一、问题描述

在本地打包后，在服务器上运行Jar包，出现：

Exception in thread "main" java.lang.UnsupportedClassVersionError: XXX has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0

二、解决方法

切换jdk8版本切换到jdk11版本，再次运行即可。

三、原理说明

1、解读错误

使用更新版本的JRE进行编译，但现在尝试使用更旧版本的JRE进行运行。

2、Java版本号一览 

45 = Java 1.1

46 = Java 1.2

47 = Java 1.3

48 = Java 1.4

49 = Java 5

50 = Java 6

51 = Java 7

52 = Java 8

53 = Java 9

54 = Java 10

55 = Java 11

56 = Java 12

57 = Java 13

58 = Java 14

59 = Java 15

60 = Java 16

61 = Java 17

62 = Java 18

63 = Java 19

64 = Java 20

65 = Java 21

66 = Java 22

 四、参考

How to Fix java.lang.UnsupportedClassVersionError | Baeldung