自己写的项目，从一台电脑导入到另一台电脑，部署的时候报错：如下
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'freeMarkerConfigurer' defined in ServletContext resource [/WEB-INF/classes/spring/applicationContext-freemaker.xml]: Cannot resolve reference to bean 'testTag' while setting bean property 'freemarkerVariables' with key [TypedStringValue: value [testTag], target type [null]]; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Error loading class [com.qiang.tag.TestTag] for bean with name 'testTag' defined in file [G:\Software\Tomcat\jspTomcat\jspTomcat\webapps\freemaker\WEB-INF\classes\com\qiang\tag\TestTag.class]: problem with class file or dependent class; nested exception is java.lang.UnsupportedClassVersionError: com/qiang/tag/TestTag : Unsupported major.minor version 52.0 (unable to load class com.qiang.tag.TestTag)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:359)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:108)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveManagedMap(BeanDefinitionValueResolver.java:407)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:165)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1469)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:762)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
at org.springframework.context.support.AbstractApplicationContext.__refresh(AbstractApplicationContext.java:480)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:41010)
at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4973)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5467)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.springframework.beans.factory.CannotLoadBeanClassException: Error loading class [com.qiang.tag.TestTag] for bean with name 'testTag' defined in file [G:\Software\Tomcat\jspTomcat\jspTomcat\webapps\freemaker\WEB-INF\classes\com\qiang\tag\TestTag.class]: problem with class file or dependent class; nested exception is java.lang.UnsupportedClassVersionError: com/qiang/tag/TestTag : Unsupported major.minor version 52.0 (unable to load class com.qiang.tag.TestTag)
at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1331)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:453)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:351)
... 27 more
Caused by: java.lang.UnsupportedClassVersionError: com/qiang/tag/TestTag : Unsupported major.minor version 52.0 (unable to load class com.qiang.tag.TestTag)
at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2961)
at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1210)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1690)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1571)
at org.springframework.util.ClassUtils.forName(ClassUtils.java:249)
at org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:395)
at org.springframework.beans.factory.support.AbstractBeanFactory.doResolveBeanClass(AbstractBeanFactory.java:1349)
at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1320)
... 33 more
从网上看到的说jdk版本不一致导致的，于是在Eclipse中将项目的编码
如下步骤：1、在项目右键，然后按照图示操作（注意：下面的jdk1.8是小编的jdk版本，具体的按照你本机的来）
2、在Eclipse上面选择 window----》preference，具体操作如下
3、完成这些步骤之后还是同样出现告诉我Caused by: java.lang.UnsupportedClassVersionError ，这个时候就需要看看你tomcat的运行的JRE环境了。
4、继续操作
5、恭喜您，完事
注意：（三次出现jdk的地方版本要一致）