我在我的应用程序中使用 tomcat 7。当我启动服务器时，它会在启动时向我显示以下警告消息：-
May 15, 2013 11:45:10 AM org.apache.tomcat.jdbc.pool.ConnectionPool abandon
WARNING: Connection has been abandoned PooledConnection[oracle.jdbc.driver.T4CConnection@d6d9b4]:java.lang.Exception
at org.apache.tomcat.jdbc.pool.ConnectionPool.getThreadDump(ConnectionPool.java:1006)
at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:672)
at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:607)
at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:470)
at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:135)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:112)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:99)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:123)
at org.hibernate.ejb.connection.InjectedDataSourceConnectionProvider.getConnection(InjectedDataSourceConnectionProvider.java:67)
at org.hibernate.engine.jdbc.internal.JdbcServicesImpl$ConnectionProviderJdbcConnectionAccess.obtainConnection(JdbcServicesImpl.java:253)
at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:119)
at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:75)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:159)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:131)
at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:71)
at org.hibernate.cfg.Configuration.buildSettingsInternal(Configuration.java:2270)
at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2266)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1735)
at org.hibernate.ejb.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:84)
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:904)
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:889)
at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:73)
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:268)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:310)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1514)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1452)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:400)
at org.springframework.beans.factory.BeanFactoryUtils.beansOfTypeIncludingAncestors(BeanFactoryUtils.java:275)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.detectPersistenceExceptionTranslators(PersistenceExceptionTranslationInterceptor.java:139)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.<init>(PersistenceExceptionTranslationInterceptor.java:79)
at org.springframework.dao.annotation.PersistenceExceptionTranslationAdvisor.<init>(PersistenceExceptionTranslationAdvisor.java:70)
at org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor.setBeanFactory(PersistenceExceptionTranslationPostProcessor.java:103)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeAwareMethods(AbstractAutowireCapableBeanFactory.java:1475)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1443)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
at org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:728)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:449)
at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:385)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:284)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:111)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4723)
at org.apache.catalina.core.StandardContext$1.call(StandardContext.java:5226)
at org.apache.catalina.core.StandardContext$1.call(StandardContext.java:5221)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)
不知道出了什么问题。请帮助我摆脱这个警告，因为它会导致其他问题。