Move isOptional call

Author: dualspiral

src/main/java/org/spongepowered/api/command/parameter/Parameter.java

@@ -64,6 +64,7 @@
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.UUID;
 import java.util.function.Function;
 import java.util.function.Predicate;
@@ -769,6 +770,13 @@ static <T> Parameter.Value.Builder<T> literal(Class<T> returnType, T returnedVal
      */
     Text getUsage(CommandCause cause);
 
+    /**
+     * Gets whether this parameter is optional.
+     *
+     * @return true if optional, else false.
+     */
+    boolean isOptional();
+
     /**
      * A {@link Key}
      *
@@ -860,13 +868,6 @@ interface Value<T> extends Parameter {
          */
         Predicate<CommandCause> getRequirement();
 
-        /**
-         * Gets whether this parameter is optional.
-         *
-         * @return true if optional, else false.
-         */
-        boolean isOptional();
-
         /**
          * Builds a {@link Parameter} from constituent components.
          */
@@ -1104,6 +1105,13 @@ interface Subcommand extends Parameter {
          */
         Command getCommand();
 
+        /**
+         * The alias for the subcommand.
+         *
+         * @return The subcommand.
+         */
+        Set<String> getAliases();
+
         interface Builder extends ResettableBuilder<Subcommand, Builder> {
 
             /**