To adhere to final field semantics Serialization should issue a "freeze action" after reconstituting objects that have values set on their final fields, see JLS 17.5 [1].

A number of years ago there was a proposal to use Unsafe.put*Volatile methods to set final fields during default deserialisation, JDK-6647361 [2][3], but it never made it due to concerns about the potential negative impact of the additional fences. Now we have a, private, fences API in the platform, I think it is time to revisit this.

Note:
    Section 17.5.3 in the JLS [3], “Freezes of a final field occur both
    at the end of the constructor in which the final field is set, and
    immediately after each modification of a final field via reflection
    or other special mechanism.” I believe this is a consequence of
    the way in which setting of final fields is supported in the public
    API, Field.setAccessible(), ( as defined by JSR 133 ) and should
    not restrict an implementation from using a more performant
    means, as is suggested here. The statement in the JLS should
    be revisited.

[1] http://docs.oracle.com/javase/specs/jls/se8/html/jls-17.html#jls-17.5
[2] https://bugs.openjdk.java.net/browse/JDK-6647361
[3] http://mail.openjdk.java.net/pipermail/core-libs-dev/2010-November/005292.html
     http://mail.openjdk.java.net/pipermail/core-libs-dev/2010-December/005456.html
[4] http://docs.oracle.com/javase/specs/jls/se8/html/jls-17.html#jls-17.5.3