + agePart + "'",
+                            e);
+                }
+                ageFactors.put(age, parseDecimal(key, props.getProperty(key)));
             }
         }
 
@@ -76,23 +82,38 @@ public final class TariffLoader {
         if (rawElderly == null) {
             throw new IllegalStateException("Pflichtkonfiguration 'elderlyFactor' fehlt.");
         }
-        ageFactors.put(Integer.MAX_VALUE, new BigDecimal(rawElderly));
+        ageFactors.put(Integer.MAX_VALUE, parseDecimal("elderlyFactor", rawElderly));
         return ageFactors;
     }
 
     private static Map<String, BigDecimal> breedFactors(Properties props) {
-
         Map<String, BigDecimal> breedFactors = new HashMap<>();
-
         for (String key : props.stringPropertyNames()) {
             if (key.startsWith("breed.")) {
                 String name = key.substring("breed.".length()).toUpperCase();
-                BigDecimal factor = new BigDecimal(props.getProperty(key));
-                breedFactors.put(name, factor);
+                breedFactors.put(name, parseDecimal(key, props.getProperty(key)));
             }
         }
         return breedFactors;
     }
 
+    private static BigDecimal parseDecimal(String key, String value) {
+        try {
+            return new BigDecimal(value.trim());
+        } catch (NumberFormatException e) {
+            throw new IllegalStateException(
+                    "Ungültiger Zahlenwert für '" + key + "': '" + value + "'", e);
+        }
+    }
+
+    private static LocalDate parseDate(String key, String value) {
+        try {
+            return LocalDate.parse(value.trim());
+        } catch (DateTimeParseException e) {
+            throw new IllegalStateException(
+                    "Ungültiges Datum für '" + key + "': '" + value + "'", e);
+        }
+    }
+
     private TariffLoader() {}
 }