B4J Question App has been compiled by a more recent version of the java runtime

[dieterp]

I'm running into incompatible version issues when I try run m B4J app (Built on my local laptop) on my Windows Server. The exact error is "App has been compiled by a more recent version of the java runtime <Class file version 53.0>, this version of the java runtime only recognizes class file versions up to 52.0"

I am using the latest version OpenJDK 14 from the B4x website on my local laptop. As I understand it version 52.0 = Java 8 and version 53.0 = Java 9. My questions are:

1) Why would my app compile in java 9 if I'm using a later version of Java
2) How can I go about getting the app to be compatible with the Java version running on my server

 

[EnriqueGonzalez]

only recognizes class file versions up to 52.0

it says, that recognizes UP to, not that your app was compiled with 52.

How can I go about getting the app to be compatible with the Java version running on my server

it seems you have java 8 in your server, if you compiled with java 14, install java 14 in your server.

 

[MicroDrie]

it says, that recognizes UP to, not that your app was compiled with 52.


it seems you have java 8 in your server, if you compiled with java 14, install java 14 in your server.

Or less impact than upgrading a server OS, install Java 1.8 for B4A and B4J in addition to the Java 14 SDK. In addition to Java SDK version 14.0.1 for my program development on laptop, I use at the same time version 1.8 for B4A running without any problems.

 

[EnriqueGonzalez]

Or less impact than upgrading a server OS,

I never mentioned upgrading sever OS.

install Java 1.8 for B4A and B4J in addition to the Java 14 SDK. In addition to Java SDK version 14.0.1 for my program development on laptop, I use at the same time version 1.8 for B4A running without any problems.

Latest b4j web server is not compatible with java 8 only java 11 onwards

 

[MicroDrie]

Compatibility has never been our strong suit as programmers