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    <p>I have managed to hack something together based on <a href="http://developers-blog.org/blog/default/2009/07/13/Spring-AOP-Example" rel="nofollow">this Spring AOP Example</a>.</p> <p>I am not yet up to speed with Spring 3 so I have implemented this using Spring 2.5 - I dare say there are more elegant ways of achieving what you want. I have implemented this using <strong>System.out</strong>'s for simplicity but these could easily be converted to log4j calls.</p> <p>Initially I create a map between the Spring's bean names and the string representation of the object (<strong>InitBean</strong>). This map is used inside the <em>MethodInterceptor</em> - I did try making the <em>MethodInterceptor</em> an <em>InitializingBean</em> but the <em>MethodInterceptor</em> stopped working for some reason.</p> <p>Performing an equals between the bean passed in via the <em>MethodInterceptor</em> and the other beans in the application context did not work. e.g. by using something like "<strong><em>ctx.getBeansOfType(GoBean.class)</em></strong>" inside the <em>MethodInterceptor</em>. I presume this is because the object passed in via the <em>MethodInvocation</em> was a <em>GoBean</em> whereas objects obtained from the application context at this point are proxied (e.g. something like <strong><em>example.GoBean$$EnhancerByCGLIB$$bd27d40e</em></strong>).</p> <p>This is why I had to resort to a comparison of object string representations (which is not ideal). Also I specifically do not want to activate the <em>MethodInterceptor</em> logic when calling the "<strong><em>toString</em></strong>" method on an object (as since I'm using toString elsewhere leads to infinite loops and StackOverflow).</p> <p>I hope this is useful,</p> <p><strong>applicationContext.xml</strong></p> <pre><code>&lt;beans&gt; &lt;bean name="initBean" class="example.InitBean"/&gt; &lt;bean name="methodLoggingInterceptor" class="example.MethodLoggingInterceptor"&gt; &lt;property name="initBean" ref="initBean"/&gt; &lt;/bean&gt; &lt;bean name="proxyCreator" class="org.springframework.aop.framework.autoproxy.BeanNameAutoProxyCreator"&gt; &lt;property name="beanNames"&gt; &lt;list&gt; &lt;value&gt;go*&lt;/value&gt; &lt;/list&gt; &lt;/property&gt; &lt;property name="interceptorNames"&gt; &lt;list&gt; &lt;value&gt;methodLoggingInterceptor&lt;/value&gt; &lt;/list&gt; &lt;/property&gt; &lt;/bean&gt; &lt;bean name="goBean1" class="example.GoBean" /&gt; &lt;bean name="goBean2" class="example.GoBean" /&gt; &lt;bean name="goBean3" class="example.GoBean" /&gt; &lt;/beans&gt; </code></pre> <p><strong>GoBean.java</strong></p> <pre><code>public class GoBean { public void execute(){ System.out.println(new Date()); } } </code></pre> <p><strong>SimpleTestClass.java</strong></p> <pre><code>public static void main( String[] args ){ ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml"); ArrayList&lt;GoBean&gt; goBeans = new ArrayList&lt;GoBean&gt;(); goBeans.add((GoBean) ctx.getBean("goBean1")); goBeans.add((GoBean) ctx.getBean("goBean2")); goBeans.add((GoBean) ctx.getBean("goBean3")); for(GoBean g: goBeans){ g.execute(); } } </code></pre> <p><strong>InitBean.java</strong></p> <pre><code>public class InitBean implements ApplicationContextAware, InitializingBean { private ApplicationContext ctx; private Map&lt;String, String&gt; beanMap = new HashMap&lt;String,String&gt;(); public void setApplicationContext(ApplicationContext ac) throws BeansException { ctx = ac; } public void afterPropertiesSet() throws Exception { for(String beanName: ctx.getBeanNamesForType(GoBean.class)){ beanMap.put(ctx.getBean(beanName).toString(), beanName); } } public Map&lt;String,String&gt; getBeanMap(){ return beanMap; } } </code></pre> <p><strong>MethodLoggingInterceptor.java</strong></p> <pre><code>public class MethodLoggingInterceptor implements MethodInterceptor{ private InitBean initBean; public Object invoke(MethodInvocation method) throws Throwable { if (!"toString".equals(method.getMethod().getName())) { StringBuilder sb = new StringBuilder(); Object obj = method.getThis(); if (obj instanceof GoBean) { Map&lt;String,String&gt; beanMap = initBean.getBeanMap(); String objToString = obj.toString(); if (beanMap.containsKey(objToString)) { System.out.println(beanMap.get(objToString)); sb.append("bean: "); sb.append(beanMap.get(objToString)); sb.append(" : "); } } sb.append(method.getMethod().getDeclaringClass()); sb.append('.'); sb.append(method.getMethod().getName()); System.out.println(sb.toString() + " starts"); Object result = method.proceed(); System.out.println(sb.toString() + " finished"); return result; } else { return method.proceed(); } } public void setInitBean(InitBean ib) { this.initBean = ib; } } </code></pre>
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    1. POLogging bean id into log4j logfile without BeanNameAware interface
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    1. USMark McLaren
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    1. COThanks for your effort to provide a nice example. One question is missing, which is how to prevent leaks in case of prototype beans?
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      1. USGábor Lipták
    2. COI don't think my solution would work for prototype beans. The beans wouldn't be recorded correctly in the InitializingBean (InitBean) and so the MethodInterceptor wouldn't be able to identify them. To capture prototype bean names you could try and implement something via the BeanFactory perhaps using some variant of BeanPostProcessor. I suspect you would need some sort of BeanPostProcessor to control the prototype bean's lifecycle too (and hence prevent leaks).
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      1. USMark McLaren
    3. COThe InitBean can implement the BeanPostProcessor interface in which case it will be handed a reference to each Bean object once it is fully initialized. This will be invoked for prototype beans as well. By using a WeakHashMap you can also deal with the memory issue - once the bean is not referred from anywhere else the next GC cycle would remove the corresponding entry from the map.
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