Bi Xiangdong _java Basic Video tutorial 21st day _io Stream (1)

21st Day -01-io Stream (serialization of objects)

ObjectInputStream and ObjectOutputStream

• The object being manipulated needs to implement the Serializable interface (tag interface)
• Not required, but it is strongly recommended that all serializable classes be explicitly declared Serialversionuid

 PackageBxD;ImportJava.io.*; Public classObjectstreamdemo { Public Static voidReadobj ()throwsException {objectinputstream ois=NewObjectInputStream (NewFileInputStream ("Person.object")); Person Person=(person) ois.readobject ();        SYSTEM.OUT.PRINTLN (person);    Ois.close (); }     Public Static voidWriteobj ()throwsException {objectoutputstream oos=NewObjectOutputStream (NewFileOutputStream ("Person.object")); Oos.writeobject (NewPerson ("Lily", "the", "Us"));    Oos.close (); }     Public Static voidMain (string[] args)throwsException {//writeobj ();readobj (); }}/*The output is LILY:0:CN because age is not serialized (using the initial value of 0), and the static variable country is not serialized (using the initial value of CN).*/classPersonImplementsSerializable { Public Static Final LongSerialversionuid = 42L;//It is strongly recommended that all serializable classes be explicitly declared Serialversionuid    PrivateString name; transient intAge//If an instance variable does not need to be serialized, you can use the transient adornment    StaticString country = "cn";//the serialization behavior is only for the Java heap (heap), and static variables do not exist in the heap.Person (String name,intAge , String Country) {         This. Name =name;  This. Age =Age ;  This. Country =Country; }     PublicString toString () {returnName + ":" + Age + ":" +Country; }}

Bi Xiangdong _java Basic Video tutorial 21st day _io Stream (1)