用了@Component注解后提示JDK版本不对

J2EE开发环境，加了@component后，启动Tomcat报错：

2016-07-19 15:19:57  INFO [Thread-1] (LocalContainerEntityManagerFactoryBean.java:238) 
- Building JPA container EntityManagerFactory for persistence unit 'consumer'
2016-07-19 15:20:00 ERROR [Thread-1] (ContextLoader.java:312) - Context initialization failed
java.lang.UnsupportedClassVersionError: cn/jiguang/common/resp/APIConnectionException : 
Unsupported major.minor version 51.0 (unable to load class cn.jiguang.common.resp.APIConnectionException)
    at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2824)
    at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1150)
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1645)
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1523)
    at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
    at java.lang.Class.getDeclaredConstructors0(Native Method)
    at java.lang.Class.privateGetDeclaredConstructors(Class.java:2389)
    at java.lang.Class.getDeclaredConstructors(Class.java:1836)