com.vectorprint.configuration.parameters.annotation.ParamAnnotationProcessorImpl Maven / Gradle / Ivy

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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.

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/*
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package com.vectorprint.configuration.parameters.annotation;

/*
 * #%L
 * VectorPrintConfig
 * %%
 * Copyright (C) 2011 - 2013 VectorPrint
 * %%
 * 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.
 * #L%
 */
import com.vectorprint.configuration.binding.parameters.ParamBindingService;
import com.vectorprint.configuration.parameters.ParameterImpl;
import com.vectorprint.configuration.parameters.Parameterizable;
import java.io.Serializable;
import java.lang.annotation.Annotation;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.util.Arrays;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author Eduard Drenth at VectorPrint.nl
 */
public class ParamAnnotationProcessorImpl implements ParamAnnotationProcessor {

   private static final Logger log = Logger.getLogger(ParamAnnotationProcessorImpl.class.getName());

   /**
    * Looks for parameter annotations on each class in the hierarchy and
    * {@link Parameterizable#addParameter(com.vectorprint.configuration.parameters.Parameter, java.lang.Class) adds a parameter to the parameterizable}
    * for each annotation found. Skips parameters already present on the parameterizable. This implementation assumes a
    * two argument constructor like {@link ParameterImpl#ParameterImpl(java.lang.String, java.lang.String)}.
    *
    * @param parameterizable
    * @throws NoSuchMethodException
    * @throws InstantiationException
    * @throws IllegalAccessException
    * @throws InvocationTargetException
    */
   @Override
   public boolean initParameters(Parameterizable parameterizable) throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException {
      if (parameterizable.getSettings()==null||parameterizable.getSettings().isEmpty()) {
         log.warning(String.format("Initializing parameters of %s without settings, you may want to initialize settings of %s before initializing parameters",
             parameterizable.getClass().getName(),parameterizable.getClass().getName()));
      }
      Class c = parameterizable.getClass();
      while (Parameterizable.class.isAssignableFrom(c)) {
         if (log.isLoggable(Level.FINE)) {
            log.fine(String.format("looking for parameter annotations on %s", c.getName()));
         }
         process(c, parameterizable);
         c = c.getSuperclass();
      }
      return true;
   }

   private void process(Class c, Parameterizable parameterizable) throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException {
      Annotation annotation = c.getAnnotation(Parameters.class);
      if (annotation != null) {
         Parameters ps = (Parameters) annotation;
         for (Param p : ps.parameters()) {
            String key = p.key();
            if (parameterizable.getParameters().containsKey(key)) {
               if (log.isLoggable(Level.FINE)) {
                  log.fine(String.format("skipping parameter %s, already present on %s: %s", key, parameterizable.getClass().getName(), parameterizable.getParameters().get(key)));
               }
               continue;
            }
            String help = p.help();
            String def = (Param.NULL.equals(p.defaultValue())) ? null : p.defaultValue();
            String[] defArray = (Param.NULL.equals(p.defaultArray()[0])) ? null : p.defaultArray();
            Class pic = p.clazz();
            if (log.isLoggable(Level.FINE)) {
               log.fine(String.format("applying parameter %s with key %s and default %s on %s", pic.getName(), key, (def) == null ? Arrays.toString(defArray) : def, c.getName()));
            }
            Constructor con = pic.getConstructor(String.class, String.class);
            ParameterImpl pi = (ParameterImpl) con.newInstance(key, help);
            if (def != null) {
               pi.setDefault((Serializable) ParamBindingService.getInstance().getFactory().getBindingHelper().convert(def, pi.getValueClass()));
            } else if (defArray != null) {
               pi.setDefault((Serializable) ParamBindingService.getInstance().getFactory().getBindingHelper().convert(defArray, pi.getValueClass()));
            }
            parameterizable.addParameter(pi, c);
         }
      }
   }

}