本异常是小编在运行自己另外一篇博文中的例子时遇到的。（附博文：http://www.cnblogs.com/dudududu/p/8482487.html）
完整异常信息：
警告: Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'a' defined in class path resource [aop_hello.xml]: BeanPostProcessor before instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.aop.aspectj.AspectJPointcutAdvisor#0': Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.aop.aspectj.AspectJPointcutAdvisor]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Pointcut is not well-formed: expecting 'name pattern' at character position 33
execution(*com.edu.aop.hello.A.*())
^ Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'a' defined in class path resource [aop_hello.xml]: BeanPostProcessor before instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.aop.aspectj.AspectJPointcutAdvisor#0': Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.aop.aspectj.AspectJPointcutAdvisor]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Pointcut is not well-formed: expecting 'name pattern' at character position 33
execution(*com.edu.aop.hello.A.*())
^ at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:497)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:312)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:310)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:200)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:760)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:868)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:144)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:85)
at com.edu.aop.hello.Main.main(Main.java:11)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.aop.aspectj.AspectJPointcutAdvisor#0': Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.aop.aspectj.AspectJPointcutAdvisor]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Pointcut is not well-formed: expecting 'name pattern' at character position 33
execution(*com.edu.aop.hello.A.*())
^ at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:278)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1270)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1127)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:502)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:312)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:310)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:205)
at org.springframework.aop.framework.autoproxy.BeanFactoryAdvisorRetrievalHelper.findAdvisorBeans(BeanFactoryAdvisorRetrievalHelper.java:94)
at org.springframework.aop.framework.autoproxy.AbstractAdvisorAutoProxyCreator.findCandidateAdvisors(AbstractAdvisorAutoProxyCreator.java:107)
at org.springframework.aop.aspectj.autoproxy.AspectJAwareAdvisorAutoProxyCreator.shouldSkip(AspectJAwareAdvisorAutoProxyCreator.java:103)
at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.postProcessBeforeInstantiation(AbstractAutoProxyCreator.java:254)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsBeforeInstantiation(AbstractAutowireCapableBeanFactory.java:1063)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.resolveBeforeInstantiation(AbstractAutowireCapableBeanFactory.java:1036)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:491)
... 10 more
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.aop.aspectj.AspectJPointcutAdvisor]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Pointcut is not well-formed: expecting 'name pattern' at character position 33
execution(*com.edu.aop.hello.A.*())
^ at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:182)
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:117)
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:271)
... 25 more
Caused by: java.lang.IllegalArgumentException: Pointcut is not well-formed: expecting 'name pattern' at character position 33
execution(*com.edu.aop.hello.A.*())
^ at org.aspectj.weaver.tools.PointcutParser.resolvePointcutExpression(PointcutParser.java:334)
at org.aspectj.weaver.tools.PointcutParser.parsePointcutExpression(PointcutParser.java:312)
at org.springframework.aop.aspectj.AspectJExpressionPointcut.buildPointcutExpression(AspectJExpressionPointcut.java:226)
at org.springframework.aop.aspectj.AspectJExpressionPointcut.obtainPointcutExpression(AspectJExpressionPointcut.java:197)
at org.springframework.aop.aspectj.AspectJExpressionPointcut.getMethodMatcher(AspectJExpressionPointcut.java:182)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.buildSafePointcut(AbstractAspectJAdvice.java:202)
at org.springframework.aop.aspectj.AspectJPointcutAdvisor.<init>(AspectJPointcutAdvisor.java:52)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:170)
... 27 more
看到这个异常，才疏学浅的小编也是一头雾水，查了几篇相关博主的博文和官网相关信息，结合自身运行环境和例子运行，并未找到解决的方法。
几经折腾，小编发现自己犯了个极其愚蠢的错误：
在AOP的配置文件中的一句：
<aop:before method="methodX1" pointcut="execution(*com.edu.aop.hello.A.*())"></aop:before>
其中使用到了通配符，第一个通配符"*"表示 public void ,因此需和后面表达式代码留出空格。小编遇到的错误恰恰是未留空格造成的。
于是改成：
<aop:before method="methodX1" pointcut="execution(* com.edu.aop.hello.A.*())"></aop:before>
就可以完美运行了。
希望和小编遇到相同异常问题的同学能引以为戒。