Question

我正在尝试从文件中读取所有对象。下面是用于从文件中获取对象列表的方法的片段。

DELETE FROM
    YourTable
WHERE
    AID NOT IN ( SELECT
                    MAX(AID)
                 FROM
                    YourTable
                 GROUP BY
                    BID ,
                    AName ,
                    AType ,
                    APrice );

RegisterParty Class：

public List displayParties() {
        ObjectInputStream ois = null;
        List<RegisterParty> results = new ArrayList();
        try {
            FileInputStream fis = new FileInputStream("/media/user/disk2/myapp/assignment/party.ser");
            ois = new ObjectInputStream(fis);
            while (true) {
                System.out.println(" inside while true");
                results.add((RegisterParty) ois.readObject());
                System.out.println(results);
            }
        } catch (IOException ex) {
            ex.printStackTrace();
        }
        catch (Exception ex){
                ex.printStackTrace();

        } finally{
            try {
                ois.close();
            }catch (IOException ex){
                ex.printStackTrace();
            }
        }
        return results;
    }

但得到以下异常：

public class RegisterParty implements Serializable {
    String bookingPersonName;
    String childName;
    String childAge;
    String theme;
    String foodAlergies;
    String noOfGuest;
    String specialGuest;

    public String getBookingPersonName() {
        return bookingPersonName;
    }

    public void setBookingPersonName(String bookingPersonName) {
        this.bookingPersonName = bookingPersonName;
    }

    public String getChildName() {
        return childName;
    }

    public void setChildName(String childName) {
        this.childName = childName;
    }

    public String getChildAge() {
        return childAge;
    }

    public void setChildAge(String childAge) {
        this.childAge = childAge;
    }

    public String getTheme() {
        return theme;
    }

    public void setTheme(String theme) {
        this.theme = theme;
    }

    public String getFoodAlergies() {
        return foodAlergies;
    }

    public void setFoodAlergies(String foodAlergies) {
        this.foodAlergies = foodAlergies;
    }

    public String getNoOfGuest() {
        return noOfGuest;
    }

    public void setNoOfGuest(String noOfGuest) {
        this.noOfGuest = noOfGuest;
    }

    public String getSpecialGuest() {
        return specialGuest;
    }

    public void setSpecialGuest(String specialGuest) {
        this.specialGuest = specialGuest;
    }

    public String toString(){
        return bookingPersonName+" "+childName+" "
                +childAge+" "+foodAlergies+" "+theme+" "+noOfGuest+" "+specialGuest;
    }
}

RegisterParty实现了可序列化的接口。它是一个基于菜单的应用程序，所以当我将对象保存在文件中时，它的保存成功。但是调用方法来获取列表中的所有对象，它抛出异常。任何想法为什么？

此方法成功执行以序列化对象：

java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: models.RegisterParty
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1354)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:370)
    at helper.HelperFunctions.displayParties(HelperFunctions.java:39)
    at services.PartyOperations.listAllParties(PartyOperations.java:64)
    at assignment.App.main(App.java:34)
    at helper.HelperFunctions.saveParty(HelperFunctions.java:24)
    at services.PartyOperations.registerParty(PartyOperations.java:53)
    at assignment.App.main(App.java:28)
Caused by: java.io.NotSerializableException: models.RegisterParty
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1183)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347)
    at helper.HelperFunctions.saveParty(HelperFunctions.java:20)
    at services.PartyOperations.registerParty(PartyOperations.java:52)
    ... 1 more

Answer 1

当我实现Serializable对象时，我在类中添加了一个静态变量serialVersionUID：

.product {
  z-index:1000;
}

此行被eclipse或android studio添加为建议。我不知道如何使用IntelliJIdea。

值得一试！我相信这个ID用于反序列化。

写作流产; java.io.NotSerializableException

1 个答案: