????????????????л???????л?
????1????Object?????????byte???У?????ж????????л?
????2?????л?????ObjectOutputStream???????????---writeObject????
?????????л?????ObjectInputStream????    ----readObject
????3?????л?????Serializable??
?????????????????л???????????????л?????????????
??????????????κη??????????????????????
???????????л??????????ζ??????????????????л????????????????????????
????????????????????а汾id???????????????????????????????????????   serialVersionUID
????4??transient?????
???????????????????JVM???????л????????????????????????л?
?????????д???????????????е????????б??????????????????????????????????
????????Щ????£????????????????????ArrayList????????з?????????????Ч??????л???
????5?????л??? ?????????????????????
????????????????л???????????????????????????л?
???????????????з????л????????????丸????????????????л?????????丸??????????????
???????????????????Щ?????
????1???????
????PrintStream  :???????
????PrintWriter  :????????
??????????Print()??????????????????????????????????
????2??????????????
????System???in??out???
????????????豸??????????豸???????
???????IO?????
????System.setIn(InputStream);
????//????????????????????????????д?????
????System.setOut(PrintStream);
????System.err(PrintStream);
????3?????????
??????Java???????????????????????????????Щ?????????????
??????OSExecute.command()???????command?????
????Process process = new ProcessBuilder(command.split(" ")).start();
????OSExecute.command("javap test");
????//javap??java??????????????
???????IO????????????????
?????????????try-catch-finally??Χ??????????????????????????????????printStackTrace()???????????finally?н???????????ж????ò???????????????????????????