1、问题

运行 spring boot 时报以下错误信息

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
     |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v1.2.2.RELEASE)


java.lang.UnsupportedClassVersionError: javax/annotation/ManagedBean : Unsupported major.minor version 51.0

检查Java版本 使用的是1.6

java version "1.6.0_43"
Java(TM) SE Runtime Environment (build 1.6.0_43-b01)
Java HotSpot(TM) 64-Bit Server VM (build 20.14-b01, mixed mode)

2、原因

报错的为 javax/annotation/ManagedBean 找到这个类所在jar

License Badge

打开里面的MANIFEST.MF文件

Manifest-Version: 1.0
Ant-Version: Apache Ant 1.9.3
Created-By: 1.7.0_67-b01 (Oracle Corporation)
Specification-Title: Apache Tomcat
Specification-Version: 8.0
Specification-Vendor: Apache Software Foundation
Implementation-Title: Apache Tomcat
Implementation-Version: 8.0.20
Implementation-Vendor: Apache Software Foundation
X-Compile-Source-JDK: 1.7
X-Compile-Target-JDK: 1.7

可以看出需要 jdk1.7的编译 参考JDK各版本对应的错误编码：

J2SE 8 = 52 
J2SE 7 = 51 
J2SE 6.0 = 50 
J2SE 5.0 = 49 
JDK 1.4 = 48 
JDK 1.3 = 47 
JDK 1.2 = 46 
JDK 1.1 = 45

3、解决

下载JDK7，将 1.6 换成 1.7 即可