JPA - 如何使 JSON POST 请求中不需要的字段

Question

我不想在 JSON POST 请求中传递价格字段，而是通过 setPrice() 自定义方法计算。

当我在 JSON POST 请求中传递我不想传递的价格字段时，无论值如何，它都可以正常工作，并且我的字段被正确计算并存储在 MySQL 表中。当我不通过它时，它只是出于某种原因返回并存储 0。

@Entity
public class User {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int user_id;

private String name;

@JsonFormat(pattern = "dd/MM/yyyy", timezone = "Europe/Berlin")
private Date date1;

@JsonFormat(pattern = "dd/MM/yyyy", timezone = "Europe/Berlin")
private Date date2;

private int beds;

private int meals;

private double price;


public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public int getUser_id() {
    return user_id;
}

public void setUser_id(int user_id) {
    this.user_id = user_id;
}

public double getPrice() {
    return price;
}


public void setPrice(double price) {

    this.price = (double) computePrice(date1, date2, beds, meals);
}

public int getBeds() {
    return beds;
}

public void setBeds(int beds) {
    this.beds = beds;
}

public Date getDate1() {
    return date1;
}

public void setDate1(Date date1) {
    this.date1 = date1;
}

public int getMeals() {
    return meals;
}

public void setMeals(int meals) {
    this.meals = meals;
}

public Date getDate2() {

    return date2;
}

public void setDate2(Date date2) {
    this.date2 = date2;
}


public long computePrice(Date date1, Date date2, int beds, int meals) {

    long duration = date2.getTime() - date1.getTime();

    long diffInDays = TimeUnit.MILLISECONDS.toDays(duration);

    if (diffInDays < 0) {
        return 0;
    }

    double priceBeds;
    double priceMeals = 700;

    if (beds == 1) {
        priceBeds = 2200;
    } else if (beds == 2) {
        priceBeds = 3300;
    } else if (beds == 3) {
        priceBeds = 4100;
    } else {
        priceBeds = 0;
    }

    if (meals < 0 || meals > 3) {
        meals = 0;
    }

    return (long) (diffInDays * (priceBeds + (meals * priceMeals)));

}

Answer 1

您正在为价格字段使用double 原语。 double 原语的默认值为 0，所以当不传递时，它被初始化为它。

如果你将使用Double 对象，则未传递时的默认值为空