Merge pull request 'Add SWCommand.StaticValue' (#137) from CMDStaticValue into master

Reviewed-on: #137
Reviewed-by: Lixfel <lixfel@steamwar.de>

SpigotCore_Main/src/de/steamwar/command/SWCommand.java

@@ -328,4 +328,10 @@ public abstract class SWCommand {
 
         boolean local() default false;
     }
+
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target({ElementType.PARAMETER})
+    protected @interface StaticValue {
+        String value();
+    }
 }

SpigotCore_Main/src/de/steamwar/command/SWCommandUtils.java

@@ -163,6 +163,10 @@ public class SWCommandUtils {
         GUARD_FUNCTIONS.putIfAbsent(name, guardChecker);
     }
 
+    public static TypeMapper<String> createMapper(String value) {
+        return createMapper((s) -> value.equals(s) ? value : null, s -> Collections.singletonList(value));
+    }
+
     public static <T> TypeMapper<T> createMapper(Function<String, T> mapper, Function<String, List<String>> tabCompleter) {
         return createMapper(mapper, (commandSender, s) -> tabCompleter.apply(s));
     }

SpigotCore_Main/src/de/steamwar/command/SubCommand.java

@@ -84,6 +84,13 @@ class SubCommand {
             String name = clazz.getTypeName();
             if (mapper != null) {
                 name = mapper.value();
+            } else {
+                SWCommand.StaticValue staticValue = parameter.getAnnotation(SWCommand.StaticValue.class);
+                if (parameter.getType() == String.class) {
+                    arguments[i - 1] = SWCommandUtils.createMapper(staticValue.value());
+                    guards[i - 1] = getGuardChecker(parameter, localGuardChecker);
+                    continue;
+                }
             }
             arguments[i - 1] = localTypeMapper.containsKey(name)
                     ? localTypeMapper.get(name)