使用Junit4进行单元测试没法实现@BeforeClass注解及出现application.xml没法加载问题

@BeforeClass没法加载主要是写的单元测试类继承了TestCase类，继承了该类则导致所有的注解全部无效。
 
 
出现的错误只能在main函数才会提示，而junit没提示错误出来。
org.apache.xerces.jaxp.DocumentBuilderFactoryImpl not found

缺少xercesImpl.jar这个包

下载地址：
http://archive.apache.org/dist/xml/xerces-j/
Exception in thread "main" org.springframework.beans.factory.BeanDefinitionStoreException: Unexpected exception parsing XML document from class path resource [applicationContext.xml]; nested exception is javax.xml.parsers.FactoryConfigurationError: Provider
org.apache.xerces.jaxp.DocumentBuilderFactoryImpl not found

at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:420)

at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:342)

at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:310)

at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:143)

at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:178)

at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:149)

at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:212)

at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:113)

at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:80)

at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:123)

at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:423)

at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:353)

at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)

at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:93)