There is no java code level migration guide for EAP 6.
For the most part, applications are easily migrative. Proceed with the migration using the https://access.redhat.com/documentation/en-US/JBoss_Enterprise_Application_Platform/6.4/html-single/Migration_Guide/index.html or https://access.redhat.com/documentation/en-US/JBoss_Enterprise_Application_Platform/6.4/pdf/Migration_Guide/JBoss_Enterprise_Application_Platform-6.4-Migration_Guide-en-US.pdf
For new features in JBoss EAP 6 refer https://access.redhat.com/documentation/en-US/JBoss_Enterprise_Application_Platform/6.4/html-single/6.4.0_Release_Notes/index.html
For previous version EAP 6 guide, refer Product Documentation of https://access.redhat.com/documentation/en/red-hat-jboss-enterprise-application-platform/
Hi Anup Dey, Thanks for your response but I need two or three improvements or general advantages of version 4.2.3 to 5 and 6. The release notes are more useful to the development department.
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