Watch Out For OpenJDK Differences on Android N
Android N is shipping with its
derived from the OpenJDK, rather than from Apache Harmony. Many of
the Harmony classes were modified in Android since Android 1.0, and
the JDK itself has gone through a couple of major releases. So,
while there are large test batteries designed to confirm that everything
is compatible, some changes in behavior are likely to slip through
For example, eagle-eyed developers have noted that
java.io.File path normalization has changed
java.text.DecimalFormat has changed.
I have reproduced both of their test results and can confirm the
It is entirely possible that these will be altered to be compatible with past versions of Android before Android N ships in final form. It is theoretically possible that these are the only two such differences, but that seems unlikely.
Hence, more so than with past developer previews, it is key for you to be testing your code early and thoroughly, to see whether you trip over similar sorts of JDK class differences. At minimum, you will have time to find a workaround. Even better, file an issue, and see if the incompatibilities can get fixed.