???????????Serializable???

????ObjectOutputStream????Serializable????????????????л??????????￡?ObjectOutputStream????????????л??????????л???????????????transient????????????????л????????????л??????transient???????????????????л??????????

??????ObjectOutputStream??????????????л???????????????

????1???????????ж????????????б????????????????????????????????classpath?в?????????????????????????ClassNotFoundException??

????2????????л?????????????κι???????

???????????????????????л????????????????л????????????????writeObject()??readObject()??????

private void writeObject(java.io.ObjectOutputStream out) throws IOException
private void readObject(java.io.ObjectInputStream in) throws IOException?? ClassNotFoundException;

??????ObjectOutputStream?????Customer??????????л???????????????writeObject()???????????????????????????????????л??????????writeObjectt()?????У??????????ObjectOutputStream??defaultWriteObject()?????????????????????????????л???????????ó??????л?????????????????defaultReadObject()??????

??????Щ?????а????Щ??????????Щ???????????????????????????????????л??????????????л?????????????????????????????????????????????????????????????м?????????л?????????л???????????????????????????

???????????л?????????л???????????????????????????????????????????????????????????????????????????????????????б??

??????????????????Щ????????????transient???????????????????????л????????

???????????Externalizable???

????Externalizable???????Serializable?????????????????Externalizable??????????????????????????????л??????Externalizable???????????????????

public void writeExternal(ObjectOutput out) throws IOException
public void readExternal(ObjectInput in) throws IOException ?? ClassNotFoundException

?????????????л?????????????????л???????

????????????Externalizable????????????з????л???????????????????????????????????б??????????з?????????????????????????????????????ù??????????????????private??????protected?????????java.io.InvalidException: no valid constructor????

????????????л???????汾?????л???????

???????????Serializable?????????????????л??汾???????????????

private static final long serialVersionUID;

????????serialVersionUID??????Java?????????????????????????????????????????????????????????±?????????????????serialVersionUID?????п?????????仯??

???????serialVersionUID???????????????Java???????????????????????ò????Java???????????п?????2????serialVersionUID????п?????????????????serialVersionUID??????????????????????????????л?????????????serialVersionUID?????????????????????????serialVersionUID???????????

????1?????Щ??????????????汾?????л?????????????????????汾?????????serialVersionUID??

????2?????Щ????????????????汾?????л?????????????????????汾???в????serialVersionUID