这是我的 Java 环境:
~: java -version
java version "11.0.1" 2018-10-16 LTS
Java(TM) SE Runtime Environment 18.9 (build 11.0.1+13-LTS)
Java HotSpot(TM) 64-Bit Server VM 18.9 (build 11.0.1+13-LTS, mixed mode)
但是在编译后尝试执行程序时,出现以下错误:
Error: LinkageError occurred while loading main class ClassName
java.lang.UnsupportedClassVersionError: ClassName 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 54.0
我的 PATH 和 JAVA_HOME 变量都指向这个版本的 java。我下载了其他版本,但似乎没有在系统中注册:
update-alternatives --display java
java - auto mode
link best version is /usr/lib/jvm/java-11-openjdk-amd64/bin/java
link currently points to /usr/lib/jvm/java-11-openjdk-amd64/bin/java
link java is /usr/bin/java
slave java.1.gz is /usr/share/man/man1/java.1.gz
/usr/lib/jvm/java-11-openjdk-amd64/bin/java - priority 1101
slave java.1.gz: /usr/lib/jvm/java-11-openjdk-amd64/man/man1/java.1.gz
那么编译和执行是怎么用不同的版本来完成的呢?