com.vectorprint.configuration.cdi.RequiredInterceptor Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of Config Show documentation

This project is about configuration of applications and about parameterization of Objects. This library offers annotations (and annotation processors), parsers, typing, observing changes, serialization, cloning and more when working with settings and/or object parameters. Settings and its features can be declared using an xml format. The library offers syntax support for settings and parameters in a loosely coupled manner. You are not restricted to built in syntax, you can provide your own. At runtime this library tracks keys for which a default is used because they are not found in settings. Also it tracks unused keys. You can stack features for settings such as caching, preparing keys and values, readonlyness, threadsafety, helpsupport, reading / parsing from input. You can easily develop your own features for settings.

There is a newer version: 12.2

Show newest version

/*
 * Copyright 2018 Fryske Akademy.
 *
 * 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 com.vectorprint.configuration.cdi;

import com.vectorprint.configuration.NoValueException;

import javax.annotation.Priority;
import javax.enterprise.inject.spi.InjectionPoint;
import javax.interceptor.AroundInvoke;
import javax.interceptor.Interceptor;
import javax.interceptor.InvocationContext;

/**
 *
 * @author eduard
 */
@CheckRequired @Interceptor
@Priority(Interceptor.Priority.APPLICATION)
class RequiredInterceptor {

   @AroundInvoke
   public Object checkRequired(InvocationContext ctx) throws Exception {
       if (ctx.getMethod().isAnnotationPresent(Property.class)) {
           InjectionPoint ip = (InjectionPoint) ctx.getParameters()[0];
           boolean required = ip.getAnnotated().getAnnotation(Property.class).required()
                   && ip.getAnnotated().getAnnotation(Property.class).defaultValue().length==0;
           try {
               return ctx.proceed();
           } catch (NoValueException ex) { // thrown by Settings#handleNoValue
               if (required) throw ex;
               else return null;
           }
       } else {
           return ctx.proceed();
       }
   }    
}