src/main/java/org/springframework/context/event/DefaultPojoEventListenerManager.java

   1 /**
   2 * Copyright (C) 2017 EDIT
   3 * European Distributed Institute of Taxonomy
   4 * http://www.e-taxonomy.eu
   5 *
   6 * The contents of this file are subject to the Mozilla Public License Version 1.1
   7 * See LICENSE.TXT at the top of this package for the full license terms.
   8 */
   9 package org.springframework.context.event;
  10
  11 import java.io.Serializable;
  12 import java.lang.reflect.Method;
  13 import java.util.ArrayList;
  14 import java.util.Collection;
  15 import java.util.HashMap;
  16 import java.util.Map;
  17
  18 import org.apache.logging.log4j.LogManager;
  19 import org.apache.logging.log4j.Logger;
  20 import org.springframework.beans.BeansException;
  21 import org.springframework.beans.factory.annotation.Autowired;
  22 import org.springframework.context.ApplicationContext;
  23 import org.springframework.context.ApplicationContextAware;
  24 import org.springframework.context.ApplicationListener;
  25 import org.springframework.core.annotation.AnnotationUtils;
  26 import org.springframework.util.ReflectionUtils;
  27
  28 import com.vaadin.spring.annotation.SpringComponent;
  29 import com.vaadin.spring.annotation.UIScope;
  30
  31 /**
  32  * The DefaultPojoEventListenerManager helps sending events to  event listener methods defined in beans
  33  * which are not manages by the Spring {@link ApplicationEventMulticaster}. The {@link ApplicationEventMulticaster}
  34  * for example misses sending events to spring beans with scope "Prototype".
  35  *
  36  * @author a.kohlbecker
  37  * @since May 29, 2017
  38  */
  39 @SpringComponent
  40 @UIScope
  41 public class DefaultPojoEventListenerManager implements PojoEventListenerManager, ApplicationContextAware, Serializable {
  42
  43     private static final long serialVersionUID = -6814417168274166953L;
  44
  45     private static final Logger logger = LogManager.getLogger();
  46
  47     @Autowired
  48     private ApplicationEventMulticaster applicationEventMulticaster;
  49
  50     private final EventExpressionEvaluator evaluator = new EventExpressionEvaluator();
  51
  52     private Map<Object, Collection<ApplicationListener<?>>> listenerMap = new HashMap<>();
  53
  54     private ApplicationContext applicationContext;
  55
  56     @Override
  57     public void addEventListeners(Object o){
  58
  59         Method[] methods = ReflectionUtils.getUniqueDeclaredMethods(o.getClass());
  60         for (Method method : methods) {
  61             EventListener eventListener = AnnotationUtils.findAnnotation(method, EventListener.class);
  62             if (eventListener == null) {
  63                 continue;
  64             }
  65             ApplicationListenerPojoMethodAdapter applicationListener = new ApplicationListenerPojoMethodAdapter(o.toString(), o.getClass(), method, o);
  66             applicationListener.init(this.applicationContext, this.evaluator);
  67
  68             if(logger.isTraceEnabled()){
  69                 logger.trace(String.format("Adding ApplicationListener for  %s@%s#%s", o.getClass().getSimpleName(), o.hashCode(), method.toGenericString()));
  70             }
  71             applicationEventMulticaster.addApplicationListener(applicationListener);
  72             addToMap(o, applicationListener);
  73
  74         }
  75     }
  76
  77     @Override
  78     public void removeEventListeners(Object o){
  79         if(listenerMap.containsKey(o)){
  80             listenerMap.get(o).forEach(l -> applicationEventMulticaster.removeApplicationListener(l));
  81             listenerMap.remove(o);
  82         }
  83     }
  84
  85     private void addToMap(Object o, ApplicationListener<?> applicationListener) {
  86         if(!listenerMap.containsKey(o)){
  87             listenerMap.put(o, new ArrayList<>());
  88         }
  89         listenerMap.get(o).add(applicationListener);
  90     }
  91
  92     /**
  93      * {@inheritDoc}
  94      */
  95     @Override
  96     public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
  97         this.applicationContext = applicationContext;
  98     }
  99
 100 }