Added more kotlin utilities

eco-api/src/main/java/com/willfp/eco/util/NamespacedKeyUtils.java

@@ -3,6 +3,9 @@ package com.willfp.eco.util;
 import com.willfp.eco.core.Eco;
 import org.bukkit.NamespacedKey;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Objects;
 
 /**
  * Utilities / API methods for {@link NamespacedKey}s.
@@ -45,8 +48,25 @@ public final class NamespacedKeyUtils {
      */
     @NotNull
     public static NamespacedKey fromString(@NotNull final String string) {
+        return Objects.requireNonNull(NamespacedKeyUtils.fromStringOrNull(string));
+    }
+
+    /**
+     * Create a NamespacedKey from a string.
+     * <p>
+     * Preferred over {@link NamespacedKey#fromString(String)} for performance reasons.
+     *
+     * @param string The string.
+     * @return The key, or null if not a key.
+     */
+    @Nullable
+    public static NamespacedKey fromStringOrNull(@NotNull final String string) {
         int index = string.indexOf(":");
 
+        if (index < 0) {
+            return null;
+        }
+
         return NamespacedKeyUtils.create(
                 string.substring(0, index),
                 string.substring(index + 1)

eco-api/src/main/kotlin/com/willfp/eco/util/ListUtils.kt

@@ -13,3 +13,9 @@ fun <T> List<T>.toFrequencyMap(): Map<T, Int> =
  */
 fun Iterable<String>.containsIgnoreCase(element: String): Boolean =
     ListUtils.containsIgnoreCase(this, element)
+
+/**
+ * @see ListUtils.create2DList
+ */
+fun <T> create2DList(rows: Int, columns: Int): List<List<T>> =
+    ListUtils.create2DList(rows, columns)

eco-api/src/main/kotlin/com/willfp/eco/util/NamespacedKeyUtils.kt

@@ -0,0 +1,21 @@
+@file:JvmName("NamespacedKeyUtilsExtensions")
+
+package com.willfp.eco.util
+
+/**
+ * @see NamespacedKeyUtils.fromString
+ */
+fun namespacedKeyOf(string: String) =
+    NamespacedKeyUtils.fromString(string)
+
+/**
+ * @see NamespacedKeyUtils.fromString
+ */
+fun safeNamespacedKeyOf(string: String) =
+    NamespacedKeyUtils.fromStringOrNull(string)
+
+/**
+ * @see NamespacedKeyUtils.create
+ */
+fun namespacedKeyOf(namespace: String, key: String) =
+    NamespacedKeyUtils.create(namespace, key)