“Caused by: java.lang.UnsupportedClassVersionError: unsupported classversion 51.0”

Error:

“Caused by: java.lang.UnsupportedClassVersionError: unsupported classversion 51.0”

Replication Of Issue: 

When we try to deploy any service which has been developed/Migrated on JDK which is higher than the JDK version used by the server

Error Stack:

[04:04:30 PM] [Deployer:149193]Operation 'deploy' on application 'ServiceName' has failed on 'Server1'
[04:04:30 PM] [Deployer:149034]An exception occurred for task [Deployer:149026]deploy application 'ServiceName' on Server1.: Failed to load webapp: ''ServiceName'.war'.
[04:04:30 PM] Weblogic Server Exception: weblogic.application.ModuleException: Failed to load webapp: ''ServiceName'.war'
[04:04:30 PM] Caused by: java.lang.UnsupportedClassVersionError: <Package Name> : unsupported classversion 51.0
[04:04:30 PM]   See server logs or server console for more details.
[04:04:30 PM] weblogic.application.ModuleException: Failed to load webapp: ''ServiceName'.war'
[04:04:30 PM] ####  Deployment incomplete.  ####
[04:04:30 PM] Remote deployment failed (oracle.jdevimpl.deploy.common.Jsr88RemoteDeployer)

Resolution:

  

1)      1) Check the JDK Requirement of the JDeveloper version which is to be installed. Eg. As per Oracle documentation for Jdev 11.1.1.6.0 the JDK shall be JDK_6.0_27 or above.

2)       2) Check the server jdk version.To do the same t go to location WL_HOME/common/bin/commEnv.cmd ad Look for lines like the ones below (examples are from a WLS install on a Unix machine)

#JAVA_USE_64BIT, true if JVM uses 64 bit operations.

3)      3) Install JDK version which is either server version or lower than that version and then build/migrate your service.

  

Reference: To find the JDK version of your server click here.