✨ Add flag support to the annotation system.

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

@@ -0,0 +1,69 @@
+//
+// MIT License
+//
+// Copyright (c) 2020 Alexander Söderberg & Contributors
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+package cloud.commandframework.annotations;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Indicates that the parameter should be treated like a {@link cloud.commandframework.arguments.flags.CommandFlag}.
+ * If the parameter is a {@code boolean} then a presence flag will be created, else a value flag will be created
+ * and the parser will be resolved the same way as it would for a {@link Argument}
+ */
+@Target(ElementType.PARAMETER)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface Flag {
+
+    /**
+     * The flag name
+     *
+     * @return Flag name
+     */
+    String value();
+
+    /**
+     * Flag aliases
+     *
+     * @return Aliases
+     */
+    String[] aliases() default "";
+
+    /**
+     * Name of the parser. Leave empty to use
+     * the default parser for the parameter type
+     *
+     * @return Parser name
+     */
+    String parserName() default "";
+
+    /**
+     * The argument description
+     *
+     * @return Argument description
+     */
+    String description() default "";
+
+}