TOMCAT启动报错，用的是SpringMvc，我看着有个zxing的什么错误，但是没找到，求助

错误是

严重: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping#0': Invocation of init method failed; nested exception is java.lang.UnsupportedClassVersionError: com/google/zxing/WriterException : Unsupported major.minor version 51.0 (unable to load class com.google.zxing.WriterException)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1553)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:703)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4939)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1113)
at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1671)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:439)
at java.util.concurrent.FutureTask$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:662)
Caused by: java.lang.UnsupportedClassVersionError: com/google/zxing/WriterException : Unsupported major.minor version 51.0 (unable to load class com.google.zxing.WriterException)
at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2899)
at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1173)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1681)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
at java.lang.Class.getDeclaredMethods(Class.java:1791)
at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:474)
at org.springframework.web.method.HandlerMethodSelector.selectMethods(HandlerMethodSelector.java:57)
at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.detectHandlerMethods(AbstractHandlerMethodMapping.java:149)
at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.initHandlerMethods(AbstractHandlerMethodMapping.java:124)
at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.afterPropertiesSet(AbstractHandlerMethodMapping.java:103)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping.afterPropertiesSet(RequestMappingHandlerMapping.java:126)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1612)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1549)
... 26 more
2017-7-20 14:31:03 org.apache.catalina.core.StandardContext startInternal
严重: Error listenerStart
2017-7-20 14:31:03 org.apache.catalina.core.StandardContext startInternal
严重: Context [/yzpt] startup failed due to previous errors
2017-7-20 14:31:03 org.apache.catalina.core.ApplicationContext log
信息: Closing Spring root WebApplicationContext
2017-7-20 14:31:03 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [/yzpt] appears to have started a thread named [Timer-2] but has failed to stop it. This is very likely to create a memory leak.
2017-7-20 14:31:03 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [/yzpt] appears to have started a thread named [Abandoned connection cleanup thread] but has failed to stop it. This is very likely to create a memory leak.
2017-7-20 14:31:03 org.apache.coyote.AbstractProtocol start
信息: Starting ProtocolHandler ["http-bio-8080"]
2017-7-20 14:31:03 org.apache.coyote.AbstractProtocol start
信息: Starting ProtocolHandler ["ajp-bio-8009"]
2017-7-20 14:31:03 org.apache.catalina.startup.Catalina start
信息: Server startup in 15433 ms
2017-7-20 14:31:03 org.apache.catalina.loader.WebappClassLoader loadClass
信息: Illegal access: this web application instance has been stopped already. Could not load org.json.JSONObject. The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact.
java.lang.IllegalStateException
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1600)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)
at com.yzhelper.until.TwoWeiMa.getToken(TwoWeiMa.java:152)
at com.yzhelper.until.MyTask.run(MyTask.java:13)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)
Exception in thread "Timer-2" java.lang.NoClassDefFoundError: org/json/JSONObject
at com.yzhelper.until.TwoWeiMa.getToken(TwoWeiMa.java:152)
at com.yzhelper.until.MyTask.run(MyTask.java:13)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)
Caused by: java.lang.ClassNotFoundException: org.json.JSONObject
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)
... 4 more