Android Socket實現重用harmony項目
socket/serversocket.java --> socketImpl.java (java.net)
socketimpl.java --> java/net/plainsocketimpl.java --> Libcore Os IoBridge etc (libcore.io)
socketimpl.java --> java/nio/SocketChannelImpl.java --> Libcore Os IoBridge etc (libcore.io)
libcore OS --> libcore/io/Posix.java --> libcore_io_Posix.cpp --> linux posix api <sys/socket.h> (accept)
libcore IoBridge --> libcore/io/Posix.java --> libcore_io_Posix.cpp --> linux posix api <sys/socket.h> (sendto, recvfrom, etc)
Posix.java通過JNI (libcore_io_Posix.cpp)調用linux的posix API，例如accept, sendto, recvfrom等