Do the Android Dalvik standard libraries have any class similar to the undocumented class sun.misc.Unsafe in Java SE which allows direct access to memory.
Android implements parts of sun.misc.Unsafe, primarily to support the JSR-166 concurrency classes. It’s not part of the Android API.
It has the JNI bridge which could allow for just about anything but it’s not “unsafe” since you have to code that into your app. As far as I know there is no exposed way to get out of the JVM sandbox (at least not without finding an exploit).