While trying to install the application downloaded from
github I get the following error:
[WARNING]
Error injecting: com.vaadin.integration.maven.UpdateThemeMojo
java.lang.TypeNotPresentException: Type com.vaadin.integration.maven.UpdateThemeMojo not present
at org.eclipse.sisu.space.URLClassSpace.loadClass(URLClassSpace.java:147)
...
Caused by: java.lang.UnsupportedClassVersionError: com/vaadin/integration/maven/UpdateThemeMojo : Unsupported major.mino
r version 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
How to rid it?
Another place you might want to check is the JAVA_HOME and JRE_HOME system properties - if you’re running from command line, those are the versions that will be used. Both should probably be pointed to a Java 8 JDK root folder (in Windows, something like C:\Program Files\Java\jdk1.8.0_xyz).
Also note that you will very likely want a JDK and not a JRE.
That’s usually caused by wrong Java version. Make sure the process definitely accesses that Java 8 installation instead of e.g. some older Java 7 installation. Note that it’s not enough that the project itself has Java 8, every run configuration has its own Java settings. If you are using Eclipse, there is a JRE tab in the run configurations where you can check and change the defaults.