✨ Allow for class annotations as a default for when an annotation is not present on a method

CHANGELOG.md

@@ -24,6 +24,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
  - Allow for combined presence flags, such that `-a -b -c` is equivalent to `-abc`
+ - Allow for class annotations as a default for when an annotation is not present on a method.
 
 ## [1.0.2] - 2020-10-18
 

cloud-annotations/src/main/java/cloud/commandframework/annotations/AnnotationParser.java

@@ -106,6 +106,25 @@ public final class AnnotationParser<C> {
         ));
     }
 
+    protected static <A extends Annotation> @Nullable A getMethodOrClassAnnotation(
+            final @NonNull Method method,
+            final @NonNull Class<A> clazz
+    ) {
+        if (method.isAnnotationPresent(clazz)) {
+            return method.getAnnotation(clazz);
+        } else if (method.getDeclaringClass().isAnnotationPresent(clazz)) {
+            return method.getDeclaringClass().getAnnotation(clazz);
+        }
+        return null;
+    }
+
+    protected static <A extends Annotation> boolean methodOrClassHasAnnotation(
+            final @NonNull Method method,
+            final @NonNull Class<A> clazz
+    ) {
+        return getMethodOrClassAnnotation(method, clazz) != null;
+    }
+
     /**
      * Register an annotation mapper
      *
@@ -186,8 +205,8 @@ public final class AnnotationParser<C> {
             final String commandToken = commandMethod.value().split(" ")[0].split("\\|")[0];
             @SuppressWarnings("ALL") final CommandManager manager = this.manager;
             final SimpleCommandMeta.Builder metaBuilder = SimpleCommandMeta.builder()
-                    .with(this.metaFactory.apply(method.getAnnotations()));
+                    .with(this.metaFactory.apply(method));
-            if (method.isAnnotationPresent(Confirmation.class)) {
+            if (methodOrClassHasAnnotation(method, Confirmation.class)) {
                 metaBuilder.with(CommandConfirmationManager.CONFIRMATION_REQUIRED_META, "true");
             }
 
@@ -245,8 +264,9 @@ public final class AnnotationParser<C> {
                 }
             }
 
-            if (method.isAnnotationPresent(CommandPermission.class)) {
+            final CommandPermission commandPermission = getMethodOrClassAnnotation(method, CommandPermission.class);
-                builder = builder.permission(method.getAnnotation(CommandPermission.class).value());
+            if (commandPermission != null) {
+                builder = builder.permission(commandPermission.value());
             }
 
             if (commandMethod.requiredSender() != Object.class) {
@@ -263,7 +283,7 @@ public final class AnnotationParser<C> {
                 throw new RuntimeException("Failed to construct command execution handler", e);
             }
             /* Check if the command should be hidden */
-            if (method.isAnnotationPresent(Hidden.class)) {
+            if (methodOrClassHasAnnotation(method, Hidden.class)) {
                 builder = builder.hidden();
             }
             /* Apply flags */

cloud-annotations/src/main/java/cloud/commandframework/annotations/CommandDescription.java

@@ -34,7 +34,7 @@ import java.lang.annotation.Target;
  * Maps to {@link StandardParameters#DESCRIPTION}
  */
 @Retention(RetentionPolicy.RUNTIME)
-@Target(ElementType.METHOD)
+@Target({ElementType.METHOD, ElementType.TYPE})
 public @interface CommandDescription {
 
     /**

cloud-annotations/src/main/java/cloud/commandframework/annotations/CommandPermission.java

@@ -31,7 +31,7 @@ import java.lang.annotation.Target;
 /**
  * Equivalent to {@link cloud.commandframework.Command.Builder#permission(String)}
  */
-@Target(ElementType.METHOD)
+@Target({ElementType.METHOD, ElementType.TYPE})
 @Retention(RetentionPolicy.RUNTIME)
 public @interface CommandPermission {
 

cloud-annotations/src/main/java/cloud/commandframework/annotations/Confirmation.java

@@ -32,7 +32,7 @@ import java.lang.annotation.Target;
  * Require confirmation for the command
  */
 @Retention(RetentionPolicy.RUNTIME)
-@Target(ElementType.METHOD)
+@Target({ElementType.METHOD, ElementType.TYPE})
 public @interface Confirmation {
 
 }

cloud-annotations/src/main/java/cloud/commandframework/annotations/Hidden.java

@@ -33,7 +33,7 @@ import java.lang.annotation.Target;
 /**
  * Indicates that the command should be hidden. Similar to {@link Command.Builder#hidden()}
  */
-@Target(ElementType.METHOD)
+@Target({ElementType.METHOD, ElementType.TYPE})
 @Retention(RetentionPolicy.RUNTIME)
 public @interface Hidden {
 

cloud-annotations/src/main/java/cloud/commandframework/annotations/MetaFactory.java

@@ -28,9 +28,10 @@ import cloud.commandframework.meta.CommandMeta;
 import org.checkerframework.checker.nullness.qual.NonNull;
 
 import java.lang.annotation.Annotation;
+import java.lang.reflect.Method;
 import java.util.function.Function;
 
-class MetaFactory implements Function<@NonNull Annotation @NonNull [], @NonNull CommandMeta> {
+class MetaFactory implements Function<@NonNull Method, @NonNull CommandMeta> {
 
     private final AnnotationParser<?> annotationParser;
     private final Function<ParserParameters, CommandMeta> metaMapper;
@@ -44,17 +45,16 @@ class MetaFactory implements Function<@NonNull Annotation @NonNull [], @NonNull
     }
 
     @Override
-    public @NonNull CommandMeta apply(final @NonNull Annotation @NonNull [] annotations) {
+    public @NonNull CommandMeta apply(final @NonNull Method method) {
         final ParserParameters parameters = ParserParameters.empty();
-        for (final Annotation annotation : annotations) {
+        this.annotationParser.getAnnotationMappers().forEach(((annotationClass, mapper) -> {
-            @SuppressWarnings("ALL") final Function function = this.annotationParser.getAnnotationMappers()
+            final Annotation annotation = AnnotationParser.getMethodOrClassAnnotation(method, annotationClass);
-                    .get(annotation.annotationType());
+            if (annotation != null) {
-            if (function == null) {
+                @SuppressWarnings("ALL") final Function function = (Function) mapper;
-                continue;
-            }
                 //noinspection unchecked
                 parameters.merge((ParserParameters) function.apply(annotation));
             }
+        }));
         return this.metaMapper.apply(parameters);
     }