t3.plugin.annotations.helpers.CategoriesHelper Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of t3-common Show documentation
Utility classes for T³ projects
The newest version!
/**
 * (C) Copyright 2016-2019 teecube
 * (https://teecu.be) and others.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package t3.plugin.annotations.helpers;

import t3.plugin.annotations.Categories;
import t3.plugin.annotations.Category;
import t3.plugin.annotations.impl.CategoryImpl;

import java.lang.annotation.Annotation;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.HashSet;
import java.util.Set;

/**
 *
 * @author Mathieu Debove <[email protected]>
 *
 */
public class CategoriesHelper {

    private static String getTitle(Annotation annotation) {
        return (String) getObject(annotation, "title");
    }

    private static String getDescription(Annotation annotation) {
        return (String) getObject(annotation, "description");
    }

    private static Object[] getCategories(Annotation annotation) {
        return (Object[]) getObject(annotation, "value");
    }
    
    private static Object getObject(Annotation annotation, String methodName) {
        InvocationHandler handler = Proxy.getInvocationHandler(annotation);
        Method method;
        try {
            method = annotation.annotationType().getMethod(methodName, (Class[]) null);
            return handler.invoke(annotation, method, null);
        } catch (Throwable e) {
            return null;
        }
    }

    public static  Set getCategories(Set> types) {
        Set result = new HashSet();

        String title = null;
        String description = null;

        for (Class type : types) {
            Categories categories = type.getAnnotation(Categories.class);
            if (categories == null) {
                for (Annotation a1 : type.getAnnotations()) {
                    if (a1.annotationType().getCanonicalName().equals(Categories.class.getCanonicalName())) {
                        Object[] categories_ = getCategories(a1);
                        for (Object category : categories_) {
                            Annotation a2 = (Annotation) category;
                            title = getTitle(a2);
                            description = getDescription(a2);
                            result.add(new CategoryImpl(title, description));
                        }
                    }
                }
            } else {
                for (Category category : categories.value()) {
                    title = getTitle(category);
                    description = getDescription(category);
                    result.add(new CategoryImpl(title, description));
                }
            }
        }

        return result;
    }

}