Readobjectnodata in serialization

The readobjectnodata method was added in JDK. However, it has been mentioned in many books both at home and abroad, but it does not really involve examples.

Some students asked about its usage today to explain it.

Original Condition of readobjectnodata pojopublic class person implements serializable {private int age; Public Person () {}// setter getter ...} serialize person P = new person (); p. setage (10); objectoutputstream OOS = new objectoutputstream (New fileoutputstream ("C:/person. ser "); OOS. writeobject (p); OOS. flush (); OOS. close (); after the class structure changes, the serialized data remains unchanged. pojo animal implements serializable explicitly writes readobjectnodata public class animal implements serializable {private string name; Public animal () {} // setter getter... private void readobjectnodata () {This. name = "zhangsan" ;}} person extends animal public class person extends animal implements serializable {private int age; Public Person () {}// setter getter ...} deserialization objectinputstream OIS = new objectinputstream (New fileinputstream ("C:/person. ser "); person sp = (person) Ois. readobject (); system. out. println (sp. getname (); readobject calls readobjectnodata