月度归档:2015年08月

最近处理的两个坑:Spring 启动问题与 log4j 配置

Spring 依赖注入问题

近半年,在生产环境老是出现应用在 JBoss 里启动不来,在下面的方法输出日志、进入循环后就走不出那个循环了:

Spring 3.0.5: org.springframework.beans.factory.support.DefaultListableBeanFactory

public void preInstantiateSingletons() throws BeansException {
     if (this.logger.isInfoEnabled()) {
          this.logger.info("Pre-instantiating singletons in " + this);
     }

     synchronized (this.beanDefinitionMap) {
          for (String beanName : this.beanDefinitionNames) {
               RootBeanDefinition bd = getMergedLocalBeanDefinition(beanName);
               if (!bd.isAbstract() && bd.isSingleton() && !bd.isLazyInit()) {
                    if (isFactoryBean(beanName)) {
                         final FactoryBean factory = (FactoryBean) getBean(FACTORY_BEAN_PREFIX + beanName);
                         boolean isEagerInit;
                         if (System.getSecurityManager() != null && factory instanceof SmartFactoryBean) {
                              isEagerInit = AccessController.doPrivileged(new PrivilegedAction<Boolean>() {
                                   public Boolean run() {
                                        return ((SmartFactoryBean) factory).isEagerInit();
                                   }
                              }, getAccessControlContext());
                         }
                         else {
                              isEagerInit = factory instanceof SmartFactoryBean && ((SmartFactoryBean) factory).isEagerInit(); 
                         }
                         if (isEagerInit) {
                              getBean(beanName);
                         }
                    }
                    else {
                         getBean(beanName);
                    }
               }
          }
     }
}

因为是生产环境,没法直接远程 debug,只能 dump 出栈和堆来分析,从栈来看,Spring 一直在做 bean 实例化;从堆来看,是这样的:

Top elements include:

•13,701 × Error creating bean with name ‘sqlSessionFactory’ … > (496 bytes)
•13,732 × Could not autowire method: public final void org.m… (336 bytes)
…….//还有很多其他的类创建失败

这个问题有一定的随机性,因为不是总是起不来,重启多次之后就可能顺利启动了,搞得每次发版本都胆战心惊。

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