Add AbstractSWCommand.OptionalValue.onlyUINIG

src/de/steamwar/command/AbstractSWCommand.java

@@ -386,6 +386,11 @@ public abstract class AbstractSWCommand<T> {
          * Will pe parsed against the TypeMapper specified by the parameter or annotation.
          */
         String value();
+
+        /**
+         * The method name stands for 'onlyUseIfNoneIsGiven'.
+         */
+        boolean onlyUINIG() default false;
     }
 
     @Retention(RetentionPolicy.RUNTIME)

src/de/steamwar/command/CommandPart.java

@@ -23,7 +23,6 @@ import lombok.AllArgsConstructor;
 import lombok.Setter;
 
 import java.lang.reflect.Array;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
@@ -52,6 +51,9 @@ class CommandPart<T> {
     @Setter
     private boolean ignoreAsArgument = false;
 
+    @Setter
+    private boolean onlyUseIfNoneIsGiven = false;
+
     public CommandPart(AbstractSWCommand<T> command, AbstractTypeMapper<T, ?> typeMapper, AbstractValidator<T, Object> validator, AbstractGuardChecker<T> guardChecker, Class<?> varArgType, String optional, GuardCheckType guardCheckType) {
         this.command = command;
         this.typeMapper = typeMapper;
@@ -113,7 +115,11 @@ class CommandPart<T> {
         }
         if (!validArgument.success) {
             if (!ignoreAsArgument) {
-                current.add(typeMapper.map(sender, EMPTY_ARRAY, optional));
+                if (!onlyUseIfNoneIsGiven) {
+                    current.add(typeMapper.map(sender, EMPTY_ARRAY, optional));
+                } else if(startIndex >= args.length) {
+                    current.add(typeMapper.map(sender, EMPTY_ARRAY, optional));
+                }
             }
             if (next != null) {
                 next.generateArgumentArray(errors, current, sender, args, startIndex);

src/de/steamwar/command/SWCommandUtils.java

@@ -101,6 +101,7 @@ public class SWCommandUtils {
             AbstractSWCommand.OptionalValue optionalValue = parameter.getAnnotation(AbstractSWCommand.OptionalValue.class);
 
             CommandPart<T> commandPart = new CommandPart<>(command, typeMapper, validator, guardChecker, varArgType, optionalValue != null ? optionalValue.value() : null, help ? GuardCheckType.HELP_COMMAND : GuardCheckType.COMMAND);
+            commandPart.setOnlyUseIfNoneIsGiven(optionalValue != null && optionalValue.onlyUINIG());
             if (current != null) {
                 current.setNext(commandPart);
             }