This is my Cart Entity class:
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@Entity
@Table(name = "carts")
public class Cart implements Serializable {
private static final long serialVersionUID = 3L;
public Cart() {
super();
}
@Id
private String username;
@ElementCollection
@CollectionTable(name="cartsbooks", joinColumns=@JoinColumn(name="username"))
@Column(name="quantity")
@MapKeyJoinColumn(name="isbn", referencedColumnName="isbn")
private Map<Book,Integer> articles;
private float bill;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public Map<Book,Integer> getArticles() {
return articles;
}
public void setArticles(Map<Book,Integer> articles) {
this.articles = articles;
}
public float getBill() {
return bill;
}
public void setBill(float bill) {
this.bill = bill;
}
}
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As you can see the getArticles() method returns a HashMap<Book, Integer>, so the subsequent call get(book) should return an Integer value.
Thank you!