我不确定我是否正确描述了与JPA的一对多关系。 我有3张桌子: 杂工表包含姓名,地址,电话号码等。 公司表有:公司名称,地址,电话号码等。 WorkOrder表:workOrder编号,工作地点地址,FK到杂工的ID,FK到公司的ID。 添加新的工作订单时,我使用select从数据库中选择公司和杂工名称,然后填写工作订单表单。 问题是如何保存它?
Handyman.java
@OneToMany(cascade=CascadeType.ALL)
@JoinColumn(name="Handymans_list_id")
private Set<WorkOrder> workOrders;
public Set<WorkOrder> getWorkOrders() {
return workOrders;
}
public void setWorkOrders(Set<WorkOrder> workOrders) {
this.workOrders = workOrders;
}
Company.java
@OneToMany(cascade=CascadeType.ALL)
@JoinColumn(name="Companys_list_id")
private Set<WorkOrder> workOrders;
public Set<WorkOrder> getWorkOrders() {
return workOrders;
}
public void setWorkOrders(Set<WorkOrder> workOrders) {
this.workOrders = workOrders;
}
WorkOrder.java
@ManyToOne(optional=false)
@JoinColumn(name="Companys_list_id", referencedColumnName="id")
//@ManyToOne
//@JoinColumn(name = "Companys_list_id")
private Company company;
@ManyToOne(optional=false)
@JoinColumn(name="Handymans_list_id", referencedColumnName="id")
//@ManyToOne
//@JoinColumn(name = "Handymans_list_id")
private Handyman handyman;
WorkOrderDAOHibernate.java
public WorkOrder saveWorkOrder(WorkOrder workOrder)
{
System.out.println("Open session for saving work order ...");
SessionFactory sf = HibernateUtil.getSessionFactory();
Session session = sf.openSession();
Transaction trans = session.beginTransaction();
//Integer id = (Integer) session.save(workOrder);
//Company company = workOrder.getCompany();
//Handyman handyman = new Handyman();
//String name = handyman.getHandymanName();
//System.out.println("Printing company =" + company);
//System.out.println("Printing handyman = "+ handyman);
//System.out.println("Handymans name = " + name);
//
//workOrder.setCompany(company);
//workOrder.setHandyman(handyman);
System.out.println("Workorder "+workOrder);
Integer id = (Integer) session.save(workOrder);
trans.commit();
workOrder.setId(id);
session.close();
return workOrder;
}
workorder3.jsp
<s:form action="resultAction1" namespace="/">
<s:actionerror/>
<s:textfield name="workOrder.workOrder" label="Work order number" />
<s:textfield name="workOrder.address" label="Adress/Location" />
<s:textfield name="workOrder.email" label="Email" />
<s:textfield name="workOrder.comment" label="Comment" />
<s:textfield name="workOrder.dateReceived" label="Date receved" />
<s:textfield name="workOrder.price" label="Price" />
<h4>
<s:select label="Pick the company name "
headerKey="-1" headerValue="Select Company name"
list="companyList"
name="yourCompanyList"
/>
</h4>
<h4>
<s:select label="Pick handyman name "
headerKey="-1" headerValue="Select Handyman name"
list="handymanList"
name="yourHandymanList"
/>
</h4>
<s:submit value="submit" name="submit" />
答案 0 :(得分:3)
您正试图通过在HandyMan and Company中放置对WorkOrder的引用来定义双向关系。在双向实现中,只有一方是该关系的所有者。所有者方将具有@JoinColumn注释,而另一方将在@OneToMany中具有mappedBy属性,该属性引用映射@JoinColumn的bean属性。
所以你的类映射如下:
Handyman.java
@OneToMany(cascade=CascadeType.ALL,mappedBy="handyman")
private Set<WorkOrder> workOrders;
<强> Company.java 强>
@OneToMany(cascade=CascadeType.ALL,mappedBy="company")
private Set<WorkOrder> workOrders;
在 WorkOrder.java
中@ManyToOne(optional=false)
@JoinColumn(name="Companys_list_id", referencedColumnName="id")
private Company company;
@ManyToOne(optional=false)
@JoinColumn(name="Handymans_list_id", referencedColumnName="id")
private Handyman handyman;
保存时:
HandyMan handyMan = new HandyMan();
handyMan.setId() // Set the selected id.
Company company = new Company();
company.setId() // Set the selected company id.
workOrder.setCompany(company);
workOrder.setHandyMan(handyMan);
// Populate other details of work order and save using hibernate api.