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From Daniel John Debrunner <...@debrunners.com>
Subject Re: Single JDK14 compile model?
Date Sun, 06 Mar 2005 15:50:25 GMT
Andrew McIntyre wrote:

> - any classfile modified in this way probably should not be subclassed,
> to avoid possible problems compiling or verifying classes in past or
> future JVMs. This could be achieved in the source by clearly documenting
> classes to be modified this way, and in the binary by setting ACC_FINAL
> at the same time that we unset ACC_ABSTRACT.

No, we require the class files modified to be sub-classed (see my other
long e-mail from this morning) and there is no issue with it.

The JVM/verifier does not and must not check at runtime that a class
implements all the the required methods from its declared interfaces.
This would break the Java model of backwards compatibility, e.g. running
a simple JDBC 2.0 driver in JDK 1.4. There's even the
AbstractMethodError and NoSuchMethod errors to handle this case.

Dan.


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