Converted CurrencySet from Java to Kotlin

src/de/banananetwork/dsa/currencies/CurrencySet.java

@@ -1,40 +0,0 @@
-package de.banananetwork.dsa.currencies;
-
-import java.util.*;
-
-public class CurrencySet {
-
-	private final Currency[] currencies;
-
-	private CurrencySet(Currency[] currencies) {
-		this.currencies = currencies;
-	}
-
-	public Map<Currency, Integer> transferToSet(int baseValue) {
-		final Map<Currency, Integer> values = new EnumMap<>(Currency.class);
-		for (Currency currency : currencies) {
-			int value = currency.transferTo(baseValue);
-			values.put(currency, value);
-			baseValue -= currency.transferFrom(value);
-		}
-		if (baseValue != 0)
-			throw new RuntimeException(); // TODO Change to ValueNotRepresentableException
-		return values;
-	}
-
-	public static class Builder {
-
-		private List<Currency> currencies = new LinkedList<>();
-
-		public Builder add(Currency currency) {
-			this.currencies.add(currency);
-			return this;
-		}
-
-		public CurrencySet create() {
-			return new CurrencySet(currencies.stream().sorted(Comparator.comparing(Currency::getMultiplier).reversed()).toArray(Currency[]::new));
-		}
-
-	}
-
-}

src/de/banananetwork/dsa/currencies/CurrencySet.kt

@@ -0,0 +1,37 @@
+package de.banananetwork.dsa.currencies
+
+import java.util.*
+import kotlin.collections.ArrayList
+
+class CurrencySet private constructor(private val currencies: Array<Currency>) {
+
+    fun transferToSet(baseValue: Int): Map<Currency, Int> {
+        var modBaseValue = baseValue
+        val values = EnumMap<Currency, Int>(Currency::class.java)
+        for (currency in currencies) {
+            val value = currency.transferTo(modBaseValue)
+            values[currency] = value
+            modBaseValue -= currency.transferFrom(value)
+        }
+        if (modBaseValue != 0)
+            throw RuntimeException() // TODO Change to ValueNotRepresentableException
+        return values
+    }
+
+    class Builder {
+
+        private val currencies = ArrayList<Currency>()
+
+        fun add(currency: Currency): Builder {
+            currencies.add(currency)
+            return this
+        }
+
+        fun create(): CurrencySet {
+            currencies.sortBy { it.multiplier }
+            return CurrencySet(currencies.toTypedArray())
+        }
+
+    }
+
+}