ElementCollection使用PlayFrameWork

Question

我有一些相關的類。一個是有另一個類的對象集。像這樣，

@Entity 
public class Serving extends Model{ 

@Required 
public Item item; 
@Required 
public Float amount; 
@Required 
public Date time; 

public Serving(Item item, Float amount) { 
    super(); 
    this.item = item; 
    this.amount = amount; 
    this.time = new Date(); 
} 
} 

@Entity 
public class Receipt extends Model{ 

@Required 
@ElementCollection 
@NotNull 
public Set<Serving> servings; 
@Required 
DiningTable dtable; 

public Receipt(Set<Serving> servings, DiningTable dtable) { 
    super(); 
    this.servings = servings; 
    this.dtable = dtable; 
} 

//order'ın totalın hesaplamak lazım. 

} 

並且我也有一些yaml數據來初始化這個。

Serving(ser1): item : it1 amount : 1 time : 2012-04-05 12:10

Serving(ser2): item : it2 amount : 0.5 time : 2012-04-05 12:11

Serving(ser3): item : it3 amount : 2 time : 2012-04-04 13:10

Serving(ser4): item : it4 amount : 1 time : 2012-04-04 13:10

Serving(ser5): item : it5 amount : 0.5 time : 2012-04-04 14:00

Serving(ser6): item : it6 amount : 1 time : 2012-04-04 14:10

Serving(ser7): item : it7 amount : 1 time : 2012-04-03 16:00

Serving(ser8): item : it8 amount : 2 time : 2012-04-03 16:01

Serving(ser9): item : it9 amount : 1 time : 2012-04-03 16:30

Serving(ser10): item : it2 amount : 1 time : 2012-04-02 17:00

Receipt(rec1): dtable : tab1 servings :
- ser1 - ser2 - ser3

Receipt(rec2): dtable : tab2 servings : - ser4 - ser5

Receipt(rec3): dtable : tab3 servings : - ser6

Receipt(rec4): dtable : tab4 servings : - ser7 - ser8

Receipt(5): dtable : tab4 servings : - ser9 - ser10

，當我試圖初始化此數據它給這個錯誤，

14:13:01,200 WARN ~ SQL Error: 1364, SQLState: HY000 14:13:01,200 ERROR ~ Field 'servings_time' doesn't have a default value 14:13:01,200 ERROR ~ Could not synchronize database state with session org.hibernate.exception.GenericJDBCException: Could not execute JDBC batch update

我怎樣才能解決這個問題呢？

Answer 1

在服務類的構造函數必須獲得日期作爲參數。

public Serving(Item item, Float amount, Date date) { 
super(); 
this.item = item; 
this.amount = amount; 
this.time = date; 
} 

所以我要加入這個構造太...

Answer 2

你應該和你的註釋時間：

@Temporal(TemporalType.TIME) 
    public Date date; 

or 

    @Temporal(TemporalType.DATETIME) 
    public Date date;