Added in API level 21

android.system

Classes

Int64Ref A signed 64bit integer reference suitable for passing to lower-level system calls. 
Os Access to low-level system functionality. 
OsConstants Constants and helper functions for use with Os
StructCmsghdr Corresponds to C's struct cmsghdr
StructMsghdr Corresponds to C's struct msghdr 
StructPollfd Used as an in/out parameter to Os#poll
StructStat File information returned by Os#fstat, Os#lstat, and Os#stat
StructStatVfs File information returned by Os#fstatvfs and Os#statvfs
StructTimespec Corresponds to C's struct timespec from <time.h>
StructTimeval Corresponds to C's struct timeval from sys/time.h
StructUtsname Information returned by Os#uname
SystemCleaner Java.lang.ref.Cleaner encourages each library to create a Cleaner, with an associated thread, to process Cleaner Runnables for that library's registered cleaning actions. 
VmSocketAddress A virtio-vsock address VmSocketAddress

Exceptions

ErrnoException A checked exception thrown when Os methods fail.