导出可运行 jar 后出现 Java 异常

Question

当我尝试运行 jar 时，使用 eclipse 将其导出后，这就是我得到的:

Exception in thread "main" java.lang.UnsupportedClassVersionError: ietstesten : Unsupported major.minor version 52.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(Unknown Source)
    at java.security.SecureClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.access$100(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)

我真的不知道为什么会发生这种情况。我尝试将所有内容导入到新项目中，但似乎没有解决任何问题。

当我双击 jar 时，我收到“Java 异常发生”

Answer 1

This happens because of your jar file compiled in java 1.8 But you are running in the lower version than 1.8

1. 安装 Java 8
2. 在 IDE 中将合规性级别更改为 1.8

Java 版本历史记录

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