如何实现Serializable？

Question

如何对Serializable接口执行implement操作？

我有一个class Student，需要能够将其保存到磁盘。对于我的家庭作业，我必须序列化五个不同的Student对象并将它们保存到文件中。

class Student {
     String mFirstName;
     String mSecondName;
     String mPhoneNumber;
     String mAddress;
     String mCity;

Student(final String pFirstName, final String pSecondName, final String pPhoneNumber, final String pAddress, final String pCity){
    this.mFirstName = pFirstName;
    this.mSecondName = pSecondName;
    this.mPhoneNumber = pPhoneNumber;
    this.mAddress = pAddress;
    this.mCity = pCity;

}}

我曾尝试使用ObjectOutputStream来序列化Student，但它抛出了一个错误：

ObjectOutputStream lOutputStream = new ObjectOutputStream(new FileOutputStream("file.txt", true));
lOutputStream.write(new Student("foo","bar","555-1234","Flat 40","Liverpool"));

Answer 1

你唯一需要做的就是实现Serializable。在实现此接口时，您唯一需要担心的是确保该类的所有字段也实现了Serializable接口。在本例中，所有字段都是String，并且它们已经实现了Serializable。因此，您只需要添加实现可序列化的。https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/io/Serializable.html

public class Student implements Serializable {
    String first;
    String second;
    String phone;
    String cityAddress;
    String cityStreet;

    public Student(String s1, String s2, String s3, String s4, String s5) {
        first = s1;
        second = s2;
        phone = s3;
        cityAddress = s4;
        cityStreet = s5;
    }
}