Add help command System to SWCommand

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

@@ -22,20 +22,15 @@ package de.steamwar.command;
 import org.bukkit.command.Command;
 import org.bukkit.command.CommandSender;
 
-import java.lang.annotation.ElementType;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
+import java.lang.annotation.*;
 import java.lang.reflect.Method;
 import java.lang.reflect.Parameter;
 import java.util.*;
-import java.util.function.Consumer;
 
 public abstract class SWCommand {
 
     private final Set<SubCommand> commandSet = new HashSet<>();
-    private Consumer<CommandSender> helpMessage = sender -> {
-    };
+    private final Set<SubCommand> commandHelpSet = new HashSet<>();
 
     protected SWCommand(String command) {
         this(command, new String[0]);
@@ -50,7 +45,11 @@ public abstract class SWCommand {
                         return false;
                     }
                 }
-                helpMessage.accept(sender);
+                for (SubCommand subCommand : commandHelpSet) {
+                    if (subCommand.invoke(sender, args)) {
+                        return false;
+                    }
+                }
                 return false;
             }
 
@@ -77,14 +76,14 @@ public abstract class SWCommand {
         for (Method method : getClass().getDeclaredMethods()) {
             addMapper(method);
             addCommand(method, commandMethods);
+            addHelp(method);
         }
         commandMethods.forEach(method -> commandSet.add(new SubCommand(this, method)));
     }
 
     private void addCommand(Method method, Set<Method> commandMethods) {
-        Register register = method.getDeclaredAnnotation(Register.class);
-        Mapper methodMapper = method.getDeclaredAnnotation(Mapper.class);
-        if (register == null || methodMapper != null) {
+        Register register = getAnnotation(method, Register.class);
+        if (register == null) {
             return;
         }
 
@@ -114,10 +113,25 @@ public abstract class SWCommand {
         commandMethods.add(method);
     }
 
+    private void addHelp(Method method) {
+        RegisterHelp registerHelp = getAnnotation(method, RegisterHelp.class);
+        if (registerHelp == null) {
+            return;
+        }
+
+        Parameter[] parameters = method.getParameters();
+        if (parameters.length != 1) {
+            return;
+        }
+        if (!CommandSender.class.isAssignableFrom(parameters[0].getType())) {
+            return;
+        }
+        commandHelpSet.add(new SubCommand(this, method));
+    }
+
     private void addMapper(Method method) {
-        Register register = method.getDeclaredAnnotation(Register.class);
-        Mapper methodMapper = method.getDeclaredAnnotation(Mapper.class);
-        if (register != null || methodMapper == null) {
+        Mapper mapper = getAnnotation(method, Mapper.class);
+        if (mapper == null) {
             return;
         }
 
@@ -131,19 +145,15 @@ public abstract class SWCommand {
         try {
             method.setAccessible(true);
             Object object = method.invoke(this);
-            SWCommandUtils.addMapper(methodMapper.value(), (TypeMapper<?>) object);
+            SWCommandUtils.addMapper(mapper.value(), (TypeMapper<?>) object);
         } catch (Exception e) {
             throw new SecurityException(e.getMessage(), e);
         }
     }
 
-    protected final void setHelpMessage(Consumer<CommandSender> helpMessage) {
-        assert helpMessage != null;
-        this.helpMessage = helpMessage;
-    }
-
-    protected final <T extends CommandSender> void sendHelpMessage(T sender) {
-        helpMessage.accept(sender);
+    private <T extends Annotation> T getAnnotation(Method method, Class<T> annotation) {
+        if (method.getAnnotations().length != 1) return null;
+        return method.getAnnotation(annotation);
     }
 
     @Retention(RetentionPolicy.RUNTIME)
@@ -152,6 +162,12 @@ public abstract class SWCommand {
         String[] value() default {};
     }
 
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target({ElementType.METHOD})
+    protected @interface RegisterHelp {
+        String[] value() default {};
+    }
+
     @Retention(RetentionPolicy.RUNTIME)
     @Target({ElementType.PARAMETER, ElementType.METHOD})
     protected @interface Mapper {