Unsupported major.minor version 51.0 when deploying solr 4.7.2

[Danesh Kuruppu <dk...@gmail.com>]

Hi all,

I am getting following error when I try to deploy solr.war.

java.lang.UnsupportedClassVersionError:
org/apache/solr/servlet/SolrDispatchFilter : Unsupported major.minor
version 51.0 (unable to load class
org.apache.solr.servlet.SolrDispatchFilter).

Server Java Version: 1.6.0_45
Solr Version: solr-4.7.2

I found that above error occurs because solr is looking for java 7 runtime.
solr-4.7.2 suppose to be run at java 6.

What would be the cause for this error?

Thanks
Danesh

Re: Unsupported major.minor version 51.0 when deploying solr 4.7.2

[Shawn Heisey <ap...@elyograg.org>]

On 11/10/2014 5:43 AM, Danesh Kuruppu wrote:
> I am getting following error when I try to deploy solr.war.
> 
> java.lang.UnsupportedClassVersionError:
> org/apache/solr/servlet/SolrDispatchFilter : Unsupported major.minor
> version 51.0 (unable to load class
> org.apache.solr.servlet.SolrDispatchFilter).
> 
> Server Java Version: 1.6.0_45
> Solr Version: solr-4.7.2
> 
> I found that above error occurs because solr is looking for java 7 runtime.
> solr-4.7.2 suppose to be run at java 6.
> 
> What would be the cause for this error?

Solr 4.7.2 does require only Java 6.  I believe the binary version
available for download was also *compiled* using Java 6.  If you're
getting that error, then I think your Solr version must be newer than 4.7.2.

I checked out the 4.7.2 source using the following command:

svn co https://svn.apache.org/repos/asf/lucene/dev/tags/lucene_solr_4_7_2

Then I built the solr example (using the default JDK7 on my Linux
system), changed to the example directory, and ran:

/usr/lib/jvm/java-6-oracle/bin/java -jar start.jar

It started up just fine.  Remember -- I built the entire source code
using Java 7, and it ran fine on Java 6, because the build system
*tells* it to build binaries compatible with Java 6.

I think that somehow you have a newer Solr version than you think you do.

Thanks,
Shawn