WAS v8.0 > Migration and coexistence > Distributed operating systems > Overview
Migrate API and specifications
WAS began supporting JDK 6 in v8.0.
In general, existing v6.x application binaries that were developed using JDK 1.4 and 5 are highly compatible and typically do not require modifications to run. However, recompilation of the JDK 1.4 or 5 applications at the JDK 6 level might necessitate modifications of the source code to conform to incompatible changes that are present in JDK 6. As part of your migration planning, you should review the JDK compatibility restrictions that are documented by Sun Microsystems at Java SE 6 Release Notes: Compatibility.
A mixed cell containing v6.x and v7.0 nodes requires that all application binaries deployed on v6.x remain at the lowest JDK level associated with the v6.x nodes. Although you can successfully migrate v6.x applications to v8.0, this is only meant to be a temporary state as you transition to v8.0. After you begin migration to v8.0, plan to complete the migration of the entire cell, update your tooling to v8.0, and update the applications to conform to JDK 6 requirements. Complete this action before any further application changes. After we have completely migrated your cell to v8.0, upgrade the application binaries to the JDK 6 level the next time that you make application modifications that require recompiling. This action might require source code changes to the application to conform to the JDK 6 API changes as documented by Sun Microsystems.
The Java Virtual Machine Debug Interface (JVMDI) and the Java Virtual Machine Profiler Interface (JVMPI) were deprecated in JDK 5 and removed in JDK 6.
Read the Specifications and API documentation article in the information center for a summary of the specifications and API documentation supported in current and prior product releases.
For more information on the items deprecated in WASv8.0, read the Deprecated, stabilized, and removed features article in the information center. Migrate and coexisting application servers
Specifications and API documentation